Journal of Medical Virology

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...

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...

BackgroundHeartland virus (HRTV) is an emerging tick-borne virus capable of causing severe illness and death. The burden of disease is likely underestimated due to limited seroprevalence studies, lack of commercially available diagnostic tests, and an overlapping clinical syndrome with more commonly diagnosed bacterial diseases such as spotted fever group rickettsiosis or ehrlichiosis. MethodsActive surveillance for Heartland virus disease was conducted at a large academic center from March to ...

Strengthening in-country sequencing capacity generated 28 Lassa virus genomes from human clinical cases, expanding our knowledge of Lassa fever in Guinea. Phylogeographic analysis revealed cross-border exchange between Liberia and the NZerekore region, and a Sierra Leone introduction into the Gueckedou area. Enhanced genomic surveillance is crucial to guide future public health actions.

Syphilis remains a major public health concern. However, current serologic assays are limited in their ability to distinguish active from previously treated disease. We applied tandem mass tag-based quantitative proteomics to plasma from 10 adults with active syphilis and 10 age- and gender-matched non-diseased controls. We identified 54 differentially regulated proteins (36 upregulated, 18 downregulated). Those proteins map to immune and inflammatory responses, acute-phase signaling, coagulatio...

BackgroundCambodia has made great progress in reducing malaria transmission and is targeting elimination. While this progress is particularly marked for Plasmodium falciparum, the situation is different for Plasmodium vivax. It is generally assumed that symptomatic patients are effectively diagnosed using rapid diagnostic tests (RDTs), regardless of transmission intensity. MethodsIn 2023 we conducted a cross-sectional survey among 986 treatment-seeking patients in 6 provinces of Cambodia with v...

RIG-I is a cytosolic immune receptor that provides the first line of defense by detecting viral RNA and triggering antiviral responses. Its physiological role in humans remains unclear, as no patients with complete RIG-I deficiency have yet been reported. We identified a critically ill COVID-19 patient with severe RIG-I deficiency caused by heterozygous RIG-I G731R, a novel dominant loss-of-function variant. The G731R mutation in helicase motif VI disrupts the arginine finger, impairing the ATPa...

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...

BackgroundElimination of Plasmodium vivax is challenging due to its dormant liver stages (hypnozoites), which can reactivate weeks or months after the primary infection, causing relapses and ongoing transmission of the parasite. Despite these challenges, P. vivax clinical case numbers have declined over the past decade in Cambodia. We used parasite genotyping to assess whether the decline in case numbers was reflected in parasite diversity and relatedness as a proxy to transmission. MethodsGeno...

Linezolid is a critical last-resort antimicrobial for multidrug-resistant Enterococcus faecium, particularly against vancomycin-resistant lineages where therapeutic options are severely limited. While resistance has historically arisen through de novo chromosomal mutations, the global emergence of transferable resistance mechanisms threatens to render more infections untreatable. Here, we characterise a recent (2023-2024) hospital-associated outbreak of linezolid-resistant E. faecium in Queensla...

Serological surveillance is fundamental to infectious disease research and informed public-health decision making. Immunoassays used in the study of pathogen-specific immunity have historically relied on the collection of venous blood. While critical for many public-health applications, this sample collection method is invasive and resource intensive. The costs and logistical barriers associated with venous blood collection are exacerbated in resource-limited regions, and the shift to less invas...

From 2021 to 2025, MRSA emerged as a major multidrug-resistant pathogen in the study area. Among 545 S. aureus isolates, 67.2% were MRSA, disproportionately affecting children under five (26.5%) and males (55.5%). Case incidence more than doubled by 2025, suggesting rising transmission or resistance. Most isolates were hospital-associated (85.2%), predominantly from outpatients (88.5%), with middle ear discharge as the main source (67%). Gentamicin showed the highest susceptibility (72.1%), whil...

Understanding host susceptibility to Mycobacterium tuberculosis (Mtb) is critical for the development of new vaccines. Certain individuals "resist" becoming infected with Mtb despite intensive exposure; however, it is unknown whether there is a genetic basis for "resistance" to Mtb infection across populations. Here we conducted a genome-wide association study (GWAS) of resistance to Mtb infection by carefully characterizing exposure to TB patients among 4,058 close contacts in India, Brazil, an...

BackgroundCandidemia is a rare but life-threatening bloodstream infection that remains difficult to predict using conventional risk stratification approaches, highlighting the need for improved predictive strategies. As a result, empiric antifungal therapy is often delayed even in high-risk patients. MethodsWe developed a deep learning model (PyTorch_EHR) to predict 7-day candidemia risk by using electronic health record data from two large cohorts (Houston Methodist Hospital System [HMHS] and ...

Background: Schistosoma mansoni is a leading cause of hepatosplenic disease in sub-Saharan Africa. Yet, associations with current Schistosoma mansoni infections and hepatosplenic organometry remain unclear in the context of widespread mass drug administration and co-endemic infections. Methods: From January to February 2024, we conducted a community-based, cross-sectional study nested within the SchistoTrack cohort in three districts of Uganda. Liver and spleen dimensions were assessed via point...

Vaccination frequently elicits suboptimal immunogenicity in organ transplant recipients, particularly those on long-term immunosuppressive therapy, highlighting the need for improved understanding of immunosuppression mechanisms and optimized vaccination strategies. This study enrolled a cohort of 132 individuals and observed significantly lower antibody levels in kidney transplant recipients (KTRs) compared to non-transplant controls (non-KTRs). Antibody levels were inversely associated with bo...

BackgroundMycoplasma genitalium (MG) is an emerging sexually transmitted infection (STI) associated with pelvic inflammatory disease and tubal factor infertility. Its relationship with impaired fecundity remains unclear and is rarely examined in the context of co-seropositivity with other STIs. MethodsWe conducted a secondary analysis of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial, a prospective preconception cohort of women with proven fecundity and prior pregnancy loss....

Background The microbial aetiology of early childhood caries (ECC) in sub-Saharan African populations remains poorly characterised, with most studies focusing on conventional cariogenic pathogens like Streptococcus mutans. This study aimed to characterise the salivary microbial profile of children with ECC in urban Kano, northern Nigeria. Methods In this cross-sectional study of 162 children aged 3-5 years in urban Kano, unstimulated saliva samples were collected and analysed using standard bact...

ObjectiveCongenital syphilis remains a preventable cause of fetal and neonatal morbidity and mortality, despite the availability of inexpensive diagnostics and effective treatment. We aimed to evaluate the maternal and congenital syphilis burden at the Instituto Nacional Materno Perinatal, Perus national referral center for maternal and perinatal care. MethodsWe conducted a retrospective analysis of aggregated, de-identified surveillance data from January 2023 to December 2025. Maternal prevale...

Nipah virus (NiV) is a sporadic yet extremely deadly zoonotic pathogen, with reported case fatality rates of 40%-75% in impacted areas. Prolonged incubation, documented relapse, and delayed-onset encephalitis following apparent recovery indicate that NiV dynamics are influenced by intricate temporal processes. However, mechanistic contributions of these processes to epidemic persistence remain poorly understood. In this study, we develop and analyze a delay differential equation model for NiV tr...