COVID doi: 10.3390/covid6100174

Authors: John Musachia

Post-acute sequelae from SARS-CoV-2, or Long COVID, have evolved as SARS-CoV-2 has evolved into the Omicron subvariants, which have been the predominant and endemic circulating variants of SARS-CoV-2 since early 2022. Omicron is distinct from previous subvariants, with genetic mutations and biological characteristics that present and spread the virus differently, manifesting with upper rather than lower respiratory tract symptomology. Omicron COVID-19 expresses substantially decreased morbidity and mortality, but with higher transmissibility, resulting in Omicron’s endemicity. Unsurprisingly, Long COVID associated with Omicron recovery also presents differently, with dramatically reduced incidence and severity. These factors in turn have paralleled the closing of Long COVID care clinics, which has implications for Long COVID research.

COVID doi: 10.3390/covid6100173

Authors: Marco Floridia Liliana Elena Weimer Patrizia Rovere Querini Maria Bernadette Cilona Donato Lacedonia Terence Campanino Emanuela Barisione Teresita Aloe Guido Vagheggini Sara Grignolo Matteo Tosato Graziano Onder

The present national observational cohort study investigated in patients followed for long COVID—mostly hospitalized during acute infection—the presence, severity and evolution of dyspnea and its functional correlates. Dyspnea was assessed with the modified Medical Research Council (mMRC) dyspnea scale and its functional correlates via six-minutes walking distance (6MWD). A total of 217 individuals were evaluated. The mean difference in 6MWD between patients with and without dyspnea (mMRC score ≥ 1) was 87 m (95%CI 56–117, p < 0.001). Significant declines were observed between four and eight months from COVID-19 in prevalence of dyspnea (from 56.7% to 36.4%, p < 0.001), mean mMRC score (from 0.95 to 0.63, p < 0.001), and proportion of patients with 6MWD ˂ 65% of predicted value (from 15.5% to 9.4%, p = 0.035). Each additional point in mMRC score corresponded to −56.3 m walked at first assessment and to −47.7 m walked at second assessment. In the longitudinal analysis, each unitary mMRC score increase between the two assessments corresponded to a concurrent 6MWD reduction of 22.5 m (95%CI −40.1 to −4.8 m, p = 0.013). Although the prevalence of dyspnea reduced significantly over time, roughly one-third of patients remained affected eight months after COVID-19. The 6MWD was a sensitive measure in capturing the functional correlates of presence, severity and evolution of dyspnea.

COVID doi: 10.3390/covid6100172

Authors: Norifumi Kudeken

Long COVID has become a public health challenge, particularly in aging societies. Although persistent symptoms have been extensively investigated in the general adult population, their clinical significance in older adults differs because biological aging, frailty, multimorbidity, sarcopenia, and nutritional impairment modify both symptom expression and recovery. We conducted a structured narrative review of literature published from January 2020 through 7 September 2026, using database-specific searches conducted between 23 July and 7 September 2026. PubMed/MEDLINE was supplemented by Google Scholar, Cochrane Library, ScienceDirect, and manual reference-list searching, with particular attention to longitudinal and population-based studies involving older adults. Direct evidence from older-adult cohorts was distinguished from evidence extrapolated from broader adult studies. The available geriatric evidence indicates heterogeneous post-COVID trajectories, including persistent symptoms, mobility loss, worsening frailty, nutritional deterioration, cognitive concerns, and increased care dependency. We propose a hypothesis-generating, conceptual and pragmatic geriatric framework that integrates biological aging, frailty, nutrition, cognition, functional status, and long-term care into assessment and management. This framework is intended to complement, not replace, WHO/CDC symptom-based definitions and is not a validated Long COVID-specific clinical model.

COVID doi: 10.3390/covid6100171

Authors: Federica Giuzio Fabiano Svolacchia Lorenzo Svolacchia Carmela Saturnino Alessia Catalano Domenico Nicola Massariello Pierpaolo Di Lascio Giuseppe Guarro Giusy Carmen Imbriani Michele Di Marino

Background: The COVID-19 pandemic disrupted dermatologic and oncologic pathways in Italy and raised concern about delayed melanoma diagnosis. This systematic review evaluated whether pandemic-period healthcare disruption was associated with changes in melanoma presentation at diagnosis, focusing on Breslow thickness, stage-related clinicopathologic features, and diagnostic volume. Methods: Reporting was aligned with PRISMA 2020. The archived review record indicates searches of PubMed/MEDLINE, Scopus, Web of Science, Embase, and the Cochrane Library. Five verifiable primary Italian studies were retained for the principal synthesis after reconciliation of the original candidate set with the corrected eligibility criteria. Because study design, setting, comparator periods, and outcome reporting were heterogeneous, findings were synthesized narratively. Results: Across the five primary studies, melanoma diagnostic activity generally decreased during pandemic periods. Some cohorts reported thicker tumors or less favorable pathological features, whereas others found no significant difference in Breslow thickness, demonstrating substantial heterogeneity. Conclusions: The available observational evidence supports an association between pandemic-related healthcare disruption and changes in melanoma diagnostic activity and presentation in Italy, but it does not establish that delayed follow-up caused an increase in the population incidence of advanced melanoma. The exact final date of the original search and the original reviewer workflow could not be reconstructed from the archived review records and are reported as methodological limitations.

COVID doi: 10.3390/covid6100170

Authors: Yasemin Ardicoglu Akisin Rohat Sakar Ebrar Gultekin Parisa Sharafi Julide Sedef Gocmen

Background: Institutional COVID-19 testing patterns may differ from population-level trends owing to differences in testing practices, case ascertainment, and demographic composition. Retrospective evaluation of these patterns may provide insights into future surveillance of infectious diseases. This study aimed to characterise the demographic and temporal patterns of COVID-19 at TOBB University of Economics and Technology Faculty of Medicine Hospital and to contextualise these patterns within contemporaneous surveillance data from Turkey, the WHO European Region, and globally. Methods: In this retrospective descriptive study, SARS-CoV-2 reverse transcription polymerase chain reaction records from the hospital and aggregate World Health Organization surveillance data were evaluated from September 2020 to November 2022. Hospital data were evaluated according to age, sex, test positivity, and calendar month. Test positivity rates with 95% confidence intervals (CIs) were calculated, and sex-specific positivity rates were compared using Pearson’s chi-square test. Monthly hospital values were compared with the corresponding monthly national values for Turkey using Spearman’s rank correlation. Results: Among 49,318 SARS-CoV-2 reverse transcription polymerase chain reaction test results taken from the hospital data, 4810 were positive (9.75%; 95% CI: 9.49–10.01%). Test positivity did not differ between females and males (9.86% vs. 9.65%, p = 0.43). Adults aged 30–39 years represented the largest proportion of reported cases in the hospital (27.03%), Turkey (20.28%), the WHO European Region (16.48%), and globally (18.11%), whereas hospital testing was concentrated among adults aged 20–59 years. Hospital case counts peaked in November 2020 and February 2022, with the latter coinciding with the major COVID-19 surge in early 2022 in broader surveillance data. Monthly hospital case counts were positively correlated with monthly national case counts for Turkey (Spearman rho = 0.55, p = 0.003). Conclusions: Hospital-based surveillance identified major demographic and temporal features of the pandemic. However, differences in testing populations, case ascertainment, and reporting practices limit direct comparisons. Integrating institutional- and population-level data may strengthen surveillance frameworks for future respiratory infectious disease outbreaks.

COVID doi: 10.3390/covid6100169

Authors: Mércia Thaisa Araújo Costa Homero Elaine dos Santos Farias Fernanda de Souza Silva Domenico Lopes Sarah Alves de Assis Iasmim Isaires Neri dos Santos Igor Santana de Melo Fernanda Maria Araujo de Souza Olagide Wagner de Castro

Coronavirus disease 2019 (COVID-19) has been associated with sexual and reproductive disturbances, but whether these findings reflect transient systemic illness or persistent dysfunction remains uncertain. We systematically searched PubMed, Scopus, Web of Science, Virtual Health Library, World Health Organization Global Index Medicus, and Embase for human studies published from 2020 through 2025, supplemented by ResearchRabbit citation- and similarity-based screening; the final update was performed in June 2026. Eligible studies assessed sexual, reproductive, psychological/behavioral, or biological outcomes in individuals with acute or post-COVID-19 conditions. Three reviewers independently extracted and verified data, using design-specific National Institutes of Health, Joanna Briggs Institute, and Mendelian-randomization-specific frameworks to assess risk of bias. Because of substantial clinical and methodological heterogeneity, results were synthesized narratively. The final synthesis included 218 eligible reports, corresponding to 214 conservative study/cohort units after confirmed companion/derived-publication linkage. Erectile dysfunction was the most consistent sexual outcome, whereas reproductive studies mainly reported reduced semen quality and alterations in testosterone and gonadal-axis markers, often appearing short-term. Inflammatory, oxidative, endocrine, vascular, histopathological, molecular, and psychosocial findings supported a multidimensional framework. However, the evidence was predominantly male-focused, observational, and heterogeneous, limiting causal and long-term inference. COVID-19 may affect sexual and reproductive health through interacting biological and psychosocial pathways, but persistent infertility or definitive reproductive impairment remains unconfirmed. The protocol was not registered; no specific external funding was received.

COVID doi: 10.3390/covid6100168

Authors: Lenuța Silvia Nicoruț Timea Claudia Ghitea Rareș Cristian Daina Mădălina Diana Fehér László Fehér Lucia Georgeta Daina

Background: The COVID-19 pandemic exposed substantial differences in the capacity of local public health authorities to adapt, coordinate, communicate, engage communities, and sustain essential public health functions. Methods: We conducted a secondary, institution-level cross-sectional analysis of the verified analytic dataset for 20 Romanian Public Health Directorates (PHDs), representing 20 of 42 county-level territorial units. The file contained structural variables, eight binary COVID-19 response indicators, four normalized components, and an equal-weight composite capacity–response index, but no repeated annual observations, five-domain resilience scores, source-document matrix, or coder-reliability records. Comparisons between counties with university medical centers (CU; n = 10) and counties without them (FU; n = 10) used Mann–Whitney U and Fisher’s exact tests with Holm correction. Results: CU institutions served larger populations and had more employees, larger total budgets, higher budget per capita, more previous-crisis experience, more documented COVID-19 measures, and a higher exploratory composite index. Staffing density did not differ significantly. Vaccination-center involvement and communication/education were more frequently documented in CU institutions after multiplicity correction. Bucharest, Iași, and Cluj illustrate meaningful within-group variation despite a shared university-center context. Conclusions: The available data support descriptive evidence of institutional disparities associated with university-center context, but do not support causal claims, a longitudinal five-domain resilience model, or conclusions about digital maturity. The findings point to practical priorities for PHD–university medical-center collaboration, bidirectional community engagement, systematic after-action review, transparent national data collection, and future instrument validation.

COVID doi: 10.3390/covid6090167

Authors: Motoyuki Horii Norikazu Hishikawa Maki Asada Hitomi Oishi Koshiro Sawada

Objectives: To compare functional recovery during inpatient rehabilitation, assessed by Functional Independence Measure (FIM) gain and FIM efficiency, between the pre-pandemic and COVID-19 pandemic periods in older adults after hip fracture. Methods: This retrospective observational study included patients aged ≥65 years who underwent hip fracture surgery between January 2016 and December 2022 and were admitted to a convalescent rehabilitation ward. Patients were categorized into the pre-pandemic (2016–2019) and pandemic (2020–2022) periods. Functional outcomes included total, motor, and cognitive FIM gain and FIM efficiency. Multiple linear regression analyses were performed to identify factors associated with rehabilitation outcomes. Results: A total of 650 patients were analyzed. Admission motor and total FIM scores were significantly lower during the pandemic, whereas cognitive FIM scores were similar between groups. After multivariable adjustment, total FIM gain and total FIM efficiency did not differ significantly between periods. Exploratory analyses showed no significant associations between the pandemic period and motor or cognitive FIM gain or efficiency. Conclusions: Although motor and total FIM scores at admission were lower during the pandemic period, no statistically significant differences in adjusted total FIM gain or total FIM efficiency were observed between the pre-pandemic and pandemic periods.

COVID doi: 10.3390/covid6090166

Authors: Victoria L. McPherson Zella Berill Apryl Susi Cade M. Nylund Michael Rajnik Matthew D. Eberly

To identify whether a relationship exists between COVID-19 and appendicitis and compare the incidence of appendicitis during three pandemic years to the year prior to the pandemic, we conducted two observational retrospective studies: a propensity score-matched (PSM) cohort and a repeated monthly cross-sectional study. We used data from the Military Health System (MHS) Data Repository, which contains data about healthcare provided to active-duty service members, retirees, and their dependents. For the PSM cohort of 753,138 individuals, patients with COVID-19 between July 2020 and June 2021 from the MHS were matched to two similar people without COVID-19. Survival analysis using a conditional Cox proportional hazards model explored these relationships. For the cross-sectional study we used a separate, unmatched MHS cohort of 10,402,021 individuals. Poisson regression generated incident rate ratios (IRRs) of any appendicitis or complicated appendicitis by year, comparing three pandemic years to one pre-pandemic year. COVID-19 was associated with appendicitis or appendectomy within the first year of infection (hazard ratio: 1.13, 95% confidence interval: 1.02–1.26). The IRRs for both any appendicitis and complicated appendicitis were significantly less than one when comparing individual pandemic years to the pre-pandemic year. COVID-19 is associated with appendicitis. Rates of any appendicitis and complicated appendicitis were lower in each individual pandemic year.

COVID doi: 10.3390/covid6090165

Authors: Yvonne Groen Remon R. Nicolai Norbert A. Börger Saleh M. H. Mohamed Miguel Garcia Pimenta Geraldina F. Gaastra Anselm B. M. Fuermaier

This study measured the severity and frequency of self-reported symptoms of Attention Deficit Hyperactivity Disorder (ADHD) in Psychology students in a Dutch university before and during the COVID-19 pandemic, providing insights into how this population navigated the challenges of emerging adulthood amidst a global crisis. In total, 1446 first-year Psychology students in a Dutch university were recruited in four cohorts: 2018 (n = 404), 2019 (n = 277), 2020 (n = 350), and 2021 (n = 415). The cohorts in 2020 and 2021 were recruited during the COVID-19 pandemic. Responses on the Conners’ Adult ADHD Rating Scale (CAARS) Long Form were collected. For each cohort, scale scores were calculated, as well as frequencies of students screening positive for elevated ADHD symptoms. The proportion of participants screening positive for elevated ADHD symptoms was 21%, which did not significantly differ between cohorts (p = 0.076) and gender (p = 0.206). Subscale scores were indicative of a small increase in inattention symptoms with increasing duration of the pandemic from cohort 2018 to 2021. Small gender differences were found on the subscales. Roughly one in five first-year Psychology students in university screens positive for elevated ADHD symptoms. This pattern is stable across men and women and across four cohorts of students before and during the COVID-19 pandemic. Inattention symptoms slightly increased with increasing duration of the pandemic in cohort 2021.

COVID doi: 10.3390/covid6090164

Authors: Gabriel Vinícius Rolim Silva Letícia Maria Azevedo Martins Maria Karolaynne da Silva Bakul Akter Shopnil Akash Edilson Dantas da Silva Junior Katyanna Sales Bezerra Umberto Laino Fulco Jonas Ivan Nobre Oliveira

Ensitrelvir and nirmatrelvir are the two most widely used oral SARS-CoV-2 main protease inhibitors, yet their toxicological profiles have never been compared under a single computational panel. An identical panel of 105 toxicity endpoints per compound was generated with ADMETlab 3.0, ProTox 3.0, Deep-PK, admetSAR 3.0 and Pred-hERG 5.0, yielding 210 endpoint-level predictions across 17 toxicological domains. Each endpoint formed a matched pair classified as shared positive, shared negative, discriminant or crossed, and predictions were compared against primary clinical and nonclinical literature under a three-level admissibility hierarchy that excluded prescribing information, regulatory review documents and commercial databases. Of 93 class-assignable pairs, 73 assigned both to the same class, 62 negative, and 20 differed. Four domains were shared positive: genotoxicity, with broad genotoxicity and micronucleus probabilities of 1.000 for both molecules, respiratory toxicity, nephrotoxicity and neurotoxicity; ototoxicity was high for both in a single tool. The largest separation was hepatic: ensitrelvir returned drug-induced liver injury 1.000 and human hepatotoxicity 0.994, against 0.314 and 0.456 for nirmatrelvir. Target class therefore does not determine predicted toxicological profile. Genotoxicity, respiratory, renal and neural endpoints are class-level validation priorities, whereas hepatic and hERG endpoints require compound-specific testing. These findings are hypothesis-generating prioritization markers, not confirmed toxicity.

COVID doi: 10.3390/covid6090163

Authors: Furkan Bölen Ayşe Paralı Ak Merve Kapçık Mehmet Ağırbaşlı

Coronavirus disease 2019 (COVID-19) causes systemic inflammation and multi-organ injury that may persist beyond the acute illness. The Fibrosis-4 (FIB-4) index and the aspartate aminotransferase-to-platelet ratio index (APRI) are inexpensive liver fibrosis scores whose long-term prognostic value after COVID-19 pneumonia is undefined. In this single-center retrospective study, 101 adults hospitalized with severe COVID-19 pneumonia were followed for three years. FIB-4, APRI, and the chest computed tomography (CT) severity score were derived from admission data. Discrimination was quantified by the area under the receiver operating characteristic curve (AUC) and compared with the DeLong test; nested logistic regression models tested whether FIB-4 added prognostic information beyond age. Fifty-seven patients (56.4%) died, 39 in hospital and 18 after discharge. Admission FIB-4 was higher in non-survivors (median 3.0 vs. 1.5; p < 0.001), whereas APRI did not differ. FIB-4 showed superior prognostic accuracy for mortality compared to APRI (AUC 0.746 vs. 0.595; p = 0.002) and CT severity score (AUC 0.490; p = 0.001), while performing comparably to age alone (AUC 0.756; p = 0.870). Log-FIB-4 remained associated with mortality after adjustment for age (odds ratio 2.04, 95% CI 1.10–3.76) but not after further adjustment for C-reactive protein and creatinine (odds ratio 1.75, 0.86–3.55), whereas FIB-4 > 2.44 retained an age-adjusted odds ratio of 5.90 (2.20–15.83). Among patients discharged alive, FIB-4 was not associated with subsequent death. Admission FIB-4 was independently associated with three-year mortality and outperformed APRI and the CT severity score, but its prognostic information largely overlapped with age; it should be regarded as a composite admission risk index whose added value requires external validation.

COVID doi: 10.3390/covid6090162

Authors: Karen Webster-Kerr Andriene Grant Ardene Harris Romae Thorpe Daidre Rowe Deborah Henningham Tanielle Mullings Jovan Wiggan Carol Lord Tonia Dawkins-Beharie Jemma Azille Nicole Martin-Chen Eon Campbell Marsha Brown Jacqueline Duncan

Globally, the COVID-19 pandemic caused significant healthcare, economic and social impacts. This study described characteristics of COVID-19 mortality and determined risk of COVID-19 death by wave period in Jamaica. A cross-sectional analysis was conducted using data on confirmed COVID-19 cases reported to the National Surveillance Unit from 5 August 2020 to 4 October 2022. Multivariate logistic regression was used to determine odds of death by wave period, adjusting for age, sex and health region. 148,262 cases and 3654 COVID-19 deaths were included in the analysis. Increased odds of COVID-19 death were associated with male sex, age, and health region. Odds of death increased among males (OR:1.4, 95%CI: 1.3–1.5), residents in the Western health region (OR:1.4, 95%CI: 1.3–1.5) and persons ≥ 40 years (OR:18.2, 95%CI: 15.8–20.9). In comparison to Wave 4, odds of death were OR:3.4 (95%CI: 3.0–3.8) for Wave 3 and OR:2.6 (95%CI: 2.2–3.0) for Wave 1. Higher risk of death among males and older persons were observed across wave periods. Odds of death was greatest during Wave 3. This reinforces the need for responsive and adaptive health systems, as well as social and clinical interventions among high-risk groups.

COVID doi: 10.3390/covid6090161

Authors: Karthik Sivaraman Shubhra Dhawan Aditi Chopra Subraya Giliyar Bhat

Isolation, quarantine, and contact tracing are some of the most critical and commonly employed non-pharmaceutical interventions used to control the spread of COVID-19. However, the effectiveness of these strategies and their implementation depends on many factors, including a country’s population, the availability of resources to diagnose and effectively isolate infected individuals, culture and societal beliefs, family dynamics, and the feasibility and acceptability of isolation and quarantine policies among the public. This narrative review aims to appraise the evidence on the implementation strategies and shortcomings of isolation and quarantine strategies adopted during the COVID-19 pandemic. Previous evidence has found that early quarantine and isolation of COVID-19 patients were more effective than late adoption (5-fold vs. 2.6-fold). Approximately 90% of outbreaks could have been managed if 80% of contacts were monitored, traced, and isolated within four days of the index case being identified. For each new case of COVID-19, around thirty-six individuals should be traced. When the percentage of asymptomatic individuals is greater than 30%, isolation and contact tracing alone cannot contain the infection. The delay between symptom onset and isolation was the most important factor in determining infection control. Symptom-based isolation strategies should not be considered the sole criterion for isolation, as many asymptomatic individuals escaped isolation and increased the risk of disease transmission. Digital contact tracing, telemedicine, and artificial intelligence (AI)-based surveillance systems are potential adjuncts to support isolation and quarantine measures. Changes in societal behaviors and cultural norms, fear of stigma, psychological issues, economic burden, poverty, poor literacy rates, lack of public trust in government, and language were identified as challenges and barriers associated with the effective implementation of isolation and quarantine measures during the COVID-19 pandemic.

COVID doi: 10.3390/covid6090160

Authors: David Tross

This paper focuses on the wellbeing of a sample of older and predominantly middle-class UK individuals drawn from the Mass Observation Project (MOP) participant panel in 2020, covering the first months of the global COVID-19 pandemic and first UK national lockdown. It finds that socio-economic circumstances to some extent cushioned individuals against negative impacts of the pandemic but given the range of experiences within the sample, individual wellbeing cannot be explained by socio-economic position alone. Wellbeing emerged through a complex interaction of attitudes, activities, resources and circumstances, highlighting the dynamic interplay of agency and social structures that helps to understand more general features of living well. The findings also highlight that self-evaluated happiness depends partly on what individuals consider happiness to mean.

COVID doi: 10.3390/covid6090159

Authors: Zuri Dale Ivy Mushamiri Kelly Morris Vicky Davis Amaya Tootle Bryanna Armstrong

Long COVID, defined by the National Academies of Sciences as an infection-associated chronic condition persisting at least three months following SARS-CoV-2 infection, presents a growing public health challenge. Despite national prevalence estimates of 11 to 15 percent among U.S. adults who have had COVID-19, the general population estimates of approximately 5 to 7 percent population-level symptom burden in diverse metropolitan areas remain insufficiently characterized. A cross-sectional survey was administered to adults residing in Houston and Harris County. Participants self-reported infection history, persistent symptoms lasting at least 90 days, health status, access to care, and functional impacts. Descriptive statistics summarize infected and affected, symptom frequency, and functional limitations. Of 264 eligible respondents who tested positive for COVID and rated the worst symptoms, 92 (34.85 percent) met the operational definition of Long COVID, representing an estimated sample-based prevalence of 16.91 percent across all 544 survey respondents. Given the use of convenience sampling, this figure should be interpreted as descriptive of this sample rather than as a generalized population-level estimate. Fatigue was the most reported persistent symptom (69.32 percent), followed by brain fog (62.5 percent), shortness of breath (48.84 percent), headache or migraine (43.02 percent), and joint or muscle pain (41.38 percent). Cognitive and functional symptoms predominate over respiratory symptoms. These findings demonstrate a substantial burden of persistent, multisystem symptoms in a sample of community-dwelling urban adults, highlighting the need for longitudinal research and targeted public health strategies to address long-term consequences of SARS-CoV-2 infection in diverse metropolitan settings.

COVID doi: 10.3390/covid6090158

Authors: Ratna Sutanto Ido Narpati Bramantya Callistus Bruce Henfry Sulay Gilbert Sterling Octavius

Background: This study aims to characterise the clinical and radiological features of Posterior reversible encephalopathy syndrome (PRES) in the context of multisystem inflammatory syndrome in children (MIS-C), consolidating reported cases to aid clinicians in diagnosis, management, and future research. Methods: A systematic review was conducted, adhering to PRISMA guidelines and registered under PROSPERO (CRD420251011869). Four academic databases and grey literature sources were searched up to April 2025. Inclusion criteria were cases with confirmed MIS-C and a diagnosis of PRES supported by compatible clinical and radiological findings or reported by the original investigators when detailed imaging information was unavailable. Results: Sixteen studies encompassing sixteen pediatric cases were identified. The majority were female, with a median age of 9 years. Among patients with available data, hypertension was reported in 8 cases, seizures in 9 cases, and visual disturbances in 4 cases. MRI findings predominantly showed cortical-subcortical hyperintensities in the parieto-occipital, posterior temporal, and frontal lobes. CT was frequently normal. Radiological regression was observed in most follow-up MRIs. Reported management was heterogeneous and variably described, including treatment of hypertension and seizures when present, alongside treatment of MIS-C and other potential precipitating conditions. Favourable clinical outcomes were reported in the published cases in which outcome information was available, with a median length of hospital stay of 26 days (range: 8–45 days). PRES is a rare but clinically important neurological condition reported in children with MIS-C. MRI remains the imaging modality of choice due to its sensitivity in detecting characteristic vasogenic edema, which is often missed on CT. Conclusions: PRES has been reported in a small number of children with MIS-C, but the available evidence is heterogeneous and subject to substantial diagnostic, selection, and publication biases. The relationship between MIS-C and PRES and the prognosis of affected patients still remain to be further elucidated.

COVID doi: 10.3390/covid6090157

Authors: Anna-Liisa Mottonen Christina DeRoche Treva Reed Omid Ali Kharazmi Neha Gulia Emily Sanderson Katherine Jones

The COVID-19 pandemic lockdowns heavily impacted the stress levels of families worldwide. We examined parental stress levels regarding a variety of subtopics (including finances, schooling, and seeing extended family) in North Bay, Ontario, Canada. A mixed-method survey approach was used with a volunteer sample of 101 parents from the North Bay community. Included in the survey were 25 potential parental stressors, which parents were asked to rate in terms of their stressfulness, both during the COVID-19 lockdowns and post-pandemic. To accomplish this, participants were administered only one questionnaire, after the height of the pandemic was over, and asked to reflect on both the current time and on the time during the lockdown phase of the pandemic. General stress levels were higher after the lockdowns ended compared to during the lockdowns, indicated by 20 out of the 25 surveyed parental stressors. Four themes were identified in the qualitative data obtained from open-ended questions: ability to parent; requiring additional support; mental and physical well-being; and child-rearing. Specifically, in terms of the first theme, some parents felt that parenting had become more difficult, while others did not. With respect to theme two, many parents felt a need for support in a variety of areas, which relates to theme three, as supports were often desired to improve mental or physical well-being. The fourth theme highlighted the opportunity to spend more time at home with family and raise children according to parents’ own principles. Parents were also asked about changes in their behaviours, like gambling and alcohol use; gambling, in particular, increased during and after the pandemic compared to before. However, parents reported that the difficulty associated with continuing to parent as they did before the lockdowns was minimal, and that it did not change during or after the lockdowns. Finally, parents were asked about changes to their own mental and physical health; results were mixed, but approximately half of participants perceived positive changes in their well-being. Thus, compared to existing research, the current study provides a more comprehensive overview of stressors experienced by families in the wake of COVID-19 lockdowns. It also brings to light suggestions and recommendations from survey respondents to improve parents’ quality of life in post-COVID-19 North Bay, Ontario.

COVID doi: 10.3390/covid6090156

Authors: Rasha M. Abdel-Hamid Noha M. Mesbah Shaimaa A. Fattah Esraa S. Sayed Ahmed Basem E. Eysa Tarek Abdelkader Sallam Rasha Mohamed Shady A. Ramiz Gehan H. AboEl-Magd Khaled Raafat Gehan Hamdy May Mohsen Samy Selim Eman AlHussain A. Gawad Reham Ibrahim Siddik Omnia M. Anwer Amal Ahmed Mohamed

Toll-like receptors (TLRs) play an important role in innate immunity, mediating viral recognition, antiviral responses, and cytokine production. This study evaluated TLR7 and TLR9 expression levels in COVID-19 patients and their associations with COVID-19 infection and disease severity. A total of 134 adults were included: 94 COVID-19 patients and 40 controls. RT-PCR confirmed SARS-CoV-2 infection; TLR7 and TLR9 expression levels were determined by quantitative real-time PCR. Participants’ clinical characteristics and laboratory findings were evaluated. TLR7 and TLR9 expression levels were significantly higher in COVID-19 patients than in controls (both p < 0.001). Both markers were independently associated with COVID-19 infection by multivariate analysis (OR: 6996.516, p < 0.001; OR: 7.365, p = 0.004) and showed excellent discriminatory performance by ROC analysis (AUC: 0.973 and 0.937, both p < 0.001). Among COVID-19 patients, TLR9 expression and ALT were independently associated with moderate-to-critical disease (OR: 1.448, p = 0.030; OR: 1.092, p = 0.032). TLR9 expression and ALT showed modest discriminatory performance for distinguishing moderate-to-critical COVID-19 from mild disease (AUC: 0.623, p = 0.042; AUC: 0.641, p = 0.020, respectively), while the combined model demonstrated a slight improvement (AUC: 0.659, p = 0.008). TLR7 and TLR9 may represent potential biomarkers for distinguishing COVID-19 patients from controls, and TLR9 may provide additional information on disease severity. These findings need validation in larger, multicenter studies before clinical application.

COVID doi: 10.3390/covid6090155

Authors: Lenuța Silvia Nicoruț Timea Claudia Ghitea Rareș Cristian Daina Eleia Zina Csákvári Mădălina Diana Fehér László Fehér Lucia Georgeta Daina

Background: Transparent measurement is essential when organizational capacity is compared across public health institutions. The supplied analytic dataset did not contain repeated annual scores or indicator-level evidence for the previously proposed five-domain maturity model. We therefore conducted a reproducible cross-sectional analysis limited to the variables available in the dataset. Methods: Twenty Romanian public health directorates (PHDs)—10 in counties with a university medical center (CU) and 10 in counties without one (FU)—were compared using structural indicators, eight binary COVID-19 re-sponse measures, and a composite capacity–response index. The index was the equally weighted arithmetic mean of four sample-normalized components: employees per 100,000 inhabitants, budget per capita, previous-crisis experience, and the number of documented COVID-19 measures. Results are presented as medians and interquartile ranges. Mann–Whitney U and Fisher exact tests were used, with Holm correction within comparison families. Results: The composite index was higher in CU than FU institutions (55.0 [38.0–66.3] vs. 22.0 [19.3–31.3]; U = 93.0; p = 0.0013; Holm-adjusted p = 0.0077; rank-biserial r = 0.86). CU institutions also had larger populations, more employees, larger total budgets, higher per capita budgets, more previous-crisis experience, and more documented response measures. Employees per 100,000 inhabitants did not differ significantly. After multiplicity correction, vaccination-center involvement and communication/education were more frequently documented in the CU group. Digital platforms were recorded for only two institutions and cannot be interpreted as a digital-maturity domain. Conclusions: The available data support descriptive evidence of institutional disparities associated with the university-center context, but they do not support causal inference or validation of a maturity model. The composite index should be treated as an exploratory, sample-dependent benchmarking measure pending prospective instrument development, documented scoring rules, independent assessment, and external criterion validation. Its group difference largely reflects the four constituent components, which should remain the primary basis for interpretation.

COVID doi: 10.3390/covid6090154

Authors: Anwarud Din Noor Aqsa

Mathematical modeling has played a crucial role in epidemiological research, its importance amplified during the COVID-19 pandemic. This comprehensive review provides a five-year analysis of mathematical models developed to understand and control COVID-19 transmission. The reviewed studies include deterministic models such as SIR and SEIR frameworks, stochastic models incorporating random effects, age-structured models accounting for demographic heterogeneity, within-host models describing viral dynamics and immune responses, and hybrid, multi-strain, agent-based, and network-based approaches. A literature search was conducted across major databases, and studies were categorized by model structure, analytical methods, and data integration strategies. The review examines the predictive capabilities of deterministic models, the role of stochasticity in capturing uncertainty, and the importance of demographic structure in explaining transmission and mortality patterns. The effectiveness of non-pharmaceutical interventions and vaccination strategies is also assessed. The integration of real-time epidemiological data into modeling efforts is discussed, highlighting insights into hospitalization demand, ICU utilization, and mortality trends across pandemic waves. By analyzing the strengths and limitations of each approach, this review aims to inform future pandemic management, concluding with emerging trends, including the integration of genomic data, and future directions for the field.

COVID doi: 10.3390/covid6090153

Authors: Christiano Berleze Luiz Vinicius de Alcantara Sousa

Background: The COVID-19 pandemic simultaneously affected vascular risk and healthcare utilization. We evaluated whether monthly trajectories of Brazilian Unified Health System (Sistema Único de Saúde; SUS)-financed hospitalizations for different cerebrovascular categories changed differently during the pandemic in the municipality of São Paulo. Methods: We conducted an ecological time-series study using monthly Hospital Information System of the Brazilian Unified Health System (SIH-SUS), Department of Informatics of the Unified Health System (DATASUS) data from January 2017 through December 2021. Nontraumatic intracranial hemorrhage (I60–I62), cerebral infarction (I63), unspecified stroke (I64), and other cerebrovascular diseases (I65–I69) were included. The analytical dataset comprised 240 monthly observations. Annual IBGE population estimates were used as denominators. The primary analysis used segmented negative-binomial regression with log(population) offset, temporal trend, an immediate level change from March 2020, post-intervention slope change, and annual harmonic terms for seasonality. Poisson and negative-binomial models were compared using overdispersion diagnostics and Akaike information criterion (AIC). Residual autocorrelation, category-by-intervention interactions, alternative intervention dates, and leave-one-month-out influence were assessed. Results: A total of 60,756 hospitalizations were identified. Descriptive differences in mean annual counts between the pre-pandemic and pandemic periods were +3.7% for intracranial hemorrhage, +15.2% for cerebral infarction, −16.2% for unspecified stroke, and −27.2% for other cerebrovascular diseases. All categories were overdispersed (Pearson ratios 2.16–5.05), and AIC was consistently lower for negative-binomial models. In the primary segmented model, March 2020 was associated with an immediate 39.3% decrease in other cerebrovascular diseases (incidence rate ratio [IRR] 0.607; 95% confidence interval [CI] 0.512–0.720; p < 0.001) and a 10.0% decrease in unspecified stroke (IRR 0.900; 95% CI 0.817–0.991; p = 0.032). No statistically significant immediate level change was found for intracranial hemorrhage (IRR 1.018; p = 0.760) or cerebral infarction (IRR 0.868; p = 0.086). No category showed a significant post-intervention slope change. The formal category-by-level-change interaction was significant (Wald p = 0.004), indicating heterogeneity among categories. LjungBox tests at 12 lags showed no significant residual autocorrelation. Conclusions: SUS-financed cerebrovascular hospitalizations showed heterogeneous temporal changes during the pandemic, particularly immediate decreases in I64 and I65–I69. The findings support differences in trajectories across diagnostic categories but do not demonstrate diagnostic migration, individual biological mechanisms, or causality. Changes in care-seeking, referral, coding, diagnostic availability, and healthcare organization remain plausible but untested explanations.

COVID doi: 10.3390/covid6090152

Authors: Vanessa Matthew-Belmar Shawn Charles Larissa Mark Trevor Noel Calum Macpherson Andy Alhassan Satesh Bidaisee Hamid Reza Sodagari

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in substantial global morbidity and mortality since its emergence in late 2019. This retrospective study aims to determine the comorbidity patterns, co-occurrence networks, and associated demographic factors among 244 deceased COVID-19 cases in Grenada between 2021 and 2022. The prevalence of comorbid conditions varied considerably across diseases. Hypertension was the most frequently observed condition (41%) followed by diabetes (34.8%), and ARDS (27%). Our co-occurrence analysis revealed a densely interconnected core of cardiometabolic and respiratory conditions, particularly involving hypertension, diabetes, and ARDS. Stratified clustering analyses demonstrated that multimorbidity patterns were broadly consistent across gender but differed by age group and vaccination status, with older individuals showing more pronounced clustering of cardiometabolic conditions. Logistic regression analysis further identified age and gender as significant factors associated with the distribution of specific comorbidities, including higher odds of hypertension among older individuals. This study highlights the central role of cardiometabolic diseases and older age in COVID-19 mortality in Grenada in 2021–2022 and underscores the importance of multimorbidity structures rather than isolated conditions. We suggest early identification of high-risk multimorbidity profiles, particularly among older adults, to improve clinical management and preventive strategies during future infectious disease outbreaks.

COVID doi: 10.3390/covid6080151

Authors: Eun-Young Park

Since COVID-19, reliance on digital technology has surged, and digital literacy has gained attention as a key factor in explaining changes in how people use the Internet. However, most existing studies have focused on the general public, and there has been insufficient research on how digital literacy relates to changes in Internet usage among people with disabilities. This study examined the effect of digital literacy among people with physical disabilities on changes in Internet use on personal computers (PC) and smart devices during the COVID-19 pandemic using data extracted from the 2020 Digital Divide Survey conducted by the National Information Society Agency. The survey was conducted between September and December 2020. A total of 75,000 individuals participated, of which 2200 were disabled. Data was extracted from participants who used the Internet, and the final analysis data included the response results of 1239 individuals. The findings suggest competence is unrelated to changes in Internet use in PCs and smart environments during COVID-19. For example, use/behavior, search, email, content, life services, and economic activities are related to Internet use changes on PCs and remain static with smart devices. Social media services (SNS), networking, and social participation are negatively related to changes in Internet use on PCs and smart devices. This study extends the discourse on the role of digital literacy among people with disabilities by empirically elucidating the relationship between digital literacy and changes in Internet use among people with physical disabilities during the pandemic, drawing on a nationally representative sample. The results of this study suggest that a digital literacy education program must be developed for people with physical disabilities to lead the necessary digital life in crises such as COVID-19.

COVID doi: 10.3390/covid6080150

Authors: Rajesh Das Vigneshwar Suriya Prakash Sinnarasan Dahrii Paul Md Mujibur Rahman Sheikh Santhosh Manickannan Amouda Venkatesan

Severe coronavirus disease 2019 (COVID-19) is characterized by acute immune dysregulation, with monocytes playing a central role in driving inflammation and disease severity. However, the transcriptional and post-transcriptional regulatory mechanisms underlying monocyte dysfunction in severe COVID-19 remain unexplored. In the study, an integrative analysis of paired bulk RNA-seq and miRNA-seq datasets was performed together with independent single-cell RNA-seq (scRNA-seq) data from convalescent individuals with a history of ICU or non-ICU COVID-19. Pooled cell proportions descriptively indicated a higher proportion of classical monocytes and lower proportions of non-classical monocytes, B cells and dendritic cells in individuals with a history of ICU disease; however, none of these differences was statistically significant in patient-level analyses after multiple-testing correction. Using the miRSCAPE framework, miRNA expression was inferred at single-cell resolution and identified distinct cluster-specific inferred miRNA expression patterns. Differential expression analysis of classical monocyte populations identified 284 nominally significant differentially expressed genes between convalescent ICU and non-ICU samples. Integration of miRNA-mRNA correlation analysis with experimentally validated interactions and independent assessment highlighted a focused regulatory network centered on ZMAT3, RHOB and HLA-DQA1. Host–pathogen interaction analysis identified database-supported SARS-CoV-2-host interactions involving ORF3a-RHOB and nucleoprotein-RHPN2, with additional host–host interactions connecting RHPN2, HLA-C and HLA-DQA1. Collectively, these findings provide a computational framework for investigating inferred miRNA associations of monocyte inflammatory pathways associated with prior COVID-19 severity and highlight regulatory interactions that warrant further experimental validation.

COVID doi: 10.3390/covid6080149

Authors: Timur Tastaibek Nurlan Jainakbayev Nargiza Nassyrova

Background/Objectives: Post-COVID syndrome (PCS) remains a clinically heterogeneous condition. In patients with chronic diseases, real-world evidence is needed to describe its frequency and to identify clinical factors associated with its current presence. This study assessed the prevalence of PCS and factors associated with current PCS status among patients with chronic diseases. Methods: This observational cross-sectional study included a consecutively enrolled source clinical sample of 850 adults receiving inpatient or outpatient care in Almaty and the Almaty Region between June and December 2025. The primary analytic cohort comprised participants with documented prior COVID-19 (n = 250). PCS was assessed at study enrollment according to the national clinical protocol as current symptoms persisting for more than 12 weeks and not explained by an alternative diagnosis. Multivariable logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). COVID-19 vaccination was excluded from the primary model and evaluated only in a sensitivity analysis because vaccination timing relative to infection was unavailable. The exploratory association-based probability model was evaluated using the AUC with 95% CI, Brier score, calibration assessment, bootstrap internal validation with 1000 resamples, assessment of age nonlinearity, and decision curve analysis. Results: PCS was identified in 147 of 250 participants with prior COVID-19 (58.8%). In the revised primary multivariable model, age (OR = 1.24 per 10-year increase; 95% CI: 1.01–1.54; p = 0.040) and endocrine diseases (OR = 3.36; 95% CI: 1.69–6.98; p < 0.001) remained associated with current PCS status. The association with endocrine diseases persisted after adjustment for body mass index. The apparent AUC was 0.687 (95% CI: 0.620–0.753), and the Brier score was 0.218. Bootstrap internal validation yielded an optimism-corrected AUC of 0.655, a calibration intercept of 0.061, and a calibration slope of 0.816. Conclusions: PCS was frequent among patients with chronic diseases who had prior COVID-19. Older age and endocrine pathology were the most consistent factors associated with current PCS status. All model-performance estimates were obtained within the development sample; the model should not be used for individual prediction or follow-up planning without prospective external validation.

COVID doi: 10.3390/covid6080148

Authors: Lesego Sekwati Mavis Kolobe Malebogo Bakwena

The COVID-19 pandemic caused major disruptions to agricultural value chains in the Global South, revealing vulnerabilities in food production, processing and distribution. Global estimates reveal that the COVID-19 pandemic did, in fact, worsen food insecurity in the Global South. This paper, through a systematic literature review, clarifies the relationship between agricultural value chains and the four dimensions of food security and proposes policy paths to enhance the resilience of agricultural value chains in the Global South. The literature reveals that resilience of agricultural value chains is not an intrinsic trait, but a dynamic result of ecosystem governance. It is essential, therefore, that policy interventions move beyond simple input subsidies and toward the integration of digital financial tools and formalized relational governance to link farmers to formal markets.

COVID doi: 10.3390/covid6080147

Authors: Rachel Smid Emma MacInnis Davina Banner Piper Jackson Tammy Klassen-Ross Shannon Freeman

Working during an outbreak poses additional challenges for staff working in long-term care facilities (LTCFs). The existing literature explores the experiences of LTCF staff during the COVID-19 pandemic, but there is a paucity of research focusing on the specific challenges of working during COVID-19 outbreaks in rural and northern communities. Secondary analysis was conducted on interview transcripts from sixteen participants with experience working during COVID-19 outbreaks in northern LTCFs. Participants engaged in in-depth semi-structured interviews and shared their experiences working during COVID-19 outbreaks in the COVID-19 pandemic. Seven themes emerged through thematic analysis, including: (1) personal fear and moral distress, (2) coping with resident death due to COVID-19, (3) relationship dynamics, (4) changing workload expectations during staffing shortages, (5) resource constraints and organizational support gaps, (6) resources and support, and (7) impact of vaccinations. Findings emphasize the increased complexity of working during a COVID-19 outbreak in rural and northern communities and describe factors that shaped both the positives and negatives of the experience for staff. These findings show that rural and northern LTCFs faced additional challenges during COVID-19 outbreaks due to pre-existing resource and staffing shortages. However, we also highlight the unique strength of these communities in how they coped and supported each other through COVID-19 outbreaks. This study provides practical insights to inform improved outbreak management, including the need for region-specific guidance and support, clear communication from management, reliable access to personal protective equipment, consistent staffing, and support for grief and burnout, all while highlighting the voices of those who worked through these outbreaks.

COVID doi: 10.3390/covid6080146

Authors: Taiwo Opeyemi Aremu Olihe Nnenna Okoro Caroline Gaither S. Bruce Benson Drissa M. Toure Jon C. Schommer

Background: Local vaccine manufacturing is being pursued across Africa to improve pandemic preparedness and reduce reliance on imports. In Nigeria, where COVID-19 vaccines were largely imported, willingness to accept locally produced vaccines is important for sustainable domestic production. The objective of this study was to estimate willingness to accept a locally manufactured COVID-19 vaccine among adults in Lagos, Nigeria, and to identify demographic predictors. Methods: We conducted a cross-sectional survey of adults in Lagos State from 7 September to 16 September 2024, using a questionnaire administered in four open-air markets. The primary outcome was willingness to accept a COVID-19 vaccine manufactured in Nigeria (yes/no). We summarized respondent characteristics, tested bivariate associations using chi-square tests, and estimated adjusted odds ratios (AORs) using multivariable logistic regression. Model calibration and discrimination were assessed using Hosmer–Lemeshow testing and the area under the ROC curve (AUC). Results: Of 388 consenting respondents, 335 provided complete data (86.3%). Respondents were predominantly female (60.6%); the largest age groups were 25–34 (30.2%) and 35–44 (28.4%) years. Overall, 75.8% reported willingness to accept a Nigerian-made COVID-19 vaccine. Willingness differed by age group (p = 0.0028; trend p = 0.0002) and religion (p = 0.0403). In adjusted models, respondents aged 45–54 years (aOR 6.54; 95% CI: 1.73–24.79) and 55–64 years (aOR 4.97; 95% CI: 1.05–23.55) had higher odds of acceptance than those aged 18–24 years. Christian affiliation was associated with lower odds than Muslim affiliation (aOR 0.41; 95% CI: 0.20–0.83). Discrimination was acceptable (AUC 0.75; 95% CI: 0.69–0.80). Conclusions: Most respondents were willing to accept a Nigerian-made COVID-19 vaccine, suggesting demand-side readiness. Confidence-building strategies tailored to younger adults and implemented with faith-based and community institutions may support uptake of locally produced vaccines.

COVID doi: 10.3390/covid6080145

Authors: Joel Myerson Sandra Hale Michael J Strube Leonard Green Bridget Bernstein

The COVID-19 pandemic resulted in historically high levels of psychological distress. Significant age differences in distress were consistently observed, and they present an opportunity to identify the mechanisms driving the prosocial decision-making underlying pandemic mitigation behaviors. As predicted by the cascade model of individual and age differences in prosocial motivation, re-analyses of the data from two previous surveys revealed the positive role of prosocial motivation in pandemic decisions as well as the negative roles played by neuroticism, anxiety, and depression. Social distancing was altruistically motivated, as evidenced by its positive associations with both altruism and sympathy measures. Moreover, the increases in distancing with age and concern for close others suggests that distancing was not primarily driven by concerns regarding the personal consequences of infection. Multiple age-related positivity effects were observed in which concerns and risk assessments decreased with age. Concern for others decreased with age less than concerns for oneself, suggesting a possible basis for age-related increases in altruism. Taken together, these findings suggest theoretical linkages between the cascade model and socioemotional selectivity theory, linkages that may have implications for prosocial public health messaging.

COVID doi: 10.3390/covid6080144

Authors: Matthew Z. Dudley Janesse Brewer Roger Bernier Benjamin Schwartz Haley Budigan Ni Mary Davis Hamlin Tina M. Proveaux Daniel A. Salmon

Introduction: Community engagement offers an approach to improve our understanding of vaccine hesitancy, yet some worry that public engagement centered around controversial and politicized topics such as COVID-19 vaccines carries a risk of increasing concerns. Methods: Respondents who reported hesitance to vaccinate against COVID-19 in a December 2020 national panel survey were recruited to participate in three interactive and respectful virtual community engagement meetings. A second survey in September 2021 resampled respondents to ascertain changes over time. Of the 291 respondents to both survey waves who had been willing to participate in community meetings, 94 (32%) participated. Multivariate linear and logistic regressions were used to assess the potential impact of meeting participation on outcomes of interest. Results: At follow-up, participants had nearly double the odds of vaccinating against COVID-19 (adjusted Odds Ratio: 1.88; 95% Confidence Interval: 1.06–3.34), about one-third the odds of contracting COVID-19 disease (aOR: 0.37; 95% CI: 0.14–0.96), and increased trust in the Centers for Disease Control and Prevention (CDC) (adjusted Regression Coefficient: 4.16; 95% CI: 0.37–7.94), compared to non-participants. Most participants found the meetings unbiased (89%) and trustworthy (90%). Conclusions: The design of our community meetings to focus on learning from and supporting the decision-maker (versus only promoting “shots in arms”) improved health outcomes and increased trust. Similar meetings could improve how public health engages communities.

COVID doi: 10.3390/covid6080143

Authors: Jagdish Khubchandani Ahmad Adwan Michael Wiblishauser Refat R. Srejon Kavita Batra

Cancer survivors face an elevated risk of severe COVID-19 outcomes and were prioritized for vaccination, yet reported rates of vaccination refusal in this population vary widely. The objective of this scoping review was to map the available evidence on COVID-19 vaccination refusal among adult cancer survivors in the United States, to characterize the reported barriers and enablers, and to examine how differences in measurement account for variation in the reported estimates. PubMed, EBSCOhost, CINAHL, medRxiv, and Google Scholar were searched for studies published between 1 December 2020 and 30 April 2026 reporting primary data on COVID-19 vaccination refusal among U.S. adults with a current or previous cancer diagnosis. Findings were charted and summarized descriptively. Six sources comprising 3344 participants met the eligibility criteria. Reported refusal ranged from 7.3% to 39.0%, a more than fivefold difference, with a median of 14.7%. This variation corresponded closely to what each source measured: declination of an offered vaccine, likelihood of acceptance on a Likert scale, hesitancy assessed before vaccines were widely available, or observed non-receipt of any dose. Barriers included concerns about vaccine safety, efficacy, and interaction with cancer treatment, mistrust of science and government, and low perceived need; clinician recommendation was the most consistent enabler. Estimates of vaccination refusal in this population are not directly comparable and should be interpreted alongside the construct measured.

COVID doi: 10.3390/covid6080142

Authors: Michela Murdocca Gerardo Pepe Andrea Latini Paola Spitalieri Manuela Helmer-Citterich Federica Sangiuolo Giuseppe Novelli

MicroRNAs (miRNAs) are key post-transcriptional regulators of gene expression and play a fundamental role in host response to viral infections. SARS-CoV-2 has been shown to dysregulate host miRNA expression, potentially as a mechanism to modulate cellular pathways for its own replication or to evade immune responses. However, evidence from the literature related to the specific miRNA landscape in SARS-CoV-2 infection is conflicting and unclear. We employed an integrative multi-model approach using human nasal lung epithelial cell lines and pulmonary organoids to map miRNA expression dynamics after SARS-CoV-2 infection. Data obtained from the CALU-3 miRNAome were successively validated in other two cellular models (hAEC and hLORG), and from this comparative analysis, two miRNAs, miR-141-3p and miR-33a-5p, were found to be significantly dysregulated. These miRNAs are involved in critical pathways, including cytokine-mediated signalling, apoptotic processes and epithelial cell junction integrity. High-throughput miRNA profiling was followed by functional enrichment analysis of their predicted targets to delineate affected biological pathways. By highlighting candidate miRNAs and regulatory pathways that may contribute to disease pathogenesis, we identified robust, infection-associated hallmarks across cell models, establishing a foundation for future therapeutic strategies for COVID-19 based on the development of miRNA-guided approaches.

COVID doi: 10.3390/covid6080141

Authors: Danijela Jakovljević Aleksandar Pavlović Aleksandra Ilić Slađana Trpković Nebojša Videnović Milan Filipović Snežana Đukić Ranko Zdravković Marija Milanović Aleksandar Jakovljević

Background and Objectives: In-hospital cardiac arrest (IHCA) in critically ill patients with COVID-19 is among the most severe clinical outcomes, associated with high mortality and a significant risk to healthcare workers during cardiopulmonary resuscitation (CPR). The aim of this study was to evaluate the incidence, characteristics, associated factors, and outcomes of IHCA among COVID-19 patients treated in the intensive care unit (ICU), with particular emphasis on resuscitation outcomes and survival. Materials and Methods: A retrospective cohort study was conducted including critically ill patients with confirmed SARS-CoV-2 infection treated in the ICU of the Clinical-Hospital Center (KBC) in Kosovska Mitrovica between March 2020 and December 2022. Patients were categorized into two groups: (1) CA group—patients who experienced CA in the ICU, and (2) non-CA group—patients who did not experience CA during ICU treatment. Results: A total of 222 patients were analyzed, of whom 114 (51.4%) experienced IHCA. Patients with IHCA were significantly older, more frequently obese, and had a higher burden of comorbidities. They also exhibited more pronounced hematological and inflammatory abnormalities, including lower erythrocyte and hemoglobin levels, thrombocytopenia, and elevated leukocyte counts, fibrinogen, C-reactive protein, and procalcitonin levels. In addition, higher lactate and D-dimer concentrations were observed, along with a more frequent occurrence of hyperkalemia and hypernatremia. The predominant cause of IHCA was respiratory failure, most commonly associated with severe hypoxemia (59.6%), while non-shockable initial rhythms (asystole and pulseless electrical activity (PEA)) were most common (76.3%). Among patients with IHCA, return of spontaneous circulation (ROSC) was achieved in 11 patients (9.6%), and 3 patients (2.6%) survived to hospital discharge. Conclusions: Despite rapid response and CPR in the ICU setting, outcomes remained poor. More favorable outcomes were observed mainly in cases with potentially reversible etiologies (such as myocardial infarction and pulmonary embolism (PE)), in contrast to hypoxia-mediated CA.

COVID doi: 10.3390/covid6080140

Authors: Joise Wottrich Lucas Machado Sulzbacher Maicon Machado Sulzbacher Vítor Antunes de Oliveira Pauline Brendler Goettems Fiorin Mirna Stela Ludwig Thiago Gomes Heck Matias Nunes Frizzo

COVID-19, caused by the SARS-CoV-2 coronavirus, emerged as a global pandemic in 2020, with profound impacts on public health and a substantial burden on intensive care units (ICUs). Because critically ill patients are at increased risk of rapid clinical deterioration and death, there is a need for reliable early prognostic biomarkers to support risk stratification and optimize clinical management. Therefore, this study investigated whether clinical and laboratory parameters obtained at hospital admission could serve as prognostic biomarkers for endotracheal intubation and mortality in critically ill patients with COVID-19 admitted to ICUs. A retrospective analytical study was conducted using the medical records of 107 critically ill patients with confirmed COVID-19 admitted to ICUs. Patients were classified according to clinical outcome as survivors (n = 22) or non-survivors (n = 85). Clinical characteristics and laboratory biomarkers obtained at hospital admission were analyzed. D-dimer, lactate dehydrogenase (LDH), red cell distribution width (RDW), the AST/ALT ratio, and age were independently associated with mortality. In addition, D-dimer and LDH demonstrated moderate discriminatory performance for predicting the need for endotracheal intubation. These findings suggest that routinely available clinical and laboratory parameters obtained at hospital admission may serve as complementary prognostic biomarkers to support early risk stratification and clinical decision-making in critically ill patients with COVID-19. Nevertheless, prospective multicenter studies are warranted to externally validate these findings and further establish their clinical applicability.

COVID doi: 10.3390/covid6080139

Authors: Lilia Jannet Saldarriaga Sandoval Johans Alexanders Arica Gutierrez Zoraida Esther Pérez Chore Edwar Glorimer Lujan Segura Kasandra Nayely Arca Albarracin Evelyn Thalya Sullon Carrillo Kory Elliam García Huaman Nancy Noeli Pita Santos Lyzeth Vanessa Gutarra Calle

The aim of the study was to analyse the epidemiological characteristics of confirmed COVID-19 cases in the Tumbes region between March 2020 and December 2022. Method: An ecological design with a descriptive approach was used for the study population, which consisted of 51,421 confirmed cases of COVID-19 residing in the provinces of Contralmirante Villar, Tumbes, and Zarumilla in the department of Tumbes. Confirmed cases of COVID-19 reported in SISOVID by the Ministry of Health and the registry of confirmed cases of COVID-19 in all age groups were recorded. The sociodemographic data collected was supplemented with information available on the web platform of the National Institute of Statistics and Informatics (INEI). The data were organized into databases and analyzed using software such RStudio (versión 2024.12.1), applying epidemiological indicators (incidence, prevalence, mortality, and lethality). The epidemiological data were organized and analyzed in a database prepared in Microsoft Excel to consolidate the information through data filtering and organization. Results: Among the main findings, a decrease in incidence was observed between 2021 (7840/100,000 inhabitants) and 2022 (5721/100,000 inhabitants), although the cumulative case rate increased from 15% to 20%. The mortality rate fell significantly from 2.57 per 1000 inhabitants in 2021 to 0.33 in 2022. The highest fatality rates were concentrated among people over 60 years of age with comorbidities, especially men. Conclusion: The pandemic was unevenly distributed, affecting adults between 30 and 59 years of age, populations with pre- existing conditions, and densely populated urban areas the most. The geographic distribution of cases helped identify areas warranting priority for improving the health response. It is recommended to strengthen epidemiological surveillance, improve access to health services in densely populated areas, and prioritise care for vulnerable groups such as older adults and indigenous peoples.

COVID doi: 10.3390/covid6080138

Authors: Jyotpal Singh Payam Dehghani Rishi Thakkar Chase J. Ellingson Kevin R. Bainey G. B. John Mancini Cindy Grines Ehtisham Mahmud Shy Amlani Ross Garberich Odayme Quesada Santiago Garcia Timothy D. Henry

The COVID-19 pandemic presented a unique opportunity for researchers to use pragmatic methods to obtain information about the virus and promptly disseminate the findings for healthcare providers to utilize them. One such approach to studying patients who presented with COVID-19 and ST-Elevation Myocardial Infarction (STEMI) was the development of the North American COVID-19 STEMI (NACMI) registry. By leveraging social media and communication platforms such as WhatsApp, cardiologists across North America initiated the development of the NACMI registry within 14 days—an accomplishment which was unfathomable pre-pandemic. This was followed by ethics approval through a centralized Institutional Review Board, which led to patient consent being waived, and the use of a single coordinating center (Minneapolis Heart Institute Foundation) responsible for sites, database, and analysis. The NACMI findings were published rapidly across various media, including high-profile cardiovascular journals. Early results demonstrated an elevated mortality rate, disproportionality based on race, and angiographic differences showing unique mechanistic differences in the etiology of STEMI due to COVID-19. Additionally, NACMI provided early evidence that vaccination for COVID-19 reduced the risk of mortality in those with COVID-19 and STEMI. NACMI provided a framework for informing cardiologists early on regarding the optimal treatment of STEMI in patients with COVID-19. The lessons learned may be valuable for developing policy in future pandemics to treat patients using real-world application and routinely collected variables.

COVID doi: 10.3390/covid6080137

Authors: Domna Tichala Dimitrios Papagiannis Ourania S. Kotsiou

Due to an inadvertent omission during the submission process, an additional affiliation was not included for Domna Tichala, Dimitrios Papagiannis and Ourania S. Kotsiou in the published publication [...]

COVID doi: 10.3390/covid6080136

Authors: Marcia Liane Klauck Santos Catiele Raquel Schmidt Edna Ribeiro de Jesus Camila Xavier Dalcól Michelle Mariah Malkiewiez Gabriela Marcellino de Melo Lanzoni Darlisom Sousa Ferreira David Eduardo González Naranjo Luana Amaral Alpirez Elisiane Lorenzini

Care transition comprises integrated actions that ensure individualized, multidimensional care and became especially relevant after COVID-19 due to complications, readmissions, and fragmented healthcare delivery. The aim this study was to assess care transition care quality for post-COVID-19 patients using the Care Transition Measure (CTM-15) and its association with sociodemographic and clinical variables. This cross-sectional quantitative study included 176 post-COVID-19 patients or caregivers from a Brazilian public hospital (2020–2021). Data were collected by telephone within 30 days after discharge using a sociodemographic/clinical questionnaire and the CTM-15. The results demonstrated that care transition quality was rated as satisfactory. The highest scores were observed in health management preparation and the lowest in understanding medications. Better evaluations were associated with younger age, higher income, influenza diagnosis, and non-smoking status, whereas diabetes and chronic obstructive pulmonary disease negatively influenced care plan scores. In conclusion, care transition quality was satisfactory and influenced by sociodemographic and clinical factors, highlighting the importance of individualized discharge planning.

COVID doi: 10.3390/covid6080135

Authors: Humaira Mujeeb Steven Jones Hayley J. Lowther-Payne Fiona Lobban

The COVID-19 pandemic affected maternal mental health in the UK, increasing postpartum emotional distress. This scoping review identified forms of postpartum emotional distress (PPED) examined during the pandemic, the methodologies and assessment tools used, analytical approaches, reported limitations, future research directions, and overall findings. This review followed Arksey and O’Malley’s framework and the Joanna Briggs Institute scoping review guidelines. A comprehensive, keyword-based search strategy was applied across electronic databases, initially on 28 January 2023, and updated on 20 July 2023, and 3 September 2025. Strict inclusion criteria were used, and data from eligible studies were charted and synthesised. This review of 35 UK studies on postpartum emotional distress (PPED) during COVID-19 found a dominant focus on depression and anxiety, with other PPED forms largely neglected. Quantitative designs overwhelmingly outnumbered qualitative and mixed-method approaches. Common limitations included low sample diversity, reliance on online self-report surveys, cross-sectional designs, convenience sampling, and social-media-based recruitment. This review is the first to map research approaches used to explore postpartum emotional distress (PPED) during COVID-19 in the UK. The limitations and future research directions identified in this review highlight an urgent need for more diverse sampling, longitudinal study designs, qualitative research exploring women’s lived experience narratives of different forms of postpartum emotional distress, greater consideration of biopsychosocial factors, and evidence-based interventions.

COVID doi: 10.3390/covid6080134

Authors: Ricardo S. S. Durães Gisângela Faria de Paula Andreza C. Both Casagrande Elaine R. Neiva Cristiana C. A. Rocca Antonio P. Serafim

Background: Brazilian psychologists faced heightened occupational and emotional demands during the COVID-19 peak, yet evidence on longer-term changes in distress and self-care is limited. This repeated cross-sectional study compared psychological distress and multidimensional self-care among Brazilian psychologists at the pandemic peak (T1: April 2021; n = 578) and three years later (T2: April 2024; n = 524). Methods: Distress (DASS-21) and self-care indicators (perceived self-care, working hours, work–life balance, psychotherapy/psychiatric care) were assessed. Blockwise OLS and logistic models (M0–M3) estimated time differences; dose–response and moderation analyses used adjusted marginal means with FDR correction. Results: Anxiety and stress were lower at T2 (M3: anxiety β = −1.53; stress β = −2.08; p < 0.001), whereas depression showed no statistically significant change in fully adjusted models (β = −0.37, p = 0.456), with only a modest downward tendency evident in unadjusted and nonparametric comparisons. Clinically elevated (Moderate+) anxiety decreased robustly (OR = 0.56), while the reduction in Moderate+stress was attenuated after full adjustment (OR = 0.71, p = 0.049) and did not remain significant after FDR correction. Perceived self-care showed a dose–response association with lower distress, and stress declined most among telehealth and hybrid practitioners. Conclusions: Three years post-peak, anxiety and stress were lower, whereas depression showed no clear change in fully adjusted models, indicating heterogeneous recovery. Self-care and work conditions were key associated factors, underscoring the need for sustained workforce well-being strategies. Because the design was repeated cross-sectional, these findings reflect sample-level trends rather than within-person change.

COVID doi: 10.3390/covid6080133

Authors: Emna Mziou Aicha Hchaichi Hejer Letaief Sonia Dhaouadi Mouna Safer Rim Mhadhbi Molka Osman Khouloud Talmoudi Amenallah Zouayti Khlifi Oumaima Nawel Elmili Amine Yedess Leila Bouabid Sondes Derouiche Souha Bougatef Mohamed Kouni Chahed Nissaf Bouafif Ben Alaya

The first case of Coronavirus Disease 2019 (COVID-19) in Tunisia was reported on 2 March 2020. This study aimed to describe the epidemiological evolution of the COVID-19 pandemic in Tunisia from March 2020 to December 2022 and to assess changes in key transmission indicators across the different phases and epidemic waves. We conducted a nationwide longitudinal descriptive study based on prospectively collected surveillance data including all laboratory-confirmed COVID-19 cases reported through the national surveillance system between March 2020 and December 2022. Descriptive analyses were performed to estimate screening rates, test positivity rates, cumulative incidence rates, and the time-varying effective reproduction number (Rt). During the three-year study period, Tunisia reported a cumulative incidence of 9562.05 cases per 100,000 inhabitants. The mean daily screening rate was 38.23 tests per 100,000 inhabitants, while the average positivity rate reached 16.03%. The mean effective reproduction number was estimated at 1.14 (95% CI: 1.11–1.17). The epidemic evolved through two distinct transmission phases. The first phase, extending from 2 March to 17 August 2020, was characterized by limited community transmission mainly associated with imported cases. The second phase was marked by sustained autochthonous community transmission and comprised five epidemic waves. Between March and May 2021, genomic surveillance identified the predominance of the Alpha Variant of Concern (VOC). The fourth wave was dominated by the Delta VOC until December 2021, whereas the fifth wave, occurring in 2022, was associated with the Omicron VOC. Continuous monitoring of transmission indicators through the national surveillance system provided timely evidence to support risk assessment, guide public health decision-making, and adapt prevention and control measures throughout the different phases of the pandemic in Tunisia.

COVID doi: 10.3390/covid6080132

Authors: Giancarlo Ripabelli Angelo Salzo Roberta De Dona Antonio D’Amico Vittorio Viccione Nicandro Samprati Arturo Santagata Carmen Adesso Michela Anna Di Palma Anna Natale Romeo Flocco Manuela Tamburro

The risk of healthcare associated infections (HAIs) among hospitalized patients increased with the severity of COVID-19 disease and duration of hospitalization, especially in intensive care units (ICUs). This study retrospectively investigated HAI trends between March 2020 and December 2022 in patients with a COVID-19 diagnosis admitted to the exclusive ICU for the management of severe COVID-19 patients in the Molise region, central Italy. The clinical records of patients were anonymously coded and examined for the number of HAIs and microbiological isolations. Only infections that occurred after 48 h of ICU admission were included for descriptive, univariate and multivariate statistical analysis. Over the three-year period, 185 patients with a COVID-19 diagnosis (69.7% male, mean age 66.1 ± 10.6 years) were admitted to the hospital ICU: 50 (27.0%) in 2020, 94 (50.8%) in 2021, and 41 (22.2%) in 2022. During ICU stays, a high proportion of patients required at least one invasive device and died (97.2% and 88.1%, respectively). Death outcome was significantly associated with pre-existing comorbidities and related treatment, sex, and devices. During ICU stays, 80% received antimicrobial therapy, which was further related to death. At least one microbiological HAI was detected in 103 (55.9%) patients (76.6% male, mean age 65.4 ± 9.6 years). HAI incidence differed by year (p < 0.001), occurring in 36 (35.0%) patients in 2020, 54 (52.4%) in 2021, and 13 (12.6%) in 2022, respectively, and 80.6%, 96.0%, and 92.3% of patients died. A total of 268 isolations were observed: 99 (36.9%), 139 (51.9%) and 30 (11.2) in 2020, 2021 and 2022, respectively, and were mostly fungi in 2020 and 2022 (46.5% and 36.7%, respectively), while Gram-negative bacteria predominated in 2021 (36.7%). The study revealed higher HAI rates among patients in 2021 according to the increasing number of COVID-19 cases and related hospitalizations due to the Alpha variant at the local level, but also reflected the national epidemiology, while the decline in 2022 could be likely associated with the pandemic evolution and improvements in the management of COVID-19 patients. These findings further underline a high rate of lethality, more likely attributed to severe COVID-19 in patients with advanced age and underlying diseases, to which HAI onset could have undoubtedly contributed. The study provides useful epidemiological data regarding HAIs among critically ill COVID-19 patients during different phases of the pandemic across three years.

COVID doi: 10.3390/covid6080131

Authors: Elena Moreno-Guillamont Carmen I. Sáez-Lleó María Auxiliadora Dea-Ayuela Jose M. Soriano

The COVID-19 pandemic produced a severe and heterogeneous burden across age groups, territories and epidemic phases in Spain. Older adults experienced disproportionately high rates of hospitalization, intensive care unit (ICU) admission and death, particularly during the early pandemic waves when vaccination was unavailable. However, the relationship between surveillance-confirmed cases and severe outcomes changed substantially over time, a phenomenon termed epidemiological decoupling. This study developed and applied a novel Older-adult COVID-19 Severity Decoupling Index (O-CSDI) to weekly COVID-19 surveillance data from the 17 Spanish autonomous communities and the two autonomous cities of Ceuta and Melilla. The integrated dataset covered January 2020 to July 2023 and comprised 3496 autonomous community–week observations and 143 variables obtained from four open-access surveillance sources: ISCIII-RENAVE, Datadista/Ministerio de Sanidad, Our World in Data and the MoMo excess mortality system. However, the primary incidence- and ratio-based O-CSDI analyses were restricted to March 2020–March 2022 because open-access individual event counts were no longer structurally comparable after the transition to reduced surveillance. Data from later periods were retained only for contextual vaccination and MoMo mortality indicators. The O-CSDI quantifies the degree to which reported COVID-19 incidence became disconnected from hospitalization, ICU admission and mortality in adults aged 60–69, 70–79 and ≥80 years. The primary version of the index was based on the death-to-case ratio, while complementary versions examined hospitalization-to-case, ICU-to-hospitalization and death-to-hospitalization transitions. Results showed progressive but heterogeneous decoupling across phases, territorial units and age strata, with the strongest decoupling observed during the Omicron BA.1/BA.2 period and the highest residual mortality burden in adults aged ≥80 years. All results were interpreted as ecological, descriptive indicators rather than individual-level risks or causal estimates. These findings provide a reproducible epidemiological tool for retrospective pandemic evaluation and preparedness in ageing populations.

COVID doi: 10.3390/covid6070130

Authors: Nawaf M. Alshabibi

The COVID-19 pandemic has caused unprecedented upheaval to the worldwide transportation infrastructure and as such, has redefined trends in urban mobility. In the current research, the authors plan to compare six metropolitan areas, including Houston (Texas) and Chicago (Illinois), Singapore, Dubai (United Arab Emirates), Calgary (Canada), and Cairo (Egypt), to assess the effects of the pandemic on transit ridership during the period of 2018 to 2022. The monthly data provided by the official transit agencies was analysed using paired t-tests and correlation statistics to measure the change in the ridership and how they are related to population, urban area, and network length. The results are consistent, and the effects are a three-stage course shock, stabilization, and recovery, but as the rates of recovery are different to the governance, economic structure, and technological preparation. Digitally developed, high-income metropolises like Singapore and Dubai were a bit faster in recovery, and those that relied on cars like Chicago and Calgary showed prolonged declines. Cairo also exhibited resilience driven by necessity and did not decline because of institutional adaptation, but rather because of economic dependence. The paper suggests a three-part model of resilience, including governance, technology, and necessity, that explains these differences and how mobility systems can be changed in response to crises. These findings have both theoretical and policy implications for designing adaptive, equitable, and technology-enhanced transportation planning in the post-pandemic age.

COVID doi: 10.3390/covid6070129

Authors: Alexandra Isabelle D. Ang Alexandra P. Lee Junie B. Billones Lyre Anni E. Murao Maria Constancia O. Carrillo Stephani Joy Y. Macalino

RNA-dependent RNA-polymerase (RdRp), one of the key enzymes in the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) life cycle, is a recognized druggable target for Coronavirus disease 19 (COVID-19) treatment. Its inhibition has been associated with reduced viral loads in infected individuals. A library of 1562 Philippine Natural Compounds was screened in silico for potential SARS-CoV-2 anti-RdRp activity using a high-throughput virtual screening (VS) approach. Molecular docking experiments and in silico absorption, distribution, metabolism, and excretion (ADME) predictions were used to determine compounds with potential inhibitory capabilities against RdRp. The top three compounds, Vitelignin A (VIT), Vitexoside (VIX), and Cannabifolin C (CAN), were subjected to molecular dynamics (MD) simulations in complex with RdRp, confirming the formation of stable protein-ligand complexes. Overall, these results suggest promising inhibitory capabilities of these three compounds against SARS-CoV-2 RdRp. Their shared presence in extracts of Vitex negundo, a Philippine medicinal plant, warrants further in vitro and in vivo investigation regarding the anti-SARS-CoV-2 activity of its extracts and active components.

COVID doi: 10.3390/covid6070128

Authors: Erhan Özmen Süleyman Kaan Yalçin

The COVID-19 pandemic transformed online and distance learning from a supplementary educational option into a central component of education systems, bringing anxiety, stress, and psychological well-being to the forefront of digital learning research. This study traces the two-decade evolution of research on anxiety and stress in online and distance learning between 2005 and February 2026 and examines the thematic reorientation associated with the COVID-19 period. Bibliometric mapping of 243 Web of Science (WoS) records was used to identify publication trends, intellectual structures, international collaboration patterns, and thematic developments. Piecewise analysis indicated a significant post-2020 break in annual scientific output, with the growth rate increasing nearly eightfold (p = 0.0015). Thematic evolution showed that pre-pandemic studies mainly focused on technology acceptance, computer anxiety, and learner adaptation, whereas pandemic and post-pandemic research shifted toward mental health, psychological well-being, social isolation, technostress, and resilience. China and the United States dominated scientific production, while Australia and Saudi Arabia showed notable mobility in collaboration networks. Overall, the findings suggest that the COVID-19 period was associated with a field-level reorientation toward an interdisciplinary psychosocial agenda for future online education.

COVID doi: 10.3390/covid6070127

Authors: Diane Price Banks Marissa Claudio Sasha Vergez Nadine Etienne

This study investigated the perceptions and practices of disinfectant use among students at the City University of New York (CUNY) before, during, and after the peak of the COVID-19 pandemic, with a focus on behaviors observed following a controversial statement made by President Donald Trump in April 2020 suggesting the potential use of disinfectants as a treatment for a SARS-CoV-2 infection. Utilizing an online survey of 441 CUNY students, data was collected on cleaning and disinfection behaviors during four distinct periods: pre-pandemic (January–February 2020), during the pandemic’s height (March–April 2020), after the pandemic’s height (June–August 2020), and following the aforementioned presidential statement. Data patterns illustrate an increase in cleaning frequency and disinfectant use during the peak of the pandemic, followed by a notable decrease after the presidential statement. The data also illustrated potentially dangerous practices, such as misting the body with cleaning sprays and using household cleaners on bare skin, though these behaviors generally decreased after the peak of the pandemic. The study highlights the impact of public health communication and the role of misinformation in shaping hygiene practices during a crisis. It underscores the need for clear, evidence-based messaging to promote safe and effective disinfectant use and to counter misinformation that may lead to harmful behaviors. This novel research contributes to the understanding of how a specific student population responded to the pandemic and provides insights for future public health interventions.

COVID doi: 10.3390/covid6070126

Authors: Nurah Alamro Turki M. Alhakbani Abdullah AlDhuwaihy Abdulrahman AlOmar

Background: Public acceptance of vaccines during emerging infectious disease outbreaks is influenced by perceptions of safety, accessibility, and cost. Understanding these determinants during the early phase of a pandemic is important for informing vaccination policy and communication strategies. This study examined the role of vaccine cost and safety perceptions in shaping COVID-19 vaccination intention among adults in Saudi Arabia prior to national vaccine rollout. Methods: A cross-sectional electronic survey was conducted among adults residing in Saudi Arabia between August and September 2020. Participants were recruited through online distribution using social media and electronic communication channels. The questionnaire assessed socio-demographic characteristics, knowledge and perceptions regarding COVID-19, and intention to receive COVID-19 vaccination under five hypothetical scenarios reflecting vaccine cost and the availability of scientific safety and efficacy evidence. Multivariable logistic regression analyses were performed to identify factors associated with vaccination intention. Results: A total of 1293 respondents completed the survey. When vaccination was offered free of charge, 57.5% of participants reported that they would likely receive the vaccine. Vaccination intention declined as the hypothetical vaccine price increased, reaching 38.7% when the cost exceeded 100 SAR. Intention was lowest when vaccination was presented under conditions in which safety and efficacy evidence had not yet been confirmed. Age, gender, educational attainment, and prior seasonal influenza vaccination were associated with COVID-19 vaccination intention across several scenarios. Conclusions: Perceived vaccine affordability and confidence in scientific safety and efficacy evidence were important factors associated with COVID-19 vaccination intention during the early phase of the pandemic in Saudi Arabia. Providing vaccination without direct cost to recipients and communicating safety and efficacy evidence transparently may support public confidence and vaccine acceptance during future large-scale immunization campaigns. These findings should be interpreted as an early-pandemic baseline and should not be extrapolated to current post-rollout attitudes.

COVID doi: 10.3390/covid6070125

Authors: Marilena Mousoulidou Nektarios-Alexandros Damianou Andri Christodoulou Loukia Taxitari Konstantina Zamba

Background: The COVID-19 pandemic underscored the importance of understanding the psychological factors associated with engagement in recommended health behaviours. This study examines how decision regret and conspiracy mentality relate to vaccination engagement and protective health behaviours during the later stages of the COVID-19 pandemic in Cyprus. Methods: A total of 325 Greek-speaking adults completed an online questionnaire that included demographic questions, the Decision Regret Scale (DRS), the Conspiracy Mentality Questionnaire (CMQ), and a COVID-19 Preventive Behaviours Questionnaire developed by the authors. Results: The findings showed that: (a) greater vaccination engagement and protective health behaviours were associated with lower levels of decision regret; and (b) conspiracy mentality was associated with vaccination engagement but not with protective health behaviours. Conclusions: The findings highlight the potential relevance of emotional processes such as decision regret and belief-related factors, such as conspiracy mentality, in relation to engagement with recommended health behaviours. These findings may help inform public health communication strategies aimed at supporting engagement in recommended health behaviours during future health crises.

COVID doi: 10.3390/covid6070124

Authors: Sofia Teodora Muntean Andreea-Raluca Cozac-Szoke Andreea Cătălina Tinca Diana Maria Chiorean Adrian Horațiu Sabău Iuliu Gabriel Cocuz Raluca Niculescu Claudia Raluca Mariean Nadja Emily Pop Ovidiu Simion Cotoi Anca Ileana Sin

Background: Persistent cardiovascular and multisystem manifestations remain an important concern following hospitalization for coronavirus disease 2019 (COVID-19). However, the spectrum of newly identified conditions during follow-up and their relationship with acute disease severity remain incompletely characterized. This study aimed to describe cardiovascular and multisystem diagnoses, identified during short-term and long-term follow-up and to evaluate the association between acute-phase clinical characteristics, biomarkers, and subsequent outcomes. Methods: We conducted a retrospective observational cohort study including 762 adults hospitalized with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between January 2021 and December 2022. Follow-up data were obtained from patients who re-presented to the same hospital during short-term follow-up (mean 4.33 months; n = 130) or long-term follow-up (mean 2.06 years; n = 186). Newly documented cardiovascular and non-cardiovascular diagnoses recorded during routine clinical care were analyzed separately for each follow-up cohort. Multivariable logistic regression was used to identify predictors of in-hospital mortality and cardiovascular outcomes. Results: At least one newly documented diagnosis was identified in 120/130 patients (92.3%) during short-term follow-up and in 175/186 patients (94.1%) during long-term follow-up. Cardiovascular diagnoses were identified in 32.3% and 45.2% of patients attending short-term and long-term follow-up, respectively. Hypertension and atherosclerosis were the most frequent cardiovascular diagnoses during short-term follow-up, whereas heart failure and ischemic heart disease predominated among patients attending long-term follow-up. Pulmonary fibrosis was the most common non-cardiovascular diagnosis at both follow-up periods. Elevated D-dimer and fibrinogen levels during acute COVID-19 were independently associated with in-hospital mortality, whereas acute-phase NT-proBNP was not independently associated with cardiovascular diagnoses identified during follow-up. Conclusions: Patients who re-presented for clinical evaluation after hospitalization for COVID-19 exhibited a substantial burden of newly documented cardiovascular and multisystem diagnoses. Given the retrospective design, independent follow-up cohorts, and absence of a non-COVID control group, these findings should be interpreted as observational post-hospitalization data rather than evidence of causal or progressive post-COVID-19 disease. Prospective controlled longitudinal studies are needed to better define the long-term health consequences of SARS-CoV-2 infection.

COVID doi: 10.3390/covid6070123

Authors: Katerina Papavasileiou Verónica Marín María José Noguera-Marín

The present study takes place in the context of the COVID-19 pandemic and the Greek economic crisis, in which the health systems reached their limit and the physical and psychological exhaustion of professionals increased, testing supportive leadership in hospitals. An ex post facto, descriptive, and correlational study was designed, with non-probabilistic sampling, applied to 741 health professionals from public and private hospitals located in Attica and Piraeus. An 18-item ad hoc questionnaire was used, validated through an exploratory factor analysis (KMO = 0.805; 4 dimensions) and with a high reliability (α = 0.87). The staff showed a moderately positive assessment of the leadership and the supervisor dynamics, but a low enjoyment of work during the crisis. The hypothesis of generalized stress was discarded, with differences found according to gender (more conflict and less recognition perceived by women) and age (more conflicts between the supervisors and younger staff), without important differences according to level of education or work position. It can be concluded that support, psychological capital, and work relations, appeared as relatively independent constructs, modulated by organizational and personal factors, which underlines the need for specific interventions oriented towards the well-being and recognition of health professionals in contexts of crisis.

COVID doi: 10.3390/covid6070122

Authors: Caitlin Slomp Anna MacLellan John R. Best Zainab Naqqash Boyee Lin Cynthia Lu Mizuki Kubota Zahra Ofoghi Hasina Samji S. Evelyn Stewart

Canadian youth experienced profound impacts to mental health (MH) support throughout the COVID-19 pandemic. Given the risk for long-term negative outcomes from unmet MH needs, it is critical to understand access barriers. The purpose of this study was to explore the longitudinal data and personal narratives on MH challenges, needs and access barriers. The Personal Impacts of COVID-19 Survey was administered to parents regarding their youth at baseline (November 2020–July 2021) and follow-up (November 2021–October 2022). Semi-structured interviews of selected youth and parents were conducted. Quantitative data from 507 baseline surveys, 177 follow-up surveys and qualitative data from 35 interviews were included in the study. A modified explanatory sequential/nested mixed methods design was used to analyze the data. Results showed that the use of MH supports among youth increased between timepoints, although 20% had persisting unmet needs for MH supports at follow-up. Youth described waitlist barriers and difficulties finding the “right” therapist, and parents described significant difficulties navigating the MH system that profoundly impacted their families’ ability to access care and mitigate negative MH outcomes. Increased clinician availability, school MH supports, parental education, and tools for navigating the MH system are needed to better support families.

COVID doi: 10.3390/covid6070121

Authors: Salvador E. Ayala-Raggi Rafael Alejandro Cruz-Ovando Lauro Reyes-Cocoletzi Aldrin Barreto-Flores

This paper presents an automatic classification system for pulmonary diseases in chest X-rays based on geometric normalization. The proposed method consists of three main modules. Module 1: A landmark detector: A ResNet-18 convolutional neural network with coordinate attention mechanism is trained to predict 15 landmarks defining the lung contour, achieving a mean error of 3.61 pixels (median 3.07 pixels) through an ensemble of four models with test-time augmentation. Module 2: Geometric normalizer: a set of landmarks surrounding the lung region is used to geometrically normalize each image. This normalization involves: Generalized Procrustes Analysis used once to obtain a standard lung shape, Delaunay triangulation to build a deformation mesh, and a piecewise affine transformation (warping) to map the original lung region to a standardized region. This process eliminates variations in position, scale, and orientation in the original set. Module 3: Classifier: normalized images are classified into three categories (COVID-19, Viral Pneumonia, and Normal) using a ResNet-18 classifier with transfer learning and a contrast adjustment (using the SAHS (Statistical Asymmetrical Histogram Stretching) method). The classifier was evaluated through five-fold cross-validation on the COVID-19 Radiography Database, demonstrating high stability with 98.60 ± 0.26% accuracy, and 98.00% F1-Macro, confirming the robustness of the approach. Although the classifier trained with original images reached a higher accuracy than using normalized images, Gradient-weighted Class Activation Mapping (Grad-CAM) analysis and the cropping experiment suggest that this advantage is partly driven by acquisition artifacts rather than lung pathology. In contrast, geometrically normalized images outperform their non-aligned artifact-masked/cropped counterparts: 98.60% vs. 96.24% on the COVID-19 Radiography Database and 94.67% vs. 94.17% on a balanced adult–pediatric mixed dataset including pediatric cases from the Kermany dataset, suggesting that anatomical alignment can yield a more reliable and artifact-resistant representation for pulmonary disease recognition.

COVID doi: 10.3390/covid6070120

Authors: Liya Vajdi Dmitriy Klyuyev Olga Ponamareva Zeine Kulbayeva Ahmadreza Vajdi Bo Hu

Background: Long COVID is a heterogeneous post-viral condition in which persistent neurological, autonomic, cognitive, and psychometric symptoms often occur without clear isolated biomarker abnormalities. This mismatch suggests that disease persistence may be driven not only by changes in individual markers, but by longitudinal reorganization of biological and clinical interactions. Materials and Methods: This observational longitudinal study evaluated patients with persistent symptoms after confirmed SARS-CoV-2 infection at 3 and 6 months. Clinical assessment included neurological examination, Hospital Anxiety and Depression Scale, Beck Depression Inventory, and COMPASS-31. Biomarkers representing hypoxia signaling, oxidative/redox stress, endothelial and renin–angiotensin system activity, glycation-related processes, and complement regulation were analyzed. Correlation analysis, association-level biomarker–clinical network modeling, and complementary Graphical LASSO-based sparse network estimation were used to compare network density, community organization, centrality, and edge rewiring between time points. Results: Conventional paired analysis identified HIF-1α as the only continuous variable with a statistically significant longitudinal change (Wilcoxon statistic = 610.0, p=0.000350), whereas association-level network analysis revealed a broader systems-level signal. The association-level biomarker–clinical network preserved a similar global size at 3 and 6 months, with 16 nodes, 27 versus 26 edges, and densities of 0.225 versus 0.217. However, this apparent stability concealed substantial rewiring: 19 edges were shared, 8 were lost, and 7 emerged. Complementary Graphical LASSO analysis with 1000 bootstrap resamples supported this pattern by identifying a conservative sparse conditional-dependency core, including seven shared conditional-dependency edges across time points and selective weakening of four early conditional dependencies. The C3–C4 relationship reversed from negative to positive correlation (r=−0.618 to r=0.618), indicating marked remodeling of complement-associated regulation. A psychometric–autonomic module involving Beck, HADS I, HADS II, and COMPASS-31 remained stable across both assessments. Conclusions: Long COVID progression was characterized by dynamic remodeling of immune, endothelial/RAS, oxidative-redox, hypoxia-related, autonomic, and psychometric interactions. Longitudinal network analysis identified a systems-level interaction structure that was not captured by isolated biomarker comparisons alone and that was further supported by complementary sparse conditional-dependency analysis.

COVID doi: 10.3390/covid6070119

Authors: Andres González-Zapata Andrés Arias-Sánchez Roberto Henríquez Katlheen Velez Leonardo Escobar Andres Rojas-Gulloso Emmanuel Eroume A Egom

During the SARS-CoV-2 pandemic, healthcare systems faced an increased burden of secondary infections, including those caused by Candida auris, an emerging multidrug-resistant pathogen associated with hospital outbreaks worldwide. We aimed to describe the clinical and microbiological characteristics of a hospital outbreak of Candida auris fungemia in patients with COVID-19 in a tertiary care center. This retrospective observational study included 14 patients diagnosed between November 2020 and April 2021. Infection was initially identified using VITEK2® and confirmed using MALDI-TOF MS, with antifungal susceptibility determined using broth microdilution. All patients developed fungemia, were mechanically ventilated, and had central venous access and prolonged hospital stays; 64.2% had comorbidities. Resistance frequencies based on CDC tentative MIC thresholds were observed for fluconazole (64.2%) and amphotericin B (71.4%). In-hospital mortality was 50%; exploratory analyses of factors associated with mortality should be interpreted cautiously given the small sample size. These findings highlight the significant clinical impact of Candida auris in critically ill COVID-19 patients, particularly in the context of invasive care and antimicrobial resistance. The outbreak underscores the importance of early identification, appropriate antifungal therapy, and strict infection prevention and control measures. Further studies are needed to better define risk factors and optimize management strategies in similar settings.

COVID doi: 10.3390/covid6070118

Authors: Adam B. Smith Philip G. Conaghan Christine Comer Manoj Sivan Sarah R. Kingsbury

Background: Post-COVID-19 syndrome or Long COVID (LC) is a multi-system condition characterised by persistent symptoms beyond three months following SARS-CoV-2 infection. Pain, particularly musculoskeletal and neuropathic pain, is commonly reported and may substantially affect functioning and health-related quality of life (HRQoL). However, there is limited detailed characterisation of pain phenotypes and their differential impact on outcomes in LC. This study aimed to (i) characterise pain associated with LC, (ii) identify factors associated with pain type and severity, and (iii) examine its impact on HRQoL, physical activity, and work. Methods: A cross-sectional survey was conducted among adults with clinician-diagnosed or self-reported LC who reported current or previous joint, muscle, or nerve pain. Participants completed validated patient-reported outcome measures including the C19-YRS, Nordic Musculoskeletal Questionnaire, Pain Detect Questionnaire (PD-Q), Musculoskeletal Health Questionnaire, and EQ-5D-5L. Participants were classified into neuropathic, nociceptive, or ambiguous pain groups based on PD-Q scores. Descriptive analyses, group comparisons, and backward stepwise ordinary least squares regression were used to examine factors associated with overall pain (PD-Q Total). Results: Among 198 participants (73% female; mean age 52 ± 12.7 years; mean LC duration 2.4 years), 96% reported new or worsened pain following COVID-19 infection, with muscle pain (87%), joint pain (84%), and nerve pain (66%) most frequently reported. PD-Q scores suggestive of neuropathic pain were identified in 28% of participants and were associated with significantly greater pain intensity, symptom burden, functional impairment, and lower HRQoL (p < 0.05). These participants reported higher average pain scores across all body regions and greater radiating pain (76%) compared to other groups. Functional disability and anxiety were significant factors associated with pain severity. Conclusions: Pain is highly prevalent in LC, with neuropathic pain representing a distinct and more severe phenotype associated with substantial functional and quality-of-life impacts. This study provides novel comparative evidence on pain phenotypes and their differential burden, highlighting the need for targeted pain assessment and management strategies in LC.

COVID doi: 10.3390/covid6070117

Authors: Joseph Amazuwa Chirwa Emmanuel George Yusufu Lloyd George Banda

While conventional theories posit that stronger institutions buffer economies against crises, the COVID-19 pandemic presents a puzzle: despite substantial variation in institutional capacity, the global economic contraction of 2020 was both severe and widespread. Motivated by this puzzle, we constructed a global panel dataset from 2014 to 2024 and employed two-way fixed-effect estimation with Driscoll–Kraay robust standard errors to examine the differential role of state capacity across COVID-19 crisis phases. The results confirm that the shock caused by the pandemic reduced GDP per capita growth across countries, with the Americas experiencing disproportionately deeper contractions and stronger rebounds relative to other regions. Most importantly, the findings reveal a temporal asymmetry in institutional effectiveness: our constructed composite resource-based measure of state capacity does not mitigate the initial economic contraction but exerts a positive, statistically significant effect on post-pandemic recovery. Unsurprisingly, model re-estimation with the conventional perception-based measure of state capacity fails to replicate this dynamic, underscoring the importance of measurement strategy in institutional research. These results challenge the assumption that institutions uniformly buffer shocks, demonstrating instead that state capacity is more consequential for recovery than crisis prevention.

COVID doi: 10.3390/covid6070116

Authors: Mª Pilar Rodríguez-Pérez Sandra León-Herrera Raquel Gómez-Bravo Elisabet Huertas-Hoyas Sara García-Bravo Pilar Rodríguez-Ledo Cristina García-Bravo

Post-COVID condition is frequently associated with persistent fatigue, reduced functional capacity, and loss of independence in activities of daily living. Exercise intolerance and post-exertional symptom exacerbation limit participation in conventional rehabilitation programs, highlighting the need for safe and scalable home-based interventions. The REACT-COVID project aims to evaluate the feasibility, safety, and potential effects of a home-based intervention combining whole-body electromyostimulation (WB-EMS) with functional activities of daily living in individuals with post-COVID condition. This study will be a randomized, placebo-controlled, participant-blinded pilot trial including 30 participants allocated to either an experimental group receiving active WB-EMS or a control group receiving sham stimulation over a 12-week period. The primary aim is to assess feasibility, safety, and acceptability. As exploratory clinical outcomes, fatigue severity (Chalder Fatigue Questionnaire, CFQ-11) and functional capacity (Six-Minute Walk Test, 6 MWT) will also be evaluated. Secondary outcomes include handgrip strength and independence in activities of daily living (ADLQ). Assessments will be conducted at baseline (week 0), post-intervention (week 12), and three-month follow-up (week 24). This intervention is designed to provide a low-mechanical-load, accessible alternative for individuals unable to tolerate conventional exercise programs. This study’s findings will inform larger multicenter trials and contribute to scalable rehabilitation models for post-COVID care. Trial registration number: ClinicalTrials.gov (NCT07312357).

COVID doi: 10.3390/covid6070115

Authors: María Teresa Hernández-Galindo Adriana González-Hernández Cruz Vargas-De-León

Background: The COVID-19 pandemic was accompanied by an infodemic that promoted the use of so-called “miracle products” lacking scientific evidence, posing significant public health risks. Despite increasing concern, evidence on effective educational strategies to counteract this misinformation remains limited, particularly in Latin America. Methods: A quasi-experimental pre–post study without a control group was conducted among university students in Mexico City between February and June 2021. Participants were recruited via Facebook using a snowball sampling approach. A validated nine-item questionnaire assessed knowledge about miracle products before and after exposure to an educational video intervention. Paired statistical analyses were performed to evaluate changes in knowledge. Results: A total of 157 participants completed the pre-test, and 103 completed the post-test. The intervention resulted in a significant increase in knowledge scores, from a mean of 5.98 (SD = 1.73) to 9.05 (SD = 1.54) (p < 0.001). Significant improvements were observed in eight of nine items, with the largest increases in knowledge related to high-risk substances and reporting mechanisms. No significant baseline differences were found between participants who completed and those who did not complete the post-test. Conclusions: The video-based educational intervention was effective in improving knowledge about miracle products during COVID-19. These findings support the use of digital health education strategies as scalable tools to combat misinformation, particularly in resource-constrained settings. However, further research using controlled designs is needed to assess long-term effects and behavioral outcomes.

COVID doi: 10.3390/covid6070114

Authors: Lateef Olalekan Bello Dorah Dubihlela

The COVID-19 pandemic prompted the introduction of South Africa’s Social Relief of Distress (SRD) grant to mitigate income shocks among individuals excluded from existing social programs. This study utilizes a three-year national representative dataset from the General Household Survey and applies a fixed effects regression framework to estimate the association between COVID-19 SRD grants and unemployment. The findings indicate a positive and statistically significant association between grant receipt and unemployment. Specifically, the results suggest that grant recipients are approximately 27–32% more likely to be unemployed than non-recipients. The findings suggest that while the grant provided necessary initial financial relief, in the absence of complementary labour market interventions, income support alone may be insufficient to address unemployment. The study concludes by recommending the coordination of temporary income relief integrated with active labour market policies to promote sustainable employment outcomes.

COVID doi: 10.3390/covid6070113

Authors: Da-In Park

Background: During the recent COVID-19 pandemic, nursing students faced heightened infection risks during clinical practicum while managing significant psychological demands. However, factors predicting the preventive practices of future healthcare professionals remain poorly understood. Methods: This cross-sectional study examined 261 nursing students on COVID-19 knowledge, attitudes, practices, psychological distress, self-efficacy, and resilience during the fourth wave of the COVID-19 pandemic in South Korea. Grounded in the Knowledge–Attitudes–Practice (KAP) framework, hierarchical multiple regression analysis was conducted to identify predictors of preventive practice behaviors. Results: Depressive symptoms (β = 0.27, p = 0.023) and resilience (β = 0.29, p < 0.001) were significantly positive predictors of COVID-19 preventive practice. Conclusions: Resilience emerged as the strongest predictor of COVID-19 preventive practice among nursing students, highlighting the importance of psychological resources in sustaining infection prevention behaviors. Nursing education programs should incorporate resilience-building strategies to strengthen pandemic preparedness and clinical readiness among future healthcare professionals.

COVID doi: 10.3390/covid6070112

Authors: Vera Beca Fatjon Balla Daniela Nakuci Zahide Sulejmani Marsilda Danaka Enver Roshi Eliona Demaliaj

Background: SARS-CoV-2 infection during pregnancy has been associated with adverse maternal and neonatal outcomes, particularly in severe disease. However, evidence stratified by disease severity from Southeastern Europe remains limited. The aim of this study was to compare obstetric and neonatal outcomes between mild and severe COVID-19 among pregnant women managed in tertiary maternity hospitals in Tirana, Albania. Methods: A retrospective multicenter observational study was conducted between January 2020 and December 2022 in the two main tertiary maternity hospitals in Tirana. Pregnant or postpartum women with RT-PCR-confirmed SARS-CoV-2 infection were included. COVID-19 cases were classified as mild or severe according to clinical presentation and oxygen saturation. Maternal, obstetric, and neonatal outcomes were analyzed and multivariable logistic regression was used to evaluate associations between disease severity and selected outcomes. Results: A total of 270 pregnant women were included, of whom 212 (78.5%) had mild COVID-19 and 58 (21.5%) severe disease. The mean maternal age was 29.4 years and most infections occurred during the third trimester (80.8%). Severe COVID-19 was associated with significantly higher odds of NICU admission (aOR 2.87, 95% CI 1.36–6.05), Apgar score < 7 at 5 min (aOR 8.39, 95% CI 1.49–47.35), low birth weight (aOR 2.53, 95% CI 1.06–6.03), and emergency cesarean section (aOR 8.10, 95% CI 2.64–24.86). Maternal age, obesity, parity, and comorbidities were not significantly associated with the examined outcomes. Conclusions: Severe COVID-19 during pregnancy was associated with poorer neonatal condition at birth and increased obstetric intervention, highlighting the importance of close monitoring and coordinated obstetric–neonatal management in pregnancies complicated by severe SARS-CoV-2 infection.

COVID doi: 10.3390/covid6070111

Authors: Sadia Z. Shah Parthkumar Satashia Shahin Isha Patrick Johnson Katie Kunze Abdul Moiz Khan Jorge Sinclair Rose Mary Attieh Anirban Bhattacharyya Ricardo Diaz Millian Michael Anthony Edwards Rickey E. Carter Leigh Spiecher Pablo Moreno Franco Devang Sanghavi Hani M. Wadei

The Omicron variant of SARS-CoV-2 is associated with milder symptoms and lower hospitalization and mortality rates than Delta variants, although the impact of Omicron on immunocompromised patients, especially solid organ transplant (SOT) recipients, is still unclear. This study compares the hospitalization rate and outcomes between immunocompromised, immunocompetent, and SOT patients during the Delta and Omicron periods. We included adult patients who tested positive for SARS-CoV-2 on PCR or nasopharyngeal antigen test between 26 June 2021 to 8 September 2022, at our institution. A total of 12,401 COVID-19 patients were included, of which 11,055 were immunocompetent, and 1346 were immunocompromised (375 SOT recipients). Throughout the Delta and Omicron outbreaks, immunocompromised patients exhibited higher comorbidities and 30-day hospitalizations, but rates of mechanical ventilation and ICU-level care were like immunocompetent patients. During the Omicron wave, immunocompromised patients had higher unadjusted relative risk estimates (RR = 2.37, 95% CI 1.96–2.87, p < 0.05) than Delta (RR = 1.58, 95% CI 1.24–2.01, p < 0.05), with higher adjusted relative risk for hospitalization in Omicron (RR = 1.50, 95% CI 1.10–2.03, p = 0.01). Analyses show increased hospitalization risk in immunocompromised during the Omicron wave compared to the Delta wave, with no significant difference in hospitalization outcomes. The relative risk of hospitalization for SOT patients was higher in both waves.

COVID doi: 10.3390/covid6070110

Authors: José Ángel Hernández-Mariano Tania Alí Sánchez-Torres Antonio Gutiérrez-Ramírez Alejandra Valdivia-Flores Erika Gómez-Zamora Ricardo Castrejón-Salgado Marco Antonio León-Mazón Agustina Rosas-Baruch María G. Ortiz-López

Background: COVID-19 during pregnancy has been associated with various obstetric complications; however, epidemiological evidence regarding its relationship with hypertensive disorders of pregnancy (HDP) and preterm birth remains inconclusive. Therefore, we aimed to evaluate the association between COVID-19 during pregnancy and the risk of HDP and preterm birth among Mexican pregnant women. Methods: We conducted a retrospective cohort study based on a review of 3710 medical records of women treated at a tertiary hospital between 2020 and 2023. COVID-19 was diagnosed by real-time reverse transcription polymerase chain reaction (RT-PCR) assay. We estimated adjusted risk ratios (aRRs) using robust Poisson regression models, controlling for potential confounders. Results: The COVID-19 rate was 2.5%. We observed that women with COVID-19 had a higher risk of HDP (aRR = 1.59; 95% CI = 1.07–2.36). When HDP subgroups were analyzed separately, COVID-19 was associated with an increased risk of preeclampsia (aRR = 2.04; 95% CI = 1.34–4.20) and preterm birth (aRR = 1.50; 95% CI = 1.02–2.19). The association with gestational hypertension lost statistical significance after adjustment. Conclusions: Our findings suggest that COVID-19 during pregnancy may be associated with hypertensive disorders of pregnancy and preterm birth. However, the observed association with preeclampsia should be interpreted cautiously because diagnostic overlap between severe COVID-19 and preeclampsia cannot be excluded.

COVID doi: 10.3390/covid6070109

Authors: Elena Moreno-Guillamont Carmen I. Sáez-Lleó María Auxiliadora Dea-Ayuela Jose M. Soriano

Background/Objectives: The health status of institutionalized older adults is determined by the interaction of functional, cognitive, nutritional, anthropometric, and biochemical factors, which may not be adequately captured through single-domain assessments. Within the framework of the VIVA Project (Vulnerability Index: Valencia institutionalized Adults), this study aimed to characterize institutionalized older adults during the COVID-19 pandemic using an integrated multidimensional approach and to explore clinically interpretable vulnerability profiles. Methods: This cross-sectional study included 124 residents from 10 nursing homes of Valencia, Spain. Data were obtained from institutional records and included age, sex, body mass index (BMI), Barthel Index, Mini-Examination of Cognition (MEC), Tinetti scale, Mini Nutritional Assessment-Short Form (MNA-SF), and biochemical markers related to protein status, lipid metabolism, micronutrient availability, and renal function. An exploratory VIVA multidimensional index was constructed from nine standardized variables, and k-means clustering was applied to these variables rather than to a single summed score to identify residents’ phenotypes. An exploratory logistic regression model was used to assess the internal discrimination of the high-vulnerability phenotype. Results: The cohort showed marked heterogeneity across functional, cognitive, nutritional, anthropometric, and biochemical domains. Cluster analysis identified three clinically interpretable phenotypes ranging from lower to higher vulnerability. Functional impairment, particularly the Barthel Index and Tinetti score, was the main driver of separation between phenotypes, while biochemical markers contributed to refining profile discrimination. The exploratory logistic regression model showed high internal discrimination for the high-vulnerability phenotype, supporting the internal coherence of the integrated framework. Conclusions: An integrated multidimensional framework may be useful for characterizing vulnerability among institutionalized older adults and supporting risk stratification in long-term care settings. The logistic regression findings, including the high AUC, should be interpreted only as evidence of internal discrimination and internal coherence of the exploratory construct, not as evidence of external validity, reproducibility, diagnostic accuracy, or future predictive utility.

COVID doi: 10.3390/covid6070108

Authors: Xhevat Jakupi Norma P. Tavakoli Malësore Zogaj Thaqi Gylden Kreka Agnesa Blakaj Nazmi Mehmeti Rina Hoxha Sanije Gashi Arsim Kurti Berna Ibrahimi Arlinda Jakupi Rubik Hajdari Besfort Kryeziu Isme Humolli Donjeta Pllana Hajdari

Introduction: From 12 March 2020, when the first cases of COVID-19 were registered in Kosovo, to 9 March 2023, there were a total of 273,310 reported cases of COVID-19 and 3211 reported deaths in Kosovo (CFR: 1.17%). Health care workers (HCWs) have been at a higher risk of contracting SARS-CoV-2 infection; nevertheless, data on seroprevalence of SARS-CoV-2 antibodies among HCWs in Kosovo are very limited. Methodology: A cross-sectional serology study with 1654 healthcare professionals throughout Kosovo was conducted to determine the presence of antibodies against the spike antigen of SARS-CoV-2. In addition, a structured questionnaire was administered to study participants to obtain basic demographic data, and information on prior infection and COVID-19 vaccination status. Results: Antibodies against the spike antigen of SARS-CoV-2 were detected in almost all (99.8%) HCWs that participated in the study. The average antibody titer was 8030.8 AU/mL in women and 9533.7 AU/mL in men. Sixty-four percent of HCWs in this study reported prior infection with SARS-CoV-2, 6% of whom were hospitalized. Over 98% of study participants had received SARS-CoV-2 vaccination. Conclusions: Almost all HCWs participating in the study had antibodies against the spike antigen of SARS-CoV-2. This is most probably the result of the high COVID-19 vaccination rate in Kosovo as well as infection with SARS-CoV-2.

COVID doi: 10.3390/covid6070107

Authors: Gerusa Luciana Gomes Magalhães Marcia Regina Eches Perugini Marsileni Pelisson Fernanda Esposito Evelyn Poliana Candido Julia da Silva Pimenta Nilton Lincopan Eliana Carolina Vespero

Introduction: Several Enterobacterales species harboring New Delhi metallo-β-lactamase (NDM-1) have been reported worldwide. Among them is Providencia stuartii (P. stuartii), an emerging pathogen in nosocomial infections. Objective: This study aimed to perform the clinical and genomic characterization of NDM-1-producing P. stuartii isolates recovered from hospitalized patients during the COVID-19 pandemic in Southern Brazil. Materials and Methods: A retrospective observational study was conducted between April and September 2021 at a Brazilian teaching hospital. Fifty P. stuartii isolates were identified, and carbapenem-resistant isolates underwent phenotypic and molecular characterization. Genetic relatedness was assessed by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR), and selected isolates were subjected to whole-genome sequencing using the Illumina NextSeq platform to determine sequence types, resistance genes, virulence determinants, and plasmid content. Statistical analyses were performed using SPSS version 20.0. Results: Among the 50 isolates, 21 (42%) harbored the blaNDM-1 gene. Most isolates were recovered from tracheal aspirates (57.2%), followed by blood (23.8%), urine (9.5%), and skin and soft tissue samples (9.5%). Significant associations were observed between NDM-1-producing isolates and SARS-CoV-2 infection (p = 0.013), central venous catheter use (p = 0.012), mechanical ventilation (p = 0.006), hemodialysis (p = 0.033), previous antimicrobial exposure, and mortality (p = 0.021). Genomic analysis revealed the presence of blaNDM-1, blaOXA-1, and multiple resistance determinants associated with aminoglycosides, fluoroquinolones, macrolides, tetracyclines, and folate pathway inhibitors. ERIC-PCR demonstrated low genetic variability among isolates, suggesting possible clonal dissemination within the hospital environment. Conclusions: This study reports the emergence of NDM-1-producing P. stuartii during the COVID-19 pandemic in a Brazilian teaching hospital. The low genetic variability among isolates and the multidrug-resistant profile highlight the potential for nosocomial dissemination and reinforce the importance of genomic surveillance and infection control strategies.

COVID doi: 10.3390/covid6060106

Authors: Gulomjon Kholov Nilufar Akhmedova Ulugbek Ochilov Gulruh Khayrullayeva Otabek Yuldashev

Background: Endothelial dysfunction and renal injury are emerging as a common feature of long COVID, especially in those with hypertension. It is not yet well characterised whether SARS-CoV-2 infection exacerbates podocyte dysfunction, fibrotic signalling and renal hemodynamic remodelling, over and above the effects of hypertension alone and there are no reliable early biomarkers in this population. Methods: We conducted a comparative cross-sectional study with prospective 6-month treatment response follow-up in 120 adult patients (aged 30–60 years) with essential hypertension (Stage I, II or III; n = 40 per stage), at Bukhara Regional Multidisciplinary Hospital. Each stage subgroup was further divided into post-COVID (3–6 months after recovery; n = 20) and non-COVID (n = 20) strata. Patients with diabetes, known chronic kidney disease, previous myocardial infarction or stroke and other major comorbidities were excluded. Serum cystatin-C, creatinine, aldosterone, TGF-β1 and VEGF-A; urinary nephrin and microalbumin; cystatin-C-derived eGFR (CKD-EPI) and oral protein-loaded renal functional reserve (RFR); and renal Doppler indices (Vps, Ved, RI, PI) of the main, segmental and interlobar arteries were assessed before and after 6 months of guideline-based renin–angiotensin–aldosterone system (RAAS) blockade (enalapril 5–10 mg or azilsartan 40–80 mg, ±eplerenone). Comparisons were made by Student’s t-test—associations by Pearson correlation. Results: At baseline, post-COVID hypertensive patients exhibited consistently higher endothelial–podocyte injury markers than non-COVID counterparts. Urinary nephrin was elevated across all stages (Stage I: 126.5 ± 9.1 vs. 91.9 ± 8.3 pg/mL, p < 0.01; Stage III: 203.3 ± 11.2 vs. 164.5 ± 9.7 pg/mL, p < 0.05), as were VEGF-A (Stage III: 286.1 ± 16.4 vs. 223.2 ± 12.6 pg/mL, p < 0.01) and TGF-β1 (Stage III: 186.4 ± 10.1 pg/mL, 1.3-fold higher; p < 0.01). The detection of microalbuminuria was 100% in Stage III post-COVID patients and 85% in non-COVID controls. The post-COVID groups had selective loss of renal functional reserve (7.8 ± 1.1% in Stage III compared to 12.5 ± 1.6% in non-COVID controls, p < 0.001). Nephrinuria correlated strongly with RFR (r = −0.824, p < 0.001), eGFR (r = −0.797, p < 0.001) and aldosterone (r = 0.613, p < 0.001). Six months of RAAS blockade reduced nephrinuria, microalbuminuria and TGF-β1 in both arms but the magnitude of biomarker reduction appeared smaller in the post-COVID group, particularly in Stage III. Conclusions: Long COVID appears to be associated with persistent endothelial dysfunction and podocyte injury in hypertensive patients. These results indicate that nephrinuria, VEGF-A, TGF-β1 and renal functional reserve are potential exploratory markers of endothelial and renal abnormalities in hypertensive patients following COVID-19. Before clinical utility can be determined, larger studies with multivariable modelling, diagnostic-performance analyses and correction for multiple testing are needed. The differences in biomarker response between groups observed in this study need to be confirmed in larger prospective studies with multivariable modelling and formal interaction analyses.

COVID doi: 10.3390/covid6060105

Authors: Gunter Wolf

The German author Hans Erich Nossack (1901–1977) wrote the novel “On Call: A Report on the Epidemic” four years before his death. This fascinating novel has yet to be translated into English. It depicts a bleak future in which a mysterious global epidemic erupts. The focus is on an unnamed first-person narrator, a chemist in a so-called on-call unit. His task is to recover the numerous bodies left behind by the epidemic. In a matter-of-fact, almost emotionless tone, he reconstructs the course of the catastrophe in retrospect. The disease is an anomaly: it is a kind of ‘suicide epidemic’ in which people apparently die or take their own lives for no apparent reason. The reasons for this remain unclear, intensifying uncertainty and a sense of helplessness within society. The novel describes in great detail fundamental changes in individual psychology and global society, revealing striking parallels nearly 50 years later during the worldwide COVID-19 pandemic. This paper seeks to compare the suicide pandemic described in the novel with today’s COVID-19 pandemic. To the best of my knowledge, this association has not been previously described. Similarities between the novel and the pandemic will be analysed. Nevertheless, there are also fundamental differences between the novel’s plot and the COVID-19 pandemic. In addition, some basic information about the author Nossack (a rather complex personality), likely not well-known to non-German-speaking readers, will be provided. The goal of this contribution is to familiarise non-German-speaking readers with this novel and its author. Finally, I will briefly mention Aaron Antonovsky’s concept of salutogenesis, which focuses on building resilience, resources, and supportive environments to manage disease. Nossack’s “Bereitschaftsdienst” anticipates key questions in salutogenesis—particularly the importance of finding meaning, comprehensibility, and coping strategies in the face of existential threats—but explores them within a far darker and more sceptical framework.

COVID doi: 10.3390/covid6060104

Authors: Sajjad Hussain Muhammad Mubeen Saeed Ahmad Qaisrani Shah Fahad Muhammad Suffian Muhammad Tahir Hafiz Muhammad Rashad Javeed Wajid Nasim

The world has already been facing food, nutrition, and security challenges for the last few decades. The coronavirus 2019, COVID-19, has a significant impact on food security and agriculture, such as affecting food demand and the food supply chain, with the greatest consequences on the most vulnerable population. This review provides a comprehensive overview of the effects of COVID-19 on global agriculture and food security, drawing on recent scientific publications, institutional reports, and policy documents from 2020 to 2026. The review examines the impact of the pandemic on cropping patterns, fruit and vegetable harvests, availability of farm inputs, connectivity of the agricultural system, food supply chains, food demand, and labor availability. Vegetable and fruit markets were most affected due to the spread of COVID-19. Due to the closing of markets and restaurants, produce distributors and farmers were required to transfer supplies entirely from the food production to the marketplace. These effects are additionally being felt in agriculture and food security. Almost 55% of researchers indicated that COVID-19 has the most impact on agriculture and its complete harvest during the season, and an additional 45% stated that COVID-19 has adversely affected food security. However, food has slowed down well to date in numerous nations. The spread of COVID-19 is beginning to disrupt the supply of agricultural products and food to consumers and the marketplace across and within borders. The different spring crops, such as sunflower, canola, maize, barley, spring wheat, and various field vegetables, cannot be grown during COVID-19. Consequently, COVID-19 has had a binding effect on the food supply chain and agriculture due to the disruption, which the government should have addressed promptly.

COVID doi: 10.3390/covid6060103

Authors: Heru Wijono Fauna Herawati Abdul Kadir Jaelani Stefani Kartika Octavia Dewi Ramdani Nur Palestin Ayumuyas Azminah Kevin Kantono Rika Yulia

This study analyses the pharmacological profiles of medications administered to critically ill COVID-19 patients to evaluate their efficacy regarding recovery rates and duration of hospitalization. The results demonstrate a significant difference in clinical outcomes. While the administration of Ceftazidime, Ceftriaxone, and Oseltamivir was associated with negative survival trends, Dexamethasone and Favipiravir were associated with a fourfold higher probability of survival in severe cases. Notably, no pharmacological intervention significantly reduced the length of hospital stay; instead, recovery duration was primarily influenced by comorbidities such as obesity, cardiovascular disease, and diabetes. Furthermore, age and preexisting physiological conditions remained primary predictors of mortality. Observational analysis in our study for drug repurposing identified Amikacin, Remdesivir, and Rivaroxaban as potential therapeutic candidates. However, Dexamethasone was identified as the most effective treatment for recovery, likely due to a molecular structure with high potential binding affinity to the SARS-CoV-2 virus. These findings suggest that while specific repurposed drugs offer measurable benefits, patient history remains a critical determinant of outcomes, highlighting the necessity for further research to refine therapies against emerging viral pathogens.

COVID doi: 10.3390/covid6060102

Authors: Jesus Alonso-Carrillo Cristina de la Calle Pilar Parra Maria Ruiz Rodriguez Estibaliz Arrieta Ortubay Ana Roca Mario Diaz Santiañez Antonio Lalueza Rocio Garcia-Garcia Carlos Lumbreras Bermejo Maria Ruiz-Ruigomez

Objective: Long COVID (LC) has been defined as a chronic condition that occurs after SARS-CoV-2 infection and persists for more than 3 months. Dyspnea is the most common and disabling symptom with several mechanisms identified. The pathophysiology of post-COVID dyspnea is unknown. The aim of this study is to analyze the clinical profile of patients presenting with dyspnea in the context of LC and to assess its possible relation with complementary diagnostic tests. Material and Methods: This is a retrospective cohort study including adult patients diagnosed with LC attending a post-COVID outpatient clinic. Dyspnea was assessed using mMRC and Borg scales. Complementary tests included chest imaging, pulmonary function tests (PFTs) and a six-minute walk test (6MWT). These assessments were performed at several time points throughout follow-up (3, 6, and 12 months). Results: Eighty patients diagnosed with LC were included, the mean age was 60.0 ± 14.4 and 43 (54.8%) were female. Most patients were hospitalized during acute infection (97.5%) and 25 patients experienced respiratory failure. During the follow-up, chest X-rays showed persistent abnormalities in 67.5% of patients, and 6MWT was pathological in 61.3% at 277 days (IQR 176–326) after acute infection. No significant differences were observed in the prevalence of ventilatory failure across dyspnea severity categories. Reduced DLCO was observed in 20% of patients, while obstructive or restrictive patterns were infrequent. Through three follow-up visits, pulmonary function and exercise capacity remained stable, with modest improvements in DLCO and exercise-induced desaturation (p = 0.005). In multivariable analysis, obesity (adjusted OR 7.88; p = 0.023) and lower DLCO (p = 0.049) were independent predictors of more severe dyspnea, highlighting the role of non-pulmonary factors in Long COVID. Conclusions: This study describes the clinical and functional profile of a cohort of patients with LC. Although abnormal findings were frequent, only impaired DLCO and obesity were independently associated with dyspnea severity, while imaging and six-minute walk test abnormalities showed no consistent association with symptom intensity, supporting a multifactorial origin of post-COVID dyspnea.

COVID doi: 10.3390/covid6060101

Authors: Pablo del Pozo-Herce Eva García Carpintero-Blas Antonio Martínez-Sabater Elena Chover-Sierra Iván Santolalla-Arnedo Regina Ruiz de Viñaspre-Hernández Vicente Gea-Caballero Teresa Sufrate-Sorzano Michał Czapla Raquel Maria Martinez-Pascual Raúl Juárez-Vela Alberto Tovar-Reinoso

The COVID-19 pandemic placed unprecedented pressure on healthcare systems and frontline professionals, particularly nurses, highlighting the importance of understanding their emotional experiences and coping strategies. This study aimed to explore the emotional experiences and coping strategies of nursing professionals during the first wave of the COVID-19 pandemic in a Spanish regional healthcare setting. A qualitative descriptive phenomenological study was conducted in 2020. Data were collected through semi-structured interviews and written narratives from 36 nursing professionals working in the Riojan Health Service. Three main themes emerged: perceived emotions, stressors, and coping strategies. Nurses reported intense feelings of fear, uncertainty, and frustration, which negatively impacted their mental health and hindered emotional regulation and decision-making. Key stressors included high workload, lack of resources, constant exposure to risk, and rapidly changing clinical situations. Despite these challenges, participants described various coping strategies, such as peer support, professional commitment, and adaptive emotional responses, which helped them manage the situation. The findings describe the emotional impact experienced by nursing professionals during the first months of the COVID-19 pandemic and identify coping strategies used in a specific regional healthcare context in Spain.

COVID doi: 10.3390/covid6060100

Authors: Kauane Vieira de Oliveira Luana dos Santos Andrade Davi Vantini Laércio da Silva Paiva Fernando Luiz Affonso Fonseca Rosangela Filipini

Background: Home care (HC) has expanded globally, offering individualized care and reducing hospital demand, but the role of the family caregiver imposes a significant physical and emotional burden, particularly during health crises like coronavirus disease 2019 (COVID-19). This study aimed to analyze the performance and quality of life perspectives of family caregivers during the pandemic. Methods: A cross-sectional, descriptive and quantitative study was conducted with 101 family caregivers from the Better at Home Program in Santo André, Brazil, between February and March 2021. The World Health Organization Quality of Life-BREF (WHOQOL-BREF) instrument was used to assess quality of life, and the Barthel Index was used to evaluate the degree of patient dependence. Results: The sample showed a predominance of women (mean age 56 years, SD = 12.541; 13.9% aged 20–40 years, 41.4% aged 43–59 years, 44.7% aged 60–84 years) convenience sample, with low education and family income up to two minimum wages. Most caregivers were fully dedicated to patients with high dependence (89.1% in total or severe dependence, mainly due to neurological disorders). Overall quality of life was classified as “needing to improve” or “regular” in 61.4% of cases, with the pandemic intensifying perceived difficulties and negatively impacting all quality of life domains. A high prevalence of untreated chronic diseases and low COVID-19 vaccination rates were concerning findings. Conclusions: Family caregivers represent a vulnerable population requiring public policies and integrated support strategies, including quality of life assessment, psychological support, financial assistance, and respite care to ensure continuity of humanized, quality care.

COVID doi: 10.3390/covid6060099

Authors: Morgana Maciél Oliveira Yuri Clemente Andrade Sokolovicz Marieli Friedrich Loreto Gilson Zeni Tales A. C. Goulart Patrick Teixeira Campos Isabella Burchardt Ferreira Carlos Serpa Otávio Augusto Chaves Davi Fernando Back

Research on oxazolones, particularly 4-alkynyloxazolones, has garnered increasing interest due to the presence of an alkynyl group, which facilitates molecular conjugation and enables diverse chemical modifications. In this study, three representative 4-alkynyloxazolone derivatives (L1–L3) were synthesized and structurally characterized through single-crystal X-ray diffraction and computational analysis to obtain a reliable structure of L1–L3 to subsequently predict in silico interactions with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein. The crystallographic results revealed high molecular planarity and multifurcated hydrogen bonding. Considering the obtained crystallographic structure, theoretical descriptors such as HOMO–LUMO energy gaps and electrostatic potential maps indicated that these compounds exhibit favorable electronic reactivity, particularly for L3, with favorable drug-like predictions. The lack of methoxy groups in L2 and L3 makes these compounds have lower predicted toxicity parameters than L1. Molecular docking calculations targeting SARS-CoV-2 spike glycoprotein in three different feasible conformations in a biological matrix, i.e., three receptor-binding domains (RBD) in down conformation, two RBD in down and one in up conformation, as well as RBD bound to the human receptor angiotensin-converting enzyme 2 (ACE2), suggested strong binding affinities and specific interactions with the RBD moiety, mainly in the up conformation. Overall, this work integrates crystallographic and computational approaches to establish the structural and in silico evaluation of spike-binding properties of early substituted 4-alkynyloxazolones, suggesting L3 as a candidate for future in vitro antiviral assays.

COVID doi: 10.3390/covid6060098

Authors: Lambros Tsourgiannis Vasilios Zoumpoulidis George Drosatos Stavros Valsamidis

This study identifies the factors that influence the use of the Airbnb platform by Generation Z and Y in Greece, classifies them into groups according to their attitudes, and profiles the tourists of each generation according to their preferences regarding Airbnb bookings. The researchers conducted a primary survey using a sample of 576 citizens. Factor analysis was conducted initially to identify the main factors that affect each generation in using Airbnb after the COVID-19 pandemic. Cluster analysis was performed to classify each generation into groups. Quadratic discriminant analysis was conducted in the third phase to check cluster predictability. Non-parametric tests, including the chi-square test, were performed to profile tourists of each generation according to their preferences regarding Airbnb bookings. The results of this study indicate that people of Generations Z and Y preferred to use Airbnb accommodations even after the COVID-19 pandemic. The fact that Airbnb is safer than a conventional hotel due to COVID-19, the easy booking process and access to house amenities, as well as other marketing issues, affects most people of Generation Z and Y. This market segmentation study is quite essential in the tourism industry, especially in a country where tourism is of great importance to its economy. It highlights the impact of the pandemic on decisions and attitudes regarding the use of Airbnb.

COVID doi: 10.3390/covid6060097

Authors: Evangelia Kartsoni Nikolaos Bakalis George Markakis Sanna Ruhalahti Michail Zografakis-Sfakianakis Evridiki Patelarou Athina Patelarou

This study aimed to investigate the factors that predict the acceptance of distance learning among undergraduate nursing students during the COVID-19 pandemic and to examine Please check if the Citation part is missing the implications of these findings for nursing education in the post-pandemic era. A cross-sectional study was conducted in Greece with a convenience sample of undergraduate nursing students from the Hellenic Mediterranean University and the University of Patras. Data were collected between December 2020 and January 2021 using an online questionnaire. Statistical analysis was performed using IBM SPSS version 21.0. A total of 378 undergraduate nursing students (mean age: 22 years) participated in this study. The regression model predicting students’ attitudes toward distance learning (ATel) was statistically significant and explained 18.3% of the variance in ATel scores (R2 = 0.183, adjusted R2 = 0.158). Among the psychological and experiential factors, future career concerns (β = 0.237, p < 0.001), emotional distress related to social isolation (β = 0.186, p = 0.001), and perceived difficulties in group work (β = 0.140, p = 0.013) were revealed as significant predictors of the students’ attitudes toward distance learning. In contrast, digital readiness, flexibility, and perceived effectiveness of distance learning were not revealed as statistically significant predictors in the multivariate model but were positively associated with students’ attitudes. Demographic characteristics were not identified as statistically significant predictors of ATel scores. Psychosocial factors were significantly associated with nursing undergraduate students’ attitudes toward distance learning, underscoring the importance of incorporating blended learning in higher education in the post-pandemic era to secure group interaction, effective collaboration, and students’ well-being.

COVID doi: 10.3390/covid6060096

Authors: Toni Valković Sandra Bašić-Kinda Aron Grubešić Marija Stanić Damić Ozren Jakšić Stefan Mrđenović Sabina Novaković-Coha Dominik Lozić Mirta Mikulić Ranka Serventi Seiwerth Dino Dujmović Barbara Dreta Gordana Pavliša Marino Narančić Ida Hude-Dragičević Igor Aurer

During the pre-Omicron phases of the COVID-19 pandemic, patients with hematological neoplasms were characterized by very high morbidity and mortality rates. Remdesivir, a viral RNA-polymerase inhibitor, interferes with key SARS-CoV-2 enzymes, preventing the virus from multiplying. The use of convalescent plasma (CP) in treating patients with COVID-19 has been shown to be beneficial in patients with an impaired humoral response to infection, including most of those on active treatment for hematologic malignancies. This retrospective, non-interventional study was performed using the Croatian Cooperative Group for Hematological Diseases database of patients with hematological malignancies infected with SARS-CoV-2. Patients treated with remdesivir and/or CP were matched to those untreated according to age, disease type, and antineoplastic therapy. We identified 119 patients treated with remdesivir and/or CP fulfilling entry criteria and matched 116 according to our established criteria to one of the 374 untreated patients. Treatment significantly reduced COVID-19 mortality. The beneficial effect of antiviral therapy was limited to those who started antiviral treatment within 7 days of the onset of symptoms. Due to the exclusive enrolment of hematological patients with COVID-19, our study provides unique insights into the benefits of early application of both antiviral and CP therapy. It emphasizes the need for early administration before the infection has transformed into the hyperinflammatory phase.

COVID doi: 10.3390/covid6060095

Authors: Madalina Maria Diac Andrei Scripcaru Nona Girlescu Marin Fotache Bogdan Malinescu Daniel Tabian Sofia Mihaela David Laura Riscanu Diana Bulgaru Iliescu

Introduction: The global spread of the SARS-CoV-2 pandemic led to a serious health, social and economic global crisis. This pandemic was and remains the most important health emergency worldwide, for which all professionals have been called to provide diagnosis and treatment support. Despite early concerns about safety, forensic medicine has contributed to a better understanding of the pathological mechanisms involved. Objective: This study aims to describe and analyze the postmortem pathological findings in confirmed SARS-CoV-2 cases, emphasizing the contribution of forensic autopsies to elucidating the mechanisms of death and associated comorbidities. Methods: A retrospective study was conducted on 279 autopsies between 2020 and 2022. Demographic, clinical, and pathological data were collected and statistically analyzed. Results: Following the descriptive analysis of the cases included in the study, as well as the analysis of the relevant scientific literature, the major impact of the COVID-19 pandemic was highlighted in terms of the death mechanisms involved, occurring consequences and induced changes. Conclusions: Autopsies remain the essential tools for investigating COVID-19-related deaths. The findings confirm that SARS-CoV-2 primarily affects the pulmonary and cardiovascular systems. However, the overlap between “death from” and “death with” COVID-19 highlights the need for standardized postmortem diagnostic criteria and comprehensive clinical–pathological correlation.

COVID doi: 10.3390/covid6060094

Authors: Karoline Brizola de de Souza Eduarda de Lemos Wyse Raif Gregorio Nasre Nasser Ana Paula Veber Ana Luiza Muccillo-Baisch Bruno Dutra Arbo Flávio Manoel Rodrigues da Silva Júnior Mariana Appel Hort

Alcohol is one of the most commonly consumed psychoactive substances worldwide, with university students representing a subgroup characterized by elevated consumption rates. The COVID-19 pandemic triggered significant behavioral shifts across the general population, with students particularly vulnerable to its psychosocial impacts. In this context, the present study aimed to assess alcohol consumption patterns among university students and to examine the influence of the early stages of the COVID-19 pandemic on these behaviors. A cross-sectional study was conducted between July and November 2020 using a structured, self-administered online questionnaire. Alcohol consumption was assessed through self-reported measures of use (yes/no), frequency of intake (e.g., weekly consumption), and perceived changes in consumption compared to the pre-pandemic period. The instrument also collected data on sociodemographic characteristics, health status, and COVID-19 diagnosis. A total of 1553 valid questionnaires (i.e., fully completed responses meeting inclusion criteria) were analyzed. The prevalence of self-reported alcohol consumption was 99.93%, reflecting the inclusion of individuals with any level of consumption (including occasional use). Weekly consumption was the most frequently reported pattern. Regarding changes during the pandemic, 248 students reported an increase in alcohol intake, which was considered the main outcome of the study. Students reporting a perceived decline in overall health were less likely to report increased consumption, whereas those with a confirmed COVID-19 diagnosis were more likely to report increased use. The findings reveal a high prevalence of alcohol consumption among university students and suggest that periods marked by abrupt behavioral and routine changes, such as the COVID-19 pandemic, may significantly influence substance use patterns within this population.

COVID doi: 10.3390/covid6060093

Authors: Viridiana Del Carmen-Niño Ricardo Herrera-Navarrete José Angel Vences-Martínez Mirella Saldaña-Almazán Karla Rosalba Anzaldúa-Soulé Miguel Angel Lorenzo-Santiago

Solid waste management (SWM) is a major global challenge for environmental sustainability and public health. This study analyzed SWM perceptions and practices before and during the COVID-19 pandemic in Playa Boca Chica, Tecpan de Galeana, Guerrero, Mexico, using a descriptive and quantitative approach. Data was collected from 60 households between September and October 2022 and analyzed using SPSS statistical software version 26; reliability was confirmed with Cronbach’s Alpha; and the generation-associated greenhouse gas (GHG) emissions were estimated using the SWM-GHG climate calculator. This study explored socio-environmental dynamics in informal coastal settlements through a case study in the Global South. The results showed that waste generation remained stable during the pandemic (3.25 kg/day; p = 0.116), suggesting a pattern of behavioral rigidity in which entrenched waste management practices persisted despite the global health crisis, likely due to the absence of structural environmental interventions and policy-driven behavioral incentives. The climate calculator estimated GHG emissions of 92 and 99 tons of CO2-eq/year before and during the pandemic, respectively. Residents highlighted the need for improved infrastructure, recycling, and composting, while 97% emphasized environmental education and waste separation. The absence of a local waste management policy contributes to persistent emissions, underscoring the need for integrated and sustainable SWM strategies.

COVID doi: 10.3390/covid6060092

Authors: Imane Dalichaouche Meriem Hamouda Djamel Zoughailech Aicha Eutamene Nousseiba Abed El Batoul Ahmed Rais Malak Fertaki

The COVID-19 pandemic disrupted education worldwide, including in Algeria. This study assessed knowledge, attitudes, and practices (KAP) related to COVID-19 among biology students at the University of Constantine 1, Algeria, in 2021, aiming to inform university-based prevention strategies and future epidemic preparedness. Methods: A cross-sectional study was conducted from April to May 2021 among 300 students using a structured self-administered questionnaire. Sociodemographic data and KAP scores were collected and categorized as low, moderate, or high. Associations between KAP and demographic variables were analyzed. Results: Among participants, 86% were female, with a mean age of 22 ± 2 years. About 32% reported previous COVID-19 infection, and 59% had an infected family member. The mean knowledge score was 4.71 ± 0.94 (0–6), indicating high knowledge. The mean attitude score was 5.59 ± 1.91 (0–10), reflecting moderately positive attitudes, and the mean practice score was 8.92 ± 2.26 (0–12), indicating moderate adherence. No significant correlations were observed between knowledge, attitudes, and practices. Students showed good knowledge of COVID-19, but attitudes and practices were moderate, highlighting a gap between knowledge and behavior. Targeted university-based health education and behavioral interventions are needed to improve preventive adherence and epidemic preparedness.

COVID doi: 10.3390/covid6060091

Authors: Paskalis Gunawan Siti Setiawati Gurmeet Singh Ikhwan Rinaldi

Objectives: This study aimed to estimate the prevalence of Post-COVID-19 Syndrome among older adults in Indonesia, using time-based definitions of symptoms persisting beyond >4 weeks, >8 weeks, and >12 weeks. Methods: A retrospective cohort study was conducted among 329 older patients (≥60 years) hospitalized with COVID-19 in two tertiary hospitals in Jakarta from January to December 2021. Data on risk factors and persistent symptoms were collected from medical records and interviews. Results: The prevalence of Post-COVID-19 Syndrome was 31% (>4 weeks), 18.24% (>8 weeks), and 10.64% (>12 weeks). Significant predictors included frailty (OR 2.814), immobility during hospitalization (OR up to 4.767), higher number of initial symptoms (OR 2.043), constipation, instability, and sensory impairment during follow-up. Conclusions: Frailty, symptom burden, and geriatric syndromes, particularly immobility are strongly associated with Post-COVID-19 Syndrome in older adults. Clinical Implications: Early identification of frailty, geriatric syndromes (especially immobility), and high initial symptom burden is essential for risk stratification, targeted monitoring, and implementation of preventive and rehabilitative interventions to reduce long-term post-COVID-19 complications in older populations.

COVID doi: 10.3390/covid6060090

Authors: Nilihan E. M. Sanal-Hayes Kate Slade Marie Mclaughlin Ethan Berry Emma Swift Gabrielle Humphreys Nabil Hasshim William S. Royle Lawrence D. Hayes

Background: Globally, around 400 million people are estimated to be affected by long COVID, yet treatment options remain scarce. A systematic review published in 2025 indicated that non-invasive brain stimulation may help reduce some long COVID symptoms. If repetitive transcranial magnetic stimulation (rTMS) has therapeutic potential for these patients, then a clear synthesis of the evidence is necessary to determine efficacy and potential for implementation. Methodology: This systematic review and narrative synthesis was conducted in accordance with PRISMA guidelines. The search, completed on the 4th of December 2025, covered four databases and grey literature. Studies were included if they examined long COVID and rTMS. Findings: A meta-analysis was not possible due to insufficient reported data across studies. Instead, a structured narrative synthesis was conducted on four included studies. The structured narrative synthesis of four studies indicates that rTMS is feasible and is associated with reported improvements in fatigue, mood, and cognitive symptoms in individuals with long COVID. However, all included evidence is based on uncontrolled case series and retrospective analyses, meaning no causal conclusions can be drawn and findings should be interpreted as exploratory. Conclusions: Taken together, the evidence remains preliminary and highlights the need for well-designed randomised controlled trials to assess efficacy.

COVID doi: 10.3390/covid6050089

Authors: Handan Ciftci Ramazan Sabirli Aylin Koseler Omer Canacik Emre Karsli Dogan Ercin Emin Ediz Tutuncu Ozgur Kurt

This study investigated the association between serum hypoxia-inducible factor 1-alpha (HIF-1α) levels and clinical severity in patients with coronavirus disease 2019 (COVID-19). This prospective case–control study included 91 patients with confirmed COVID-19, of whom 51 had severe-critical disease with pneumonia and 40 had mild disease without pneumonia, as well as 39 healthy controls. Vital signs, including body temperature, pulse rate, respiratory rate, oxygen saturation, and blood pressure, were recorded. Biochemical parameters such as complete blood count, D-dimer, ferritin, creatinine, urea, and high-sensitivity cardiac troponin T were analyzed. Serum HIF-1α levels were measured using ELISA. Median HIF-1α levels were 132.9 pg/mL (IQR: 131.7–138.0) in the severe-critical disease group, 137.35 pg/mL (IQR: 131.65–152.75) in the mild disease group, and 136.6 pg/mL (IQR: 132.2–162.2) in controls. Significant differences were observed between groups (p = 0.012). ROC analysis showed a discriminatory performance for HIF-1α, with a sensitivity of 89.01% and specificity of 35.90% at a cut-off value of ≤154 pg/mL for distinguishing mild disease from controls, and a sensitivity of 86.3% and specificity of 42.5% at a cut-off value of ≤141.1 pg/mL for distinguishing severe-critical disease from mild disease. HIF-1α levels decreased with increasing disease severity. HIF-1α levels were found to be associated with disease severity; however, the low AUC values indicate that this parameter has limited discriminative ability for clinical use when used alone.

COVID doi: 10.3390/covid6050088

Authors: Lam Thi Le Johnston H. C. Wong Yen Thi Truong Bich-Hanh Thi Nguyen Nguyet Thi Trinh

Background: The COVID-19 pandemic has generated widespread concerns regarding its long-term effects on children’s mental health. While numerous studies documented increased psychological distress among children during the pandemic, less is known about how children’s emotional and behavioral functioning have evolved in the post-pandemic period. Objective: This study examines patterns of children’s mental health using survey data collected in 2023 and 2025. Guided by the dual-factor model of mental health, the analysis considers both psychological difficulties and positive social functioning in order to provide a multidimensional understanding of children’s well-being. Method: Data were collected using the Strengths and Difficulties Questionnaire (SDQ-25), a widely used behavioral screening instrument assessing emotional symptoms, conduct problems, hyperactivity/inattention, peer relationship problems, and prosocial behavior. These domains were analyzed across two time points to explore patterns of change in internalizing difficulties, externalizing difficulties, and social strengths among school-age children in the post-pandemic context (N = 1262 students in 2023 and N = 575 students in 2025). Results: The findings suggest that children’s mental health after the pandemic reflects both persistent vulnerability and adaptive capacity. Emotional symptoms and behavioral challenges remain present among a proportion of children, indicating that the psychological effects of pandemic-related disruptions may extend beyond the immediate crisis period. At the same time, many children demonstrate relatively stable levels of prosocial behavior, highlighting the continued importance of positive social functioning as a protective factor for psychological adjustment. Contributions: These results underscore the importance of adopting a comprehensive perspective on children’s mental health that recognizes both difficulties and strengths. The study highlights the role of schools and families in supporting children’s post-pandemic recovery through early mental health screening, social–emotional learning initiatives, and programs that promote empathy and peer support. Such approaches may contribute to strengthening children’s resilience and long-term well-being in the aftermath of large-scale social disruptions.

COVID doi: 10.3390/covid6050087

Authors: Gulomjon Kholov Nilufar Akhmedova Ulugbek Ochilov Sukhrob Nurulloyev Sitora Mukhammadiyeva Nozima Djuraeva Otabek Fayzulloyev Abdugappor Insopov Sanobar Rakhmonova Mehriniso Ochilova Rajab Bobokalonov Akmal Djumaev Zulfiya Abulova Dildora Otajonova Mokhibegim Nematova Nigina Shukurova Navbakhor Nazarova Dildora Komilova Mehinbonu Nurmukhammedova Dilfuza Rakhmonova

Background: Hypertension is one of the most prevalent comorbidities in patients with COVID-19 and a major contributor to chronic kidney disease (CKD). Traditional kidney injury markers, including creatinine, estimated glomerular filtration rate (eGFR) and microalbuminuria, reflect renal injury only after substantial nephron loss has already occurred. Urinary podocyte proteins, such as nephrin (nephrinuria), have been suggested as early markers of glomerular barrier dysfunction; however, their clinical behavior and diagnostic value in hypertensive patients with previous SARS-CoV-2 infection are unknown. Aim: To assess urinary nephrinuria, microalbuminuria, transforming growth factor β1 (TGF-β1), aldosterone, vascular endothelial growth factor A (VEGF-A) and renal hemodynamics across different stages of hypertension in patients with and without a history of COVID-19 and to assess the response to conventional antihypertensive and nephroprotective treatment. Methods: In a prospective comparative cohort study, 120 patients (aged 30–60 years) with stage I–III essential hypertension were stratified by COVID-19 history into a post-COVID-19 group (n = 60) and a non-COVID-19 group (n = 60); within each group, 20 patients were assigned to each hypertension stage. Comparisons were performed between the post-COVID-19 and non-COVID-19 subgroups at the same hypertension stage. Serum creatinine, cystatin-C, aldosterone, TGF-β1 and VEGF-A, urinary microalbumin and nephrin and intrarenal Doppler hemodynamics were measured at baseline and after six months of guideline-based treatment. Results: Nephrinuria was markedly increased in post-COVID-19 patients in all stages of hypertension, including stage I, where serum creatinine, cystatin-C and eGFR were within the normal range (126.5 ± 9.1 vs. 91.9 ± 8.3 pg/mL, p < 0.01). Nephrinuria was strongly correlated with renal functional reserve (r = −0.824, p < 0.001), eGFR (r = −0.797, p < 0.001), microalbuminuria (r = 0.758, p < 0.001), aldosterone (r = 0.613, p < 0.001) and VEGF-A (r = 0.589, p < 0.001). Antihypertensive and nephroprotective treatment for six months decreased nephrinuria, blood pressure and TGF-β1, with more limited effects in stage III disease. Conclusions: Nephrinuria was found to be an early marker of renal involvement in COVID-19, occurring before microalbuminuria and conventional functional markers and with a greater relative difference than these markers in stage I disease, suggesting podocyte injury as an early and potentially reversible mechanism of post-COVID renal involvement in hypertensive patients. Nephrinuria seems to be a potential biomarker for early renal surveillance in this population and its prognostic role for incident CKD needs to be validated in longitudinal outcome studies.

COVID doi: 10.3390/covid6050086

Authors: Maria Mardalena Martini Kaisar Tria Asri Widowati Helen Kristin Sheila Jonnatan Sem Samuel Surja Enty Tjoa Venna Jullyanny Waty Wijaya Anita Devi Krishnan Thantry Ivonne Martin Soegianto Ali

Understanding COVID-19 transitions towards endemicity is vital by examining center-specific data within provincial and national contexts. This retrospective study aimed to enhance public health management and understanding of COVID-19 dynamics using data from Atma Jaya Catholic University of Indonesia (AJCUI) and open-source databases from Jakarta and Indonesia’s official websites from July 2020 to December 2022. Trends across data sources were compared, and correlations between positivity rates at AJCUI and Jakarta/Indonesia were assessed using linear regression. A total of 8,354,809 positive samples were analyzed nationally, showing similar trends and peaks of positivity rates across databases, with positive correlations between AJCUI–Jakarta (β = 1.154; p < 0.001; 95% CI = 0.86–1.45) alongside AJCUI–Indonesia (β = 1.262; p < 0.001; 95% CI = 0.74–1.79). Mobility restriction policies substantially reduced the positivity rate within the study period. Further analysis of AJCUI showed that higher proportions of low Ct value (≤30) were associated with increased contemporaneous positivity at AJCUI (β = 0.442; p < 0.001) and Jakarta (β = 0.319; p < 0.001), although inadequately reflected in Indonesia (β = 0.039; p = 0.589). This study highlights the potential of incorporating Ct value distributions as epidemiological indicators within surveillance systems. These findings support the importance of comprehensive laboratory data recording to better characterize COVID-19 transmission patterns across different surveillance levels, alerting policymakers to establish efficient policies.

COVID doi: 10.3390/covid6050085

Authors: Rodrigo Portes Ureshino Larissa Augusta de Sousa Rafaela Brito Oliveira Giulia Alves Saullo Pedro Henrique Zonaro Louise Newson Carla Máximo Prado Roberta Sessa Stilhano

Excitotoxicity is one of the factors that participates in neurodegeneration, impairing neuronal and glial cells’ function, and leading to the development of chronic neurodegenerative diseases. The main mechanism of action lies in the overstimulation of excitatory receptors, especially the NMDA (N-methyl-D-aspartic acid) receptor, by glutamate, which promotes a massive influx of Ca2+ that is not sufficiently buffered by the intracellular machinery, or not released by mechanisms such as Ca2+ ATPase and plasma membrane Ca2+/Na+ exchanger promoting, among other toxic effects, mitochondrial damage and an increase in reactive oxygen species (ROS). Notably, many cases reported of long COVID-19 describe significant brain alterations and neuropsychiatric disorders, including delirium, depression, etc., and patients required increased use of antidepressant or anxiolytic drugs, for example. In addition, emerging evidence links neurodegeneration as a potential long-term sequelae associated with an increased number of patients with cognitive disorders. This review analyzes data from the literature regarding brain alterations associated with post-COVID-19 syndrome and explores a potential link to the excitotoxicity pathways, due to its participation in neurodegeneration by homeostatic failure, and it is clearly present in various brain conditions, such as Alzheimer’s and Parkinson’s diseases.

COVID doi: 10.3390/covid6050084

Authors: Julian Brauchle Valentin Unger Fabian Grünig Laura Schmidberger Jan Hochweber

COVID-19-related school closures substantially disrupted students’ daily lives. While prior research has predominantly relied on externally assessed achievement data and proxy indicators of well-being, less is known about students’ own perceptions of their experiences during distance learning. This study addresses this gap, using a qualitatively informed quantitative analysis. First, open-ended responses from N = 698 students from German and Swiss schools were analyzed to identify perceived positive and negative aspects of distance learning, thereby providing experience-based indicators of how the pandemic affected students’ well-being. Quantitative content analysis revealed that students most frequently mentioned advantages such as being at home and experiencing greater independence, while common disadvantages included a lack of social contact and insufficient learning support. Second, random forest models were applied to identify individual, contextual, and background-related predictors of these perceptions. Students with stronger self-regulation skills, lower levels of procrastination, and better-equipped home learning environments were more likely to emphasize positive experiences. Conversely, younger students and those with weaker self-regulation and fewer home learning resources more frequently reported negative experiences. The findings reveal substantial variability in students’ perceptions of distance learning, shaped by learner-related, contextual, and broader background factors. They underscore the importance of fostering self-regulation and ensuring equitable access to learning resources to better prepare schools for future crises.

COVID doi: 10.3390/covid6050083

Authors: Daniela A. Marques Cristiana P. Von Rekowski Cecília R. C. Calado Luís Bento Iola Pinto

Traditional and COVID-19-specific severity scores are applied in intensive care units (ICUs) to guide decision-making and predict mortality. Since traditional severity scores (APACHE II, SAPS II, SAPS 3, and SOFA) were not originally designed for SARS-CoV-2, this study compared their performance with COVID-19–specific models (Shang-COVID and SEIMC), including a novel distinction between early (≤7 days) and late (>7 days) ICU mortality. Adult ICU COVID-19 patients from the first two pandemic waves in Portugal were included (n = 286). Six scores were calculated, and four outcomes assessed: hospital, ICU, early ICU, and late ICU mortality. Discrimination was assessed using ROC curves with AUCs, 95% CIs, and p-values. AUCs were compared using the Delong test (early vs. late ICU mortality and across scores within each wave) and the Hanley & McNeil test (between waves for each score). Traditional scores demonstrated robust mortality prediction. SEIMC performed well for hospital (AUCwave1 = 0.808; AUCwave2 = 0.724) and ICU mortality (AUCwave1 = 0.805; AUCwave2 = 0.706). SEIMC (AUCwave1 = 0.786; AUCwave2 = 0.800) and Shang-COVID (AUCwave1 = 0.617; AUCwave2 = 0.736) showed potential for early mortality prediction but require further validation and recalibration. Overall performance was superior during the first wave, likely reflecting differences in patient characteristics, viral variants, and health measures. Traditional severity scores demonstrated stable robust prediction of ICU and hospital mortality in COVID-19 cases. Disease-specific scores did not significantly outperform established models, though also showed good predictive ability in some contexts, particularly early ICU mortality. These findings highlight the need for continuous validation and recalibration of predictive tools as clinical contexts evolve.

COVID doi: 10.3390/covid6050082

Authors: Adriano Luis Fonseca Miriã Cândida Oliveira Daniela Rosana Pedro Fonseca João Pedro R. Afonso Heren Nepomuceno Costa Paixão Jairo Belém Soares Ribeiro Júnior Larissa Rodrigues Alves Tiago Vieira Fernandes Daniel Grossi Marconi Rodrigo A. C. Andraus Carlos Hassel Mendes Silva Iransé Oliveira-Silva Orlando Aguirre Guedes Claudia S. Oliveira Natasha Yumi Matsunaga Spicacci Maria Clara Real Pedro Fonseca Wilson Rodrigues Freitas Júnior Paolo Capodaglio Luis Vicente F. Oliveira

Introduction: Coronavirus disease 2019 (COVID-19) can cause persistent cardiovascular alterations, including autonomic dysfunction. Heart rate (HR) recovery (HRR) after exercise is a simple marker of autonomic modulation associated with functional capacity and clinical prognosis. Evaluating HRR during the six-minute walk test (6MWT) may help identify residual functional limitations in diverse patients. Objective: To compare pulmonary function, maximal inspiratory pressure (MIP), functional capacity, dyspnea, fatigue, and functional status in post-COVID-19 patients. Methods: This cross-sectional study included 75 adults (mean age: 47.6 ± 13.1 years; 54.7% male) who recovered from COVID-19 divided into 2 groups based on HRR 1 min after the 6MWT: delayed (≤12 beats/min); and non-delayed (>12 beats/min). Pulmonary function, MIP, exercise capacity (via 6MWT), dyspnea, muscle fatigue, and functional status were assessed. Results: Based on HRR 1 min after 6MWT, 27 (36%) participants were classified with abnormal HRR and 48 (64%) with normal HRR. There were statistical differences between the groups regarding demographic or clinical characteristics, pulmonary function, MIP, muscle fatigue, or functional status (p > 0.05). The delayed HRR group exhibited a smaller reduction in HR in first minute of recovery (ΔHR = 6 vs. 23 beats/min), higher baseline HR (p = 0.010), and greater dyspnea (p = 0.020). Furthermore, this group exhibited worse functional performance in the 6MWT, with shorter distance walked (437.33 vs. 494.27 m; p = 0.019) and a lower percentage of predicted distance (74.66 ± 12.98% vs. 82.94 ± 15.71%; p = 0.023) compared with the non-delayed HRR group. Conclusion: Delayed HRR post-COVID-19 was associated with poorer functional performance and greater dyspnea, regardless of pulmonary function. The blunted reduction in HRR after exertion suggests impaired cardiovascular autonomic modulation, possibly related to attenuated vagal reactivation, which may contribute to exercise intolerance observed in this population.

COVID doi: 10.3390/covid6050081

Authors: Cindy M. M. de Jong Bas F. M. van Raaij Louisa (M. L.) Antoni Sesmu (M. S.) Arbous Miranda (J. J. M.) Geelhoed Michiel A. de Graaf Geert H. Groeneveld Chris (S. C. H.) Hinnen Veronica R. Janssen Moniek M. ter Kuile Anna H. E. Roukens Lauran (J. L.) Stöger Maarten S. Werkman Frederikus A. Klok Bob Siegerink on behalf of the COVID-19 LUMC Group on behalf of the COVID-19 LUMC Group

Since the introduction of the Post-COVID-19 Functional Status (PCFS) scale early in the COVID-19 pandemic, the scale has been incorporated in research and clinical guidelines to assess and monitor functional status. In this explorative study, we aimed to evaluate characteristics of the PCFS scale based on its use during a 12-month follow-up of COVID-19 survivors to increase understanding of the scale over a longer period of time. Adult COVID-19 patients who were evaluated by multidisciplinary measures at 6 weeks and 12 months post-discharge at the Leiden University Medical Center (The Netherlands) were included. The distribution of PCFS scale grades, as well as descriptive patterns between PCFS grades and patient-reported outcome measures (PROMs), pulmonary function and physical function were evaluated with descriptive analyses; no statistical tests were performed due to data availability. Of the 79 included patients, 62% had a change in PCFS grade between the 6-week and 12-month follow-ups, of whom 63% improved over time. At 12 months, abnormal PROMs regarding psychological symptoms (according to clinical cut-offs), relatively lower quality of life (EQ VAS) scores, and MRC dyspnea grades ≥ 2 were observed in patients scoring PCFS grade ≥ 2. With increasing PCFS grade, a decrease in pulmonary function and physical function outcomes was observed. Higher PCFS grades (worse functional status) seemed related to worse outcomes at 12-month follow-up. Future studies are needed to investigate whether changes in PCFS grade reflect clinically relevant changes in patients’ self-perceived functioning.

COVID doi: 10.3390/covid6050080

Authors: Maya Asami Takagi Hevatib Mehmood Asef Raiyan Hoque Neli Ragina

American Indian and Alaska Native (AI/AN) communities experienced disproportionate COVID-19 morbidity and mortality, particularly in rural areas with limited public health infrastructure. This study examined primary COVID-19 information sources among AI/AN adults in rural Michigan and evaluated how trust in these sources relates to health knowledge, attitudes, and vaccination behaviors. We conducted a prospective, randomized pre-post interventional study among 273 adults at a tribal health clinic in rural Isabella County, Michigan (2022–2024). Participants were assigned to receive a culturally tailored educational video or infographic, and surveys assessed COVID-19 knowledge, vaccine attitudes, information sources, and perceived reliability. Social media was the most frequently used information source but was rated as less reliable, whereas healthcare workers (HCWs) were considered the most trusted. Reliance on HCWs and personal relationships was associated with higher baseline vaccine knowledge and greater uptake of influenza vaccination. Both educational formats resulted in modest improvements in COVID-19 knowledge and vaccine attitudes. While no consistent differences were observed between formats overall, infographic-based education was associated with greater gains in select vaccine knowledge domains among participants who relied on trusted interpersonal or clinical information sources. These findings highlight a “usage-trust gap” in rural AI/AN health communication, where frequently used information channels are not necessarily the most trusted. Culturally tailored messaging delivered through trusted clinical and interpersonal networks may enhance the effectiveness of public health communication and support vaccine uptake in underserved communities.

COVID doi: 10.3390/covid6050079

Authors: Elisa Bósquez Diana C. Oviedo-Céspedes Gabrielle B. Britton Adam E. Tratner Sofía Rodríguez-Araña Ramón Mon

Many people experienced difficulties grieving the death of a loved one during the COVID-19 pandemic. The main objective of this research was to examine the psychological manifestations of grief for people who experienced the death of a loved one between March 2020 and March 2022 in Panama. A sample of 110 participants completed an online survey including sociodemographic questions and psychological questionnaires. A subsample of twenty-six participants was interviewed about their experience of loss leading up to death, at the time of death, and after death. Results indicated that 43.6% of participants suffered from complicated grief (CG). Participants who experienced CG had more post-traumatic stress symptoms, somatic symptomatology, anxiety/insomnia, social dysfunction, severe depression, use of avoidant coping mechanisms, and more anxiety about the pandemic than participants who did not experience CG. A logistic regression analysis indicated that anxiety/insomnia symptoms, denial as a coping mechanism, and post-traumatic stress symptoms increased the likelihood of CG. For qualitative analyses, the most relevant themes that emerged were distress associated with contagion and illness, hospitalization and access to healthcare services, communication with medical staff, the impact of the news of death, inability to view the body, emotions following the loss, farewell rituals, and coping mechanisms.

COVID doi: 10.3390/covid6050078

Authors: Vidya Keshav Lesley Scott Lucia Hans Wendy Stevens

Rapid antigen tests targeting SARS-CoV-2 nucleocapsid protein were essential for decentralised testing during the COVID-19 pandemic. Independent performance evaluations are essential to support regulatory approval and inform clinical implementation, particularly in resource-limited settings. This study presents a retrospective analytical and operational evaluation of two instrument-based fluorescent immunoassays (FIAs): the PCL COVID-19 Ag Rapid FIA and LumiraDx SARS-CoV-2 Ag Test. Analytical sensitivity was determined using recombinant nucleocapsid protein and viral cultures. Clinical performance was assessed using residual clinical specimens (n = 110) with RT-PCR as a reference, stratified by cycle threshold (Ct). Operational characteristics were assessed using a structured Likert framework. Overall sensitivity was 63% (51–73) for PCL and 95% (88–99) for LumiraDx. For Ct ≤ 25, sensitivity increased to 93% and 100%. Specificity was ≥97% for both. LumiraDx maintained sensitivity (83–94%) at Ct 25–30, whereas PCL did not detect any positives in this range. The limit of detection was 39 pM (PCL) and 0.6 pM (LumiraDx). Operational usability was high for both (90% PCL, 87% LumiraDx). LumiraDx showed higher analytical sensitivity across a broader viral load range, supporting primary diagnostic use, whereas PCL was limited to high viral loads. This evaluation provides a reproducible framework for rapid diagnostic assessment during emerging outbreaks.

COVID doi: 10.3390/covid6050077

Authors: Marina Kloni Alexandros Heraclides Theognosia Panteli Alexios Klonis Panagiotis Rentzias Christos Karagiannis

Background: Post-COVID-19 syndrome (PCS) is associated with impairments in mobility, balance, and physical function, which may reduce quality of life. The 30 s Sit-to-Stand (30STS) and Timed Up and Go (TUG) tests are widely used clinical measures; however, their intra-rater reliability in older adults with PCS has not been established. Reliable outcome measures are essential for clinical assessment and rehabilitation planning. Methods: In this single-center pilot study, nineteen older adults with PCS were recruited as a convenience sample. Participants completed three trials of the 30STS and TUG tests on day one, with the protocol repeated after three days. The 30STS evaluates lower-limb strength and functional performance, while the TUG assesses balance, gait, and fall risk. Intra-class correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC) were calculated. Results: The TUG showed an ICC of 0.995 (95% CI: 0.991–0.998), SEM of 0.48 s, and MDC of 1.33 s. The 30STS showed an ICC of 0.986 (95% CI: 0.973–0.994), SEM of 0.26 repetitions, and MDC of 0.72 repetitions. Conclusions: The TUG and 30STS demonstrate excellent intra-rater reliability and appear to be feasible clinical tools for assessing functional performance in older adults with PCS. However, findings should be interpreted cautiously due to the small, single-center pilot design and single evaluator. Further research is needed to confirm generalizability across broader PCS populations and clinical settings.

COVID doi: 10.3390/covid6050076

Authors: Domna Tichala Dimitrios Papagiannis Ourania Kotsiou

Background: Understanding how demographic and clinical factors influence SARS-CoV-2 infection patterns, vaccination uptake and disease outcomes in community settings is essential for effective primary care-based public health planning. Objectives: This study aimed to investigate the distribution of SARS-CoV-2 infections among adults attending Primary Healthcare (PHC) facilities in Giannitsa, Greece, from 2020 to 2024, and to examine associations between demographic and clinical characteristics, vaccination category and disease outcomes. Methods: A retrospective analysis was conducted using data from the National Registry of Patients with COVID-19. The study included 1144 adults diagnosed with SARS-CoV-2 at PHC facilities from 19 November 2020 to 3 October 2024; all cases included in the present analysis had been confirmed by rapid antigen testing. Variables included age, gender, residence, registry-recorded underlying medical conditions, vaccination category, seasonality and clinical outcome. Results: Significant shifts in case distribution were observed across time, with younger adults predominating in 2020–2022 and older adults (61–90 years) in 2023–2024 (p < 0.001). Winter months showed higher case incidence overall (p < 0.001). Vaccination coverage increased annually, reaching 84.8% in 2024 (p < 0.001). Hospitalization/death occurred in 1.7% of patients and was strongly associated with age ≥61 years (6.0% vs. 0.3%), the presence of at least one registry-recorded underlying medical condition (9.2% vs. 0.9%) and vaccination category; specifically, hospitalization/death occurred in 10.4% of individuals diagnosed during the pre-vaccine period, 2.3% of unvaccinated individuals during the vaccination era and 0.9% of vaccinated individuals (all p < 0.001). Conclusions: Older age, underlying medical conditions and a lack of vaccination were key predictors of worse outcomes. The findings underscore the importance of strengthening vaccination outreach and targeted PHC interventions, particularly for high-risk and rural populations.

COVID doi: 10.3390/covid6050075

Authors: George Cătălin Alexandru Doina Chioran Mircea Riviș Cristina Modiga Loredana-Neli Gligor Marius Octavian Pricop Ștefania Dinu Ciprian I. Roi Cristina Dumitrescu Andreea Mihaela Kiș Tudor Rareş Olariu

Background: COVID-19 is primarily a respiratory disease, but increasing evidence suggests possible oral and maxillofacial complications. This study presents a case series of post-COVID maxillary osteonecrosis (PC-RONJ) cases from western Romania and explores the possible association between SARS-CoV-2 infection, its treatment, and this complication. Methods: We conducted a multicenter retrospective case series of two patients with recent PCR-confirmed SARS-CoV-2 infection who subsequently developed maxillary osteonecrosis (ONC) between 2021 and 2023. Clinical examination, CT imaging (including 3D reconstructions), and ENT assessment were used to assess the severity of the disease. All medical records were reviewed to identify comorbidities, details of COVID-19 treatment, and the appearance of maxillofacial symptoms. Results: Both patients had been hospitalized for severe COVID-19 and treated according to the national protocol with systemic corticosteroids, oxygen therapy, anticoagulation, and antivirals. CT scans revealed marked osteolytic destruction of the maxilla and maxillary sinus walls, with extension toward adjacent facial bones. Microbiological analysis revealed a complex polymicrobial profile, including Gram-positive and Gram-negative bacteria as well as opportunistic fungal species, consistent with a chronic biofilm-associated infectious process. Patients received surgical treatment, followed by local care and, in both cases, prosthetic rehabilitation with maxillary obturators, which improved speech, chewing, and oral function. Conclusions: This case series suggests a possible association between severe COVID-19, its treatment, and subsequent maxillary osteonecrosis in susceptible patients; however, the small number of cases precludes causal inference. To our knowledge, this is the first Romanian report describing such cases in patients without prior antiresorptive therapy. These findings highlight the need for careful use of systemic corticosteroids and vigilant post-recovery monitoring of maxillofacial complications. Further studies are required to clarify the underlying mechanisms and risk factors.