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Ana María Piqueras-Sánchez, José Francisco López-Gil, Diego Hellín-Meseguer, Juan Cabezas-Herrera, Ginés Francisco Blesa-Llaona, José Meseguer-Cabezas, Enrique Bernal-Morell, Alfredo Minguela-Puras, Francisco Mateo Piqueras-Pérez and José Antonio Díaz-Manzano
Background/Objectives: Host factors angiotensin-converting enzyme 2 (ACE2), transmembrane protease-serine 2 (TMPRSS2), furin paired basic amino acid cleaving enzyme (FURIN), and neuropilin-1 (NRP1) facilitate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry, but it is unclear whether their upper-airway expression after recovery is
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Background/Objectives: Host factors angiotensin-converting enzyme 2 (ACE2), transmembrane protease-serine 2 (TMPRSS2), furin paired basic amino acid cleaving enzyme (FURIN), and neuropilin-1 (NRP1) facilitate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry, but it is unclear whether their upper-airway expression after recovery is associated with the severity of the preceding acute illness. We examined the association between post-acute expression of these genes and previous coronavirus disease 2019 (COVID-19) severity. Methods: This multicenter cross-sectional study included 104 adults with polymerase chain reaction (PCR)-confirmed COVID-19 during the first two pandemic waves in Murcia, Spain. Nasal and/or oropharyngeal swabs were collected in the post-acute phase, at a median of 75 days after symptom onset, and transcript levels were quantified by quantitative real-time PCR. Severity was categorized using the World Health Organization (WHO) Clinical Progression Scale, and associations were evaluated using logistic regression adjusted for age, sex, and race/ethnicity. Results: In the primary analyses using continuous expression measures, none of the four genes was significantly associated with severity. In exploratory tertile-based analyses, the intermediate ACE2 tertile (odds ratio [OR] = 0.17, 95% confidence interval [CI] 0.05–0.61; p = 0.007) and intermediate NRP1 tertile (OR = 0.29, 95% CI 0.10–0.88; p = 0.030) were associated with lower odds of severe disease; no significant associations were observed for the high tertiles or for FURIN or TMPRSS2. Conclusions: Primary adjusted analyses did not reveal statistically significant associations between post-acute nasal expression of ACE2, TMPRSS2, FURIN, or NRP1 and COVID-19 severity. Because expression was measured after clinical recovery, these associations cannot be interpreted as predictors of acute severity and may instead reflect persistent molecular remodeling after more severe disease; reverse causation cannot be excluded. Longitudinal studies with acute-phase and serial post-acute sampling and healthy controls are needed.
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Background/Objectives: Evidence regarding changes in oral and oropharyngeal squamous cell carcinoma (SCC) care across the COVID-19 pandemic remains limited, particularly in Eastern Europe. This study evaluated temporal changes in surgical admission volume, operative complexity, and comorbidity burden before, during, and after the pandemic
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Background/Objectives: Evidence regarding changes in oral and oropharyngeal squamous cell carcinoma (SCC) care across the COVID-19 pandemic remains limited, particularly in Eastern Europe. This study evaluated temporal changes in surgical admission volume, operative complexity, and comorbidity burden before, during, and after the pandemic at a Romanian tertiary maxillofacial center. Methods: This retrospective mixed-methods study included 248 admissions for oral and oropharyngeal SCC between 2018 and 2024. A structured administrative database was deterministically linked to narrative discharge summaries. Admissions were grouped into pre-pandemic (n = 117), pandemic (n = 93), and post-pandemic (n = 38) periods. Statistical analyses included between-period comparisons, segmented interrupted time-series analysis, and multivariable logistic regression. Qualitative thematic analysis was used to contextualize surgical and perioperative complexity. Results: Mean monthly admissions decreased from 4.9 before the pandemic to 2.6 during the pandemic and 1.6 in the post-pandemic period. Interrupted time-series analysis identified a significant declining baseline monthly trend (IRR 0.973, 95% CI 0.950–0.996; p = 0.024), without a significant immediate level change or post-onset slope change. Neck dissection increased from 23.9% before the pandemic to 39.8% during the pandemic (p = 0.045) and was independently associated with the pandemic/post-pandemic period (adjusted OR 1.87, 95% CI 1.06–3.29; p = 0.030). Qualitative findings identified recurrent codes related to surgical complexity, reconstruction, extensive nodal surgery, comorbidity burden, and perioperative management. Conclusions: Oral and oropharyngeal SCC surgical admissions showed a significant declining baseline trend between 2018 and 2024, while patients treated during and after the pandemic had higher adjusted odds of undergoing neck dissection. The findings support sustained oncological surveillance, timely referral, and multidisciplinary perioperative planning. Further multicenter studies incorporating standardized tumor–node–metastasis (TNM) staging and human papillomavirus (HPV) documentation are required to confirm these observations.
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Background/Objectives: This study evaluated changes in routine adult vaccination across the COVID-19 pandemic period in Istanbul primary care using interrupted time series (ITS) analysis, disentangling immediate from gradual effects and comparing patterns across socioeconomically distinct centers, through a multicenter retrospective analysis of routine
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Background/Objectives: This study evaluated changes in routine adult vaccination across the COVID-19 pandemic period in Istanbul primary care using interrupted time series (ITS) analysis, disentangling immediate from gradual effects and comparing patterns across socioeconomically distinct centers, through a multicenter retrospective analysis of routine (non-COVID-19 vaccination records). Methods: The full descriptive dataset comprised 33,016 adult vaccination records. After excluding 25,805 COVID-19 vaccination records, 7211 routine (non-COVID-19) vaccination records from nine family medicine units in three Istanbul training family health centers—Şişli-Gülbahar, Kağıthane, and Gaziosmanpaşa—were included in the routine vaccine and ITS analyses and were analyzed over 97 monthly observations (June 2017–August 2025), divided into three 672-working-day periods: pre-pandemic, pandemic, and post-pandemic. Segmented negative binomial ITS regression with a log (working days) offset was the primary analysis; Newey-West HAC-robust Poisson regression served as sensitivity analysis. Catchment districts were characterized using the 2022 Socioeconomic Development Ranking (SEGE-2022). Results: No significant immediate level change occurred in total routine vaccination at pandemic onset. Pneumococcal vaccination showed the most pronounced signal: an upward pretrend (annual slope IRR = 2.583; p = 0.001), a level increase at onset (IRR = 3.589; p = 0.013), then a rapid within-pandemic slope decline (annual slope IRR = 0.227; p < 0.001). Tetanus-diphtheria (Td) vaccination fell sharply at onset (IRR = 0.686; p = 0.002) and continued declining post-pandemic (annual slope IRR = 0.805; p = 0.008). Versus Gaziosmanpaşa (rank 85/973), Kağıthane (rank 38) showed the highest total routine vaccination rate (excluding COVID-19 vaccination) (IRR = 1.539; p < 0.001), exceeding Şişli (rank 1; IRR = 1.269; p < 0.001). Conclusions: Changes in routine adult vaccination across the pandemic period were vaccine-specific: pneumococcal vaccination surged then declined; Td vaccination showed continued post-pandemic decline. Center-level vaccination patterns were not consistently aligned with district-level socioeconomic ranking.
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Tom R. W. Tipton, Joseph A. Bore, Joseph Timothy, Stephanie Longet, Stephen M. Laidlaw, Grace Hood, Craig Thompson, Jack Mellors, Ifono Kekoura, Millimon S. Lucien, Beatrice K. Koivogui, Kpade Zeze, David Matthews, Andrew D. Davidson, Alex Mentzer, Donal Skelly, Paul Klenerman, Julian Hiscox, N’Faly Magassouba, Kimberley Fornace and Miles W. Carrolladd
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Objectives: The SARS-CoV-2 pandemic caused major morbidity, mortality, and economic disruption, highlighting the need to better understand zoonotic spillover risks posed by coronaviruses. We investigated whether archived human sera from forested Guinea contained evidence of prior exposure to coronaviruses antigenically related to
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Objectives: The SARS-CoV-2 pandemic caused major morbidity, mortality, and economic disruption, highlighting the need to better understand zoonotic spillover risks posed by coronaviruses. We investigated whether archived human sera from forested Guinea contained evidence of prior exposure to coronaviruses antigenically related to known pathogenic human coronaviruses. Methods: Archived sera collected in 2017–2018 from wildlife hunter communities in Guinea were analysed using serological assays against spike glycoproteins from SARS-CoV, SARS-CoV-2, MERS-CoV, and seasonal human coronaviruses. Binding responses to receptor binding domains were also assessed, together with spatial and subgroup analyses. Results: Pre-pandemic sera showed IgG cross-reactivity to SARS-CoV, SARS-CoV-2, and MERS-CoV spike antigens. A distinct subgroup demonstrated strong binding to both SARS-CoV and MERS-CoV receptor binding domains. Conclusions: These findings highlight the utility of sero-epidemiology in identifying potential zoonotic spillover. However, further investigation is needed to identify these viruses and determine their homology to known pathogenic coronaviruses.
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Lower respiratory tract infections (LRTIs) are a leading infectious cause of death in children worldwide. Complete blood count (CBC)-derived inflammatory ratios are low-cost and widely available, yet their reported performance varies. We reviewed 46 PubMed-indexed studies (2016–2026) in children aged 0–18 years with
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Lower respiratory tract infections (LRTIs) are a leading infectious cause of death in children worldwide. Complete blood count (CBC)-derived inflammatory ratios are low-cost and widely available, yet their reported performance varies. We reviewed 46 PubMed-indexed studies (2016–2026) in children aged 0–18 years with viral, bacterial, or mycobacterial LRTI. The findings were mapped across diagnosis, etiological differentiation, severity, and outcome prediction. The neutrophil-to-lymphocyte ratio (NLR) was the most investigated marker, with the broadest evidence base for severity assessment and for separating bacterial from viral disease, although its performance remained pathogen-, population-, and endpoint-dependent; it was elevated in severe pertussis, tuberculosis, Mycoplasma pneumoniae, Streptococcus pneumoniae, and SARS-CoV-2 infection, whereas findings in respiratory syncytial virus infection were conflicting. The platelet-to-lymphocyte ratio had the next broadest evidence base for severity, and the systemic immune-inflammation index was consistently elevated in Mycoplasma pneumoniae and SARS-CoV-2 infection. No single ratio performed consistently across all etiologies. Ratios governed by one dominant immunopathogenic mechanism behaved predictably; those whose numerator and denominator respond to the same process did not. Cut-offs were neither standardized, age-specific, nor externally validated, and most estimates derived from retrospective cohorts in few countries; reported values therefore represent association and discrimination rather than validated prediction. Standardized, age-specific thresholds are needed before these markers can support routine risk stratification.
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Laura G. Coelho, Lilian M. Diniz, Stella C. Galante, Cristiane S. Dias, Maria Christina L. Oliveira, Enrico A. Colosimo, Ana Cristina Simões e Silva, Fernanda N. Duelis, Maria Eduarda T. Bernardes, Julia O. Zavitoski, Daniella R. B. Martelli, Fabrício Emanuel S. Oliveira, Hercílio Martelli-Júnior, Adriano L. Santos, Robert H. Mak and Eduardo A. Oliveira
In the post-pandemic era, identifying children who are most susceptible to severe illness and COVID-19-related mortality is essential for guiding public health policies. This study examined the risk factors for COVID-19-related severe illness and mortality from 2023 to mid-2025. We conducted a population-based
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In the post-pandemic era, identifying children who are most susceptible to severe illness and COVID-19-related mortality is essential for guiding public health policies. This study examined the risk factors for COVID-19-related severe illness and mortality from 2023 to mid-2025. We conducted a population-based cohort study using nationwide Brazilian data from patients aged <18 years with laboratory-confirmed SARS-CoV-2 infection between January 2023 and June 2025. The primary outcomes were COVID-19-related severity and death. Separate binary multivariable logistic regression models were developed for each of the outcomes. Among 465,689 children, 1.3% (n = 5963) developed severe illness, and 0.18% (n = 847) died. Factors associated with an increased risk of severe illness included age < 2 years, presence of comorbidities, Indigenous ethnicity, and lack of vaccination. Neurological disorders conferred the highest risk among the clinical conditions (adjusted odds ratio [aOR] = 34.1; 95% CI: 27.9–41.8). Regional differences were also observed; the North and Northeast regions showed higher mortality (aOR = 2.3; 95% CI: 1.8–3.0) than the Central-West region. Compared with White ethnicity, non-White ethnicities had higher mortality: Indigenous (aOR = 23.5; 95% CI: 13.5–39.3), Black (aOR = 1.95; 95% CI: 1.29–2.92), and Brown (aOR = 1.43; 95% CI: 1.18–1.73) ethnicities. Lack of any vaccine dose was associated with a significantly increased risk of severe illness (aOR = 1.39; 95% CI: 1.15–1.67. p < 0.001) and death (aOR = 2.1; 95% CI: 1.3–3.5; p < 0.001). In the post-pandemic era, younger age, comorbidities, sociodemographic disparities, and lack of vaccination were associated with an increased risk of severe illness and COVID-19-related death in the pediatric population.
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The first webinar in the series, held on 17 April 2020, saw both Prof. Dr. Antoine Flahault, Director of the Institute of Global Health, University of Geneva, Switzerland, and Prof. Dr. Evelyne Bischof, Associate Professor, Shanghai University of Medicine and Health Sciences, Shanghai, China and Research physician, University Hospital of Basel, Basel, Switzerland speak on this topic.
The second webinar in the series, entitled “Coronaviruses: history, replication, innate immune antagonism”, saw Prof. Dr. Susan R. Weiss, Professor of Microbiology, Perelman School of Medicine, University of Pennsylvania speak on this topic.
WEBINAR 3: Could the COVID-19 Crisis be the Opportunity to Make Cities Carbon Neutral, Liveable and Healthy
The third webinar in this series was presented by Prof. Dr. Mark Nieuwenhuijsen, a world leading expert in environmental exposure assessment, epidemiology, and health risk/impact assessment with a strong focus and interest on healthy urban living.
WEBINAR 4: COVID-19 - Global Supply Chains and the SDGs
For the fourth webinar of this series, Prof. Dr. Max Bergman, Dr. Dorothea Schostok and Prof. Dr. Patrick Paul Walsh gave a presentation on Global Supply Chains and the SDGs.
WEBINAR 5: The New Role of Family Physicians in Times of COVID-19
The fifth webinar of the COVID-19 Series saw Prof. Dr. Christos Lionis discuss the new role of family physicians that emerged during the COVID-19 pandemic.
WEBINAR 6: Survey on Symptoms/Signs, Protective Measures, Level of Awareness and Perception Regarding COVID-19 Outbreak among Dentists
In the sixth webinar of this series, Prof. Dr. Guglielmo Campus and Prof. Dr. Maria Grazia present and discuss the risk and the preventions that can and should be taken by dentists during this pandemic.
WEBINAR 7: Living with COVID-19: An Early Intervention Therapeutic Strategy to Control the Pandemic
The seventh webinar of the COVID-19 series, Dr. Hamid Merchant discussed the different therapeutic strategies that can be adopted in the early stages of the infection.
WEBINAR 8: Impact of COVID-19 on Routine Immunization, Reproduction and Pregnancy Outcome
For the eighth COVID-19 webinar, Prof. Dr. Jon Øyvind Odland discussed the effect that COVID-19 seems to have on pregnant women; whereas Prof. Dr. Giovanni Gabutti discussed the role of routine immunization as a way of fighting COVID-19.
