Search Results (85)

Background: The COVID-19 pandemic has profoundly altered the clinical and microbiological landscape of respiratory tract infections (RTIs), potentially reshaping pathogen distribution and antimicrobial resistance (AMR) profiles across care settings. Objectives: The objective of this study was to assess temporal trends in respiratory bacterial pathogens, antimicrobial resistance, and polymicrobial infections across three pandemic phases—pre-COVID (2018–2019), COVID (2020–2022), and post-COVID (2022–2024)—in hospitalized and ambulatory patients. Methods: We retrospectively analyzed 1827 respiratory bacterial isolates (hospitalized patients, n = 1032; ambulatory patients, n = 795) collected at a tertiary care center in Northern Italy. Data were stratified by care setting, anatomical site, and pandemic phase. Species identification and susceptibility testing followed EUCAST guidelines. Statistical analysis included chi-square and Fisher’s exact tests. Results: In hospitalized patients, a significant increase in Pseudomonas aeruginosa (from 45.5% pre-COVID to 58.6% post-COVID, p < 0.0001) and Acinetobacter baumannii (from 1.2% to 11.1% during COVID, p < 0.0001) was observed, with 100% extensively drug-resistant (XDR) rates for A. baumannii during the pandemic. Conversely, Staphylococcus aureus significantly declined from 23.6% pre-COVID to 13.7% post-COVID (p = 0.0012). In ambulatory patients, polymicrobial infections peaked at 41.2% during COVID, frequently involving co-isolation of Candida spp. Notably, resistance to benzylpenicillin in Streptococcus pneumoniae reached 80% (4/5 isolates) in hospitalized patients during COVID, and carbapenem-resistant P. aeruginosa (CRPA) significantly increased post-pandemic in ambulatory patients (0% pre-COVID vs. 23.5% post-COVID, p = 0.0014). Conclusions: The pandemic markedly shifted respiratory pathogen dynamics and resistance profiles, with distinct trends observed in hospital and community settings. Persistent resistance phenotypes and frequent polymicrobial infections, particularly involving Candida spp. in outpatients, underscore the need for targeted surveillance and antimicrobial stewardship strategies. Full article

Background/Objectives: Mobile healthcare units (MHUs) comprise flexible, ambulatory healthcare teams that deliver community care services, particularly in underserved or remote areas. In Greece, MHUs were pivotal in epidemiological surveillance during the COVID-19 pandemic and are now evolving into a sustainable and integrated service for much-needed community-based healthcare. To support this expanded role, targeted, competency-based training is essential; however, this can pose challenges, especially in coordinating synchronous learning across geographically dispersed teams and in ensuring engagement using an online format. Methods: A nationwide, online training program was developed to improve the knowledge of the personnel members of the Hellenic National Public Health Organization’s MHUs. This program was structured focusing on four core themes: (i) prevention–health promotion; (ii) provision of care; (iii) social welfare and solidarity initiatives; and (iv) digital health skill enhancement. The program was implemented by the University of Crete’s Center for Training and Lifelong Learning from 16 January to 24 February 2025. A multidisciplinary team of 64 experts delivered 250 h of live and on-demand educational content, including health screenings, vaccination protocols, biomarker monitoring, chronic disease management, treatment adherence, organ donation awareness, counseling on social violence, and eHealth applications. Knowledge acquisition was assessed through a pre- and post-training multiple-choice test related to the core themes. Trainees’ and trainers’ qualitative feedback was evaluated using a 0–10 numerical rating scale (Likert-type). Results: A total of 873 MHU members participated in the study, including both healthcare professionals and administrative staff. The attendance rate was consistently above 90% on a daily basis. The average assessment score increased from 52.8% (pre-training) to 69.8% (post-training), indicating 17% knowledge acquisition. The paired t-test analysis demonstrated that this improvement was statistically significant (t = −8.52, p < 0.001), confirming the program’s effectiveness in enhancing knowledge. As part of the evaluation of qualitative feedback, the program was positively evaluated, with 75–80% of trainees rating key components such as content, structure, and trainer effectiveness as “Very Good” or “Excellent.” In addition, using a 0–10 scale, trainers rated the program relative to organization (9.4/10), content (8.8), and trainee engagement (8.9), confirming the program’s strength and scalability in primary care education. Conclusions: This initiative highlights the effectiveness of a structured, online training program in enhancing MHU knowledge, ensuring standardized, high-quality education that supports current primary healthcare needs. Future studies evaluating whether the increase in knowledge acquisition may also result in an improvement in the personnel’s competencies, and clinical practice will further contribute to assessing whether additional training programs may be helpful. Full article

(1) Background: The ongoing global health threat posed by SARS-CoV-2 requires reliable and accessible diagnostic tools, especially in resource-limited settings where RT-qPCR may be impractical. This study describes the development and validation of two enzyme-linked immunosorbent assays (ELISA) designed to detect anti-SARS-CoV-2 IgG antibodies employing recombinant S1 and S2 spike protein subunits. (2) Methods: The assays were optimized and validated using serum samples from 354 RT-qPCR-confirmed hospitalized patients and 337 pre-pandemic blood donors. (3) Results: The S1-based ELISA achieved a 52.8% sensitivity and a specificity of 93.5%, with an area under the ROC curve (AUC) of 71.6%. In contrast, the S2-based ELISA demonstrated superior diagnostic performance, with a sensitivity of 63.7%, a specificity of 99.7%, and an AUC of 83.1%. Cross-reactivity analysis using sera from individuals with unrelated infectious diseases confirmed the high specificity of the S2-ELISA. Time-stratified analysis revealed that sensitivity increased with time, peaking between 15 and 21 days post-symptom onset. Compared to commercial serological assays, the S2-ELISA demonstrated comparable or improved performance, particularly in specificity and diagnostic odds ratio. (4) Conclusions: The S2-ELISA offers a robust, highly specific, and operationally simple tool for serological detection of SARS-CoV-2 infection. Its strong diagnostic performance and accessibility make it well-suited for implementation in diverse epidemiological settings, particularly where molecular testing is limited. The development of affordable, validated serological assays such as this is critical for strengthening surveillance, understanding transmission dynamics, and informing public health responses. Full article

Community-based serosurveillance for emerging zoonotic viruses can provide a powerful and cost-effective measurement of cryptic spillovers. Betacoronaviruses, including SARS-CoV, SARS-CoV-2 and MERS-CoV, are known to infect bats and can cause severe respiratory illness in humans, yet remain under-surveyed in high-risk populations. This study aimed to determine the seroprevalence of betacoronaviruses in an occupational cohort in contact with bats before and after the emergence of SARS-CoV-2. Serum samples from pre- and post-COVID-19 pandemic were screened using antigen-based multiplex microsphere immunoassays (MMIAs) and a multiplex surrogate virus neutralization test (sVNT). Pre-pandemic samples showed no SARS-CoV-2 antibodies, while post-pandemic samples from vaccinated participants displayed binding and neutralizing antibodies against SARS-CoV-2 and a related bat CoV. Furthermore, one participant (1/237, 0.43%) had persistent antibodies against MERS-CoV in 2017, 2018 and 2021 but was seronegative in 2023, despite reporting no history of traveling abroad or severe pneumonia. The observed sustained antibody levels indicate a possible exposure to MERS-CoV or a MERS-CoV-like virus, although the etiology and clinical relevance of this finding remains unclear. Ongoing surveillance in high-risk populations remains crucial for understanding virus epidemiology and mitigating zoonotic transmission risk. Full article

The SARS-CoV-2 pandemic and the implementation of associated non-pharmaceutical interventions (NPIs) profoundly altered the epidemiology of seasonal influenza viruses. To investigate these changes, we analyzed influenza-like illness samples in Shenzhen, China, across six influenza seasons spanning 2018 to 2024. Influenza activity declined markedly during the SARS-CoV-2 pandemic compared with the pre-pandemic period but returned to or even exceeded pre-pandemic levels in the post-pandemic era. Phylogenetic analysis of hemagglutinin (HA) and neuraminidase (NA) genes from 58 H1N1pdm09, 78 H3N2, and 97 B/Victoria isolates revealed substantial genetic divergence from the WHO-recommended vaccine strains. Notably, key mutations in the HA genes of H1N1pdm09, H3N2, and B/Victoria viruses were concentrated in the receptor-binding site (RBS) and adjacent antigenic sites. Hemagglutination inhibition (HI) assays demonstrated that most circulating viruses remained antigenically matched to their corresponding vaccine strains. However, significant antigenic drift was observed in H3N2 clade 3C.2a1b.1b viruses during the 2018–2019 season and in B/Victoria clade V1A.3a.2 viruses during the 2023–2024 season. These findings highlight the impact of NPIs and pandemic-related disruptions on influenza virus circulation and evolution, providing critical insights for future surveillance and public health preparedness. Full article

Objective: This systematic review and meta-analysis aims to evaluate the temporal changes in Helicobacter pylori antibiotic resistance in Russia based on studies published over the past 15 years. Materials and Methods: We conducted a comprehensive literature search in MEDLINE/PubMed, EMBASE, the Russian Science Citation Index, and Google Scholar, following the PRISMA 2020 guidelines. Our meta-analysis was pre-registered in PROSPERO (CRD 420251025636). The inclusion criteria included original research, published in English or Russian in 2011–2024, involving antibiotic susceptibility testing in treatment-naive Russian adults using validated diagnostic methods. Two independent researchers selected studies and extracted data using standardized procedures, with methodological quality assessed via the Newcastle–Ottawa Scale. Pooled resistance rates were calculated using fixed/random-effects models in MedCalc 23.1.5 and Python 3.9.21, with meta-regression investigating temporal trends and subgroup analyses examining regional and methodological variations. Results: We identified 16 studies comprising 1206 H. pylori isolates. The pooled analysis of studies (2011–2025) revealed an overall clarithromycin resistance rate of 15.236%, with a significant temporal increase from 11.903% pre-2015 to 21.024% in 2020–2024 (p = 0.0049). Metronidazole showed consistently high pooled resistance (33.309%), while amoxicillin (1.828%), levofloxacin (19.014%), tetracycline (1.328%), and rifampicin (5.803%) maintained low resistance rates, and dual clarithromycin–metronidazole resistance was observed in 2.793% of isolates. Regional disparities were notable in the two largest cities of Russia, with 18.763% clarithromycin resistance in Moscow versus 28.540% in Saint-Petersburg. Conclusions: Russia surpasses the Maastricht VI Consensus resistance threshold for clarithromycin (15%), necessitating revision of empirical treatment strategies. The significant increase in clarithromycin resistance, potentially exacerbated by antibiotic use during the COVID-19 pandemic, underscores the urgent need for resistance-guided therapies and ongoing national surveillance programs to optimize H. pylori management. Full article

Background: Acinetobacter baumannii is a significant pathogen and a major contributor to healthcare-associated infections, particularly in intensive care units. Its high potential for developing multiple drug resistance (MDR) makes it a challenging pathogen to manage. This study investigates the prevalence and resistance patterns of MDR A. baumannii isolates over a six-year period at a university hospital in Southern Italy. Objective: The aims of this study are to evaluate recent trends in the prevalence of MDR A. baumannii, analyze resistance patterns, and assess the impact of the antimicrobial diagnostic stewardship program implemented in 2018. Methods: This retrospective cohort study was conducted at the University Hospital of Campania “Luigi Vanvitelli” from 2018 to 2023. A total of 191 A. baumannii isolates from blood, urine, and wound samples were analyzed. Antimicrobial susceptibility testing was performed following EUCAST guidelines. The prevalence of MDR strains was assessed across three periods: pre-pandemic (2018–2019), during the pandemic (2020–2021), and post-pandemic (2022–2023) Results: Among the 191 isolates, 89.5% were classified as MDR. The highest number of isolates occurred in 2020, with blood cultures and urine samples increasing by 40.9% and 62.5%, respectively, while wound isolates decreased by 34.2%. The implementation of antimicrobial diagnostic stewardship programs correlated with a reduction in carbapenem resistance in 2020 and 2022. However, resistance to meropenem and colistin persisted. A 60.4% decline in total isolation from 2020 to 2023 suggests effective infection control measures. Conclusions: MDR A. baumannii remains a significant threat to healthcare. Although there have been slight reductions in resistance following antimicrobial stewardship interventions, persistent resistance to last-line antibiotics underscores the urgent need for alternative treatments, enhanced surveillance, and stricter infection control strategies. Full article

Enterovirus D68 (EV-D68) caused large biennial cyclical outbreaks of respiratory disease and cases of acute flaccid myelitis from 2014 to 2018 in the USA. An anticipated outbreak did not occur in 2020, likely due to non-pharmaceutical interventions targeting the COVID-19 pandemic. A large respiratory disease outbreak occurred again in 2022, but uncertainty remained regarding if circulation of EV-D68 would return to the pre-pandemic patterns. We conducted prospective active surveillance of clinical respiratory specimens from Colorado children for EV-D68 in 2023 and 2024. A subset of residual specimens positive for rhinovirus/enterovirus (RV/EV) were tested for EV-D68 via a validated in-house EV-D68 reverse transcription–PCR assay. During epi weeks 18–44 in 2023, 525 residual specimens positive for RV/EV all tested negative for EV-D68. In 2024, during epi weeks 18–44, 10 (1.8%) of the 546 RV/EV-positive specimens were EV-D68-positive. The EV-D68-positive cases were predominantly young children (median age 4.8 years) receiving treatment with asthma medications. Following the 2022 EV-D68 outbreak, an anticipated outbreak did not occur in 2023. While EV-D68 was detected in 2024, the number of cases was not as significant as in prior outbreak years. Continued surveillance for EV-D68 will be important to understand the future dynamics of EV-D68 circulation and prepare for future outbreaks. Full article

Background: The aim of this study was to evaluate the usefulness of close clinical surveillance intervals combined with oral brush biopsies to enable the early detection of malignant transformations in patients with oral lichen planus (OLP) performed in our oral medicine clinic. Methods: This retrospective study was carried out on 414 patients suffering from OLP, based on pre-established clinical and histopathological criteria, who received long-term follow-up between 1993–2022 (ranging from 6 months to 22.2 years). Results: A total of 297 patients were included in this study. Four people developed an oral squamous cell carcinoma (OSCC) during the observation period. Patients with close follow-up intervals were detected at early stages (two cases showed histologically SIN III and one patient was classified as having a pT1N0M0 tumour). One case was dropped in the consultation hour during the COVID19 pandemic and appeared again two years later, staged as a pT3N1M0 tumour based on an OLP. Three of the cases were clinically doubtful, which led to brush biopsies. Afterwards, additional DNA-image cytometry was performed, in which all the specimens of brush biopsies showed aneuploidy as a marker for malignancy, regarding both stem line and single cell aneuploidy. Conclusions: A careful surveillance programme consisting of check-ups every 3–4 months, oral brush biopsies, and static DNA image cytometry in cytologically diagnosed doubtful or suspicious cases assures the early detection of malignant transformation in the cancer’s early intraepithelial and microinvasive stages. Full article

Background/Objectives: Urinary tract infections (UTIs) represent a significant public health challenge, with Escherichia coli being the primary causative pathogen. The rise in antimicrobial resistance (AMR), further intensified by shifts in antibiotic prescribing practices during and after the COVID-19 pandemic, poses substantial difficulties in treatment optimization and clinical management. Methods: This retrospective study analyzed 644 E. coli strains from urine samples collected in a southeastern Romanian hospital during two periods: pre-pandemic (2018–2019, N = 361) and post-pandemic (2023–2024, N = 283). Antimicrobial susceptibility was assessed using the VITEK automated system for key antibiotic classes. Results: A significant increase in fluoroquinolone resistance was observed, especially for ciprofloxacin (p = 0.02), alongside rising ceftriaxone resistance (p = 0.004), suggesting the spread of ESBL-producing strains. Resistance to trimethoprim/sulfamethoxazole, ampicillin, and amoxicillin/clavulanic acid remained high, limiting their empirical use. Carbapenem resistance was low (p > 0.1), while nitrofurantoin and fosfomycin retained high efficacy (p = 0.26 and p = 0.64). Conclusions: The post-pandemic period showed a concerning rise in resistance to fluoroquinolones and third-generation cephalosporins, highlighting the need for stricter antimicrobial stewardship. Carbapenems remain effective for severe infections, while nitrofurantoin and fosfomycin are reliable first-line options for uncomplicated UTIs. Continuous AMR surveillance is essential to optimize treatment and curb multidrug-resistant strains. Full article

The COVID-19 pandemic imposed a substantial burden on healthcare systems worldwide, yet reliable data on COVID-19 morbidity, mortality, and healthcare costs in Latin America remain limited. This study explored the disease and economic burden of COVID-19 in Argentina, Brazil, Chile, Colombia, Mexico, and Peru during the pre-vaccination period. Using national databases and a systematic review of the literature, we analyzed data on adults aged 18 and older, reporting cases, death rates, years of life lost, excess mortality, and direct medical costs. Before vaccination programs began, the average COVID-19 incidence rate was 6741 per 100,000 adults. Of these, 91% were mild cases, 7% moderate/severe, and 2% critical. Among 2,201,816 hospitalizations, 27.8% required intensive care, and 17.5% required mechanical ventilation. Excess mortality ranged from 76 to 557 per 100,000, and years of life lost spanned 241,089 to 3,312,346. Direct medical costs ranged from USD 258 million to USD 10,437 million, representing 2–5% of national health expenditures. The findings highlight significant variability across countries and provide crucial insights to help policymakers to make informed decisions and allocate resources effectively to improve national strategies around surveillance, preventive and treatment strategies to control the spread of COVID-19 disease in the future. Full article

Human parvovirus B19 (B19V) follows a well-documented cyclical epidemiology, with peaks occurring every 3–4 years. However, recent reports indicate an unusual resurgence in B19V infections across multiple countries, prompting increased surveillance. This study analyzed molecular diagnostic assay results from 826 unique-patient samples tested for B19V DNA between 2019 and 2024 at a large Italian tertiary-care hospital, covering pre-, during, and post-COVID-19 years. Overall, 80 of 826 patients (9.7%) tested positive for B19V DNA. A significant increase in positivity was observed in 2024 (23.4%), with a peak in May, representing an eightfold rise compared to 2019–2020. Despite this surge, the distribution of positive cases across population categories remained consistent with previous years, with 32 of 80 (40.0%) positive samples from pregnant women and 27 of 80 (33.8%) from hematology/oncology patients. Among 66 B19V DNA-positive patients with available serology, 4 of 66 (6.1%)—all immunocompromised—lacked detectable IgM/IgG despite high B19V DNA levels (7.8 log₁₀ IU/mL). These findings highlight the importance of integrating molecular and serological diagnostics, particularly in high-risk populations. Given the potential impact of the COVID-19 pandemic on B19V circulation, continued surveillance is essential to determine whether this resurgence represents a temporary fluctuation or a sustained epidemiological shift. Full article

Background: Antimicrobial consumption (AMC) patterns, besides prescribing behaviors, reflect the changing epidemiology of infectious diseases. Routine surveillance data have been used to investigate the development of AMC from 2017 to 2023 and the impact of COVID-19 within the context of the framing time periods. Methods: Data from 112 hospitals, continuously participating from 2017 to 2023 in the national surveillance system of hospital antimicrobial consumption based at the Robert Koch Institute, were analyzed according to the WHO ATC (Anatomical Therapeutic Chemical)/DDD (Defined Daily Dose) method and categorized according to the WHO AWaRe-classification. AMC was quantified by consumption density (CD) expressed in DDD/100 patient days (PD) and DDD/100 admissions (AD). The time period was subdivided into three phases: pre-pandemic phase (2017–2019), main pandemic phase (2020–2021) and transition phase (2022–2023). Linear regression models have been used to determine the presence of an overall trend, the change in intra-phasic trends and phase-specific mean consumption levels over time. Results: From 2017 to 2023 total antibiotic consumption decreased by 7% from 57.1 to 52.9 DDD/100 PD. Four main kinetic patterns emerged across different antibiotic classes: Pattern 1 displays a decreasing pre-pandemic trend, which slowed down throughout the pandemic and transition phase and was exhibited by second-generation cephalosporins and fluoroquinolones. Pattern 2 reveals a rising pre-pandemic trend, which decelerated in the pandemic phase and accelerated again in the transition phase and was expressed by aminopenicillins/beta-lactamase inhibitors, beta-lactamase sensitive pencillins, azithromycin and first-generation cephalosporins. Pattern 3 shows elevated mean consumption levels in the pandemic phase exhibited by carbapenems, glycopeptides, linezolid and third-generation cephalosporins. Pattern 4 reveals a rising trend throughout the pre-pandemic and pandemic phase, which reversed in the transition phase without achieving pre-pandemic levels and was expressed by beta-lactamase resistant penicillins, daptomycin, fosfomycin (parenteral) and ceftazidime/avibactam. Conclusions: Kinetic consumption patterns across different antibiotic classes might reflect COVID-19-related effects and associated changes in the epidemiology of co-circulating pathogens and health care supply. Broad-spectrum antibiotics with persisting elevated consumption levels throughout the transition phase require special attention and focused antimicrobial stewardship activities. Full article

Background: The rise in multidrug-resistant (MDR) Gram-negative bacteria (GNB) poses a critical threat to global health, exacerbated by the increased use of antibiotics during the SARS-CoV-2 pandemic. Colistin, often considered a last-resort antibiotic, has seen heightened usage, raising concerns about resistance and clinical outcomes. This study investigates the evolution of colistin resistance in GNB during the SARS-CoV-2 pandemic, with a focus on clinical outcomes in colistin-treated patients. Methods: Conducted in “Saint Spiridon” Hospital, Iasi, Romania, the study assesses antibiotic usage, trend in GNB resistance to colistin, and mortality rates across distinct pandemic phases (pre-pandemic, Delta, Omicron, and post-pandemic). A retrospective longitudinal analysis spanning 2011 to 2023 was performed. Statistical models were employed to analyze mortality risk and assess the pandemic’s impact on antimicrobial dynamics. Results: Colistin usage increased significantly during the pandemic, with the highest doses recorded during the Omicron phase. Resistance to colistin, particularly among A. baumannii and K. pneumoniae, was associated with increased mortality rates. The statistical model demonstrated robust predictive accuracy for mortality across the pandemic phases, with an AUC of 0.866 in the post-pandemic period. The findings underscore the critical role of A. baumannii as a driver of adverse outcomes, with co-infections significantly linked to systemic infections and higher mortality. Conclusions: The study highlights the evolving trends in colistin therapy and resistance, emphasizing the pandemic’s impact on antimicrobial stewardship and the persistent challenges posed by MDR pathogens. We emphasize the need for antimicrobial resistance surveillance, including the monitoring of colistin resistance, which is considered a last-resort antibiotic. Full article

Background. Influenza remains a significant public health issue, with seasonal trends varying across regions. This study provides a comprehensive analysis of influenza virus trends in Italy, leveraging epidemiological and virological data from the Istituto Superiore di Sanità (ISS). The primary objective is to assess influenza activity at both national and regional levels, highlighting variations in incidence rates and viral subtype circulation during the 2023/2024 season. Methods. We conducted a systematic approach to data collection, processing, and visualization, utilizing influenza surveillance data from ISS. Incidence rates, subtype distribution, and co-circulating respiratory viruses were analyzed to identify key trends. Results. Our findings reveal a significant increase in influenza cases during the 2023/2024 season, with incidence rates surpassing pre-pandemic levels. Notably, changes in the circulation of influenza A(H3N2) and influenza B were observed, alongside the presence of other respiratory viruses such as RSV and rhinovirus. Conclusions. This study underscores the importance of real-time surveillance, transparent data sharing, and advanced visualization tools in guiding public health responses. By integrating lessons from COVID-19, we highlight the necessity of standardized surveillance frameworks to enhance preparedness for future seasonal outbreaks and potential pandemics. Full article