Clinical Microbiology and Infection

The emergence of vaccine covered serotypes causing invasive pneumococcal disease (IPD) is a serious concern worldwide. We investigated the unexpected rise of serotype 4 causing IPD primarily in non-vaccinated young adults after the COVID-19 pandemic that further spread to adults [≥] 65 years in recent years. For this purpose, we conducted a retrospective study of serotype 4 IPD cases (n=827) reported in Spain between 2009 and 2024. Whole-genome sequencing was performed to assess clonal lineag...

BackgroundThe epidemiology of suspected pediatric meningoencephalitis has shifted in the era of conjugate vaccines and multiplex PCR diagnostics, with viral pathogens now predominating over bacterial causes. Updated epidemiologic data are essential to adapt diagnostic and therapeutic algorithms to current clinical practice. MethodsThis retrospective single-center study included children and adolescents <18 years who underwent lumbar puncture with cerebrospinal fluid multiplex PCR for suspected ...

BackgroundHospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP), particularly those caused by multi-drug resistant organisms (MDROs), often require newer antibiotic treatment. The efficacy and safety of newer antibiotics compared to generic antibiotics in randomized controlled trials (RCTs) have not been evaluated before. MethodsIn this systematic review, we searched RCTs in the United States National Library of Medicine (PubMed), Cochrane Central Reg...

ObjectivesDiagnosis of community-acquired Legionnaires disease (CALD) relies on microbiological testing. Routine testing in hospitalised CAP patients has low positivity rates. We externally validated a Legionella prediction score, assessed its applicability in routine care, and explored potential updates. MethodsWe analysed data from 196 CALD patients from 20 Swiss hospitals and 196 Legionella-negative CAP controls matched by date of diagnosis ({+/-}14 days; August 2022-March 2024). We assessed...

This exploratory analysis of PAX LC, a Phase 2, 1:1 randomized, double-blind, superiority, placebo-controlled trial examined whether treatment with nirmatrelvir/ritonavir (NMV/r) versus placebo/ritonavir (PBO/r) in individuals with Long COVID could reveal immune features associated with symptom improvement. Eighty-two participants (n=45 PBO/r; n=37 NMV/r) provided blood samples at baseline (Day 0) and post-treatment (Day 28). Baseline demographic and immunological phenotypes were similar in the ...

BackgroundReliable identification of early predictors of adverse outcomes was essential during the pre-vaccination phase of the COVID-19 pandemic. Few studies have comprehensively integrated clinical presentation, laboratory parameters including arterial blood gas analysis, and chest computed tomography (CT) findings within a single well-characterized cohort, particularly in underrepresented regions of Brazil. MethodsThis retrospective cohort study included 482 consecutive adults (median age 61...

BackgroundRespiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in children, often leading to hospitalisation in infants. In low-resource settings where routine RSV diagnostics are unavailable, clinical overlap with bacterial pneumonia frequently results in unnecessary antibiotic use, contributing to antimicrobial resistance. ObjectiveTo evaluate the frequency and clinical determinants of antibiotic use among RSV-positive children under two years at a tertiary...

ImportanceRecent reports have highlighted an intense influenza activity related to the circulation of the influenza A(H3N2) subclade k variant. There is no data available on the impact of the emergence of H3N2 subclade k on the severity of the 2025-2026 epidemic or on the clinical phenotype of patients requiring admission to the intensive care unit (ICU). ObjectiveTo compare the clinical presentation, hospital mortality and virological characteristics of patients with laboratory-confirmed influ...

BackgroundPreoperative biliary stenting alters biliary colonization and may reduce the effectiveness of perioperative antibiotic prophylaxis in pancreatoduodenectomy. Although broader-spectrum regimens have been associated with improved infectious outcomes, their microbiological adequacy in routine clinical practice remains poorly defined. We therefore evaluated the real-world adequacy of a prolonged ampicillin-sulbactam protocol, its association with infectious outcomes and survival, and the po...

ObjectivesTo quantify how urine sample type and polymicrobial context impact antimicrobial resistance (AMR) in urinary tract infections (UTIs), using routine diagnostics at scale. MethodsIn this retrospective, single-centre study, we analysed 188,687 urine cultures from the Institute of Medical Microbiology, University of Zurich, Switzerland (January 2015 to May 2023). We compared midstream urine (MU), indwelling catheter (IDC), and intermittent catheter (IMC) samples. Samples were classified a...

ObjectiveTo quantify the seasonal burden of acute respiratory viral infections among healthcare workers (HCWs), characterize virologic etiologies, and identify predictors of symptomatic illness and sick leave. MethodsWe conducted a prospective cohort study of HCWs during winter 2024-2025, with weekly surveys capturing acute respiratory infections (ARI) and sick leave. Nasal-throat multiplex PCR swabs were self-collected during symptomatic episodes. Incidence rate ratios (IRRs) for symptomatic e...

RationaleObstructive sleep apnea (OSA) is linked to cardiovascular, metabolic, and cognitive morbidity. Although COVID-19 has been associated with long-term respiratory and neurological sequelae, its role in precipitating new-onset OSA remains unclear. ObjectivesTo evaluate whether SARS-CoV-2 infection increases risk of developing OSA up to 4.5 years post-infection and how risk varies by hospitalization status, demographics, comorbidities, and vaccination status. MethodsThis retrospective coho...

A number of vaccines and long-acting monoclonal antibodies have been shown to be effective in the prevention of respiratory syncytial virus (RSV) disease. However, an immune correlate of protection for RSV has not yet been identified. We conducted a systematic review to identify published reports of immunogenicity and/or efficacy in vaccines and long-acting monoclonal antibodies against RSV and performed a meta-analysis on extracted data to identify any relationship between antibody increase and...

Sepsis caused by drug-resistant pathogens remains a major contributor to under-five mortality in low- and middle-income countries, threatening progress toward Sustainable Development Goal (SDG) 3.2. Blood culture, the gold standard for sepsis diagnosis and antimicrobial stewardship, remains underutilised in routine pediatric care. This study assessed the extent and determinants of blood culture utilisation among hospitalised children under five years with suspected sepsis at four antimicrobial r...

BackgroundDiarrheal disease is the second leading cause of under-five mortality and morbidity in Sub-Saharan Africa. The World Health Organization (WHO) has developed treatment guidelines to support clinicians in the management of pediatric diarrhea; however, adherence to, and the impact of, these guidelines are not well described in low- and middle-income countries. MethodWe conducted a secondary analysis of data from the Enterics for Global Health study to determine whether adherence to WHO d...

PuhrposeTo evaluate the short- and long-term cross-sectional associations between COVID-19 infection and multidimensional sleep health. MethodsData from the COVID-19 Outbreak Public Evaluation (COPE) initiative were used to examine the association between a novel multidimensional sleep health measure (COPE Multidimensional Sleep Health Scale, CMSHS) modeled from the RuSATED instrument and (1) COVID-19 infection and (2) post-acute sequelae of SARS-CoV-2 infection (PASC). ResultsData from 11,326...

The rapid diagnosis of Campylobacter infections is important for the management of infectious gastroenteritis. Although stool culture is considered the gold standard, its sensitivity is limited and it requires prolonged incubation times. We performed a prospective multicenter study at nine healthcare facilities in Japan to evaluate a Campylobacter rapid antigen test using stool specimens between March 2024 and August 2025. Patients with suspected infectious gastroenteritis were consecutively enr...

BACKGROUNDDiagnostic performance of tongue swab Mycobacterium tuberculosis PCR has been evaluated for facility-based triage of symptomatic tuberculosis (TB). It is unknown whether tongue swab performance differs for detection of asymptomatic TB in community-based screening. METHODSTongue swabs were collected from adult household contacts of TB patients (HHC Cohort), and symptomatic adults presenting to clinics with presumptive TB (Clinic Cohort), at eight South African sites. TB Cases were defi...

BackgroundSevere Fever with Thrombocytopenia Syndrome (SFTS) is an acute infectious disease with high mortality. This study aimed to develop a quantitative scoring system for grading SFTS severity using dynamic clinical data. MethodsA retrospective study included 547 confirmed SFTS patients from two hospitals. Clinical data were collected over a 14-day course (divided into four phases). Patients were grouped into survivors (n=451) and non-survivors (n=96). Statistical analyses, including Kaplan...

BackgroundThere is a need for synthetic peptide-based serologic assays that exploit avidity to replace whole antigens while enabling low-cost diagnostics in resource-limited settings. ObjectiveTo evaluate the diagnostic accuracy of a polymeric peptide-based ELISA leveraging avidity to enhance signal. MethodA 15-member SARS-CoV-2 peptide library corresponding to multiple epitope clusters and proteins was screened by indirect ELISA using pooled sera from RT-PCR-confirmed COVID-19 patients to ide...