Evaluation of colonization factors of ETEC isolated from diarrheal patients in Bangladesh: A comparative approach using multiplex PCR and dot blot immunoassay.

Enterotoxigenic Escherichia coli (ETEC) harbors colonization factors (CFs) to colonize the small intestine. In this study, as part of routine systematic ETEC surveillance in Bangladesh, we evaluated CFs from ETEC isolated from hospitalized diarrheal patients using a multiplex PCR assay for the first time, as the availability of the monoclonal antibodies for dot blot assay became limited. A total of 5914 diarrheal patients were enrolled during the study period (2023-2024), and a PCR assay, targeting heat-labile toxin (LT) and heat-stable toxin (ST), found 531 ETEC-infected patients.

Clinical and environmental wastewater-based bacteriophage surveillance for high-impact diarrheal diseases, including cholera, in Bangladesh.

Bacteriophages (phages) likely play a critical role in modulating transmission dynamics of diarrheal pathogens. This study investigated the role of phages in modulating the prevalence and seasonal patterns of major diarrheal pathogens, O1 (VCO1), enterotoxigenic (ETEC), spp., and spp.

An O-Specific Polysaccharide Shigella flexneri 3a Conjugate Vaccine is Immunogenic and Protective against Virulent Keratoconjunctival Challenge in Guinea Pigs.

Shigella infection is a major cause of diarrhea, cognitive and physical stunting, and death in young children in resource-limited settings. A vaccine that is protective against shigellosis is needed. Immune responses that target the O-specific polysaccharide (OSP) of Shigella spp.

Epidemiological and Clinical Features of Enterotoxigenic (ETEC) Diarrhea in an Urban Slum in Dhaka, Bangladesh.

Background: Enterotoxigenic (ETEC) is a major cause of diarrheal illness, and population-based data on the incidence of clinically significant ETEC diarrhea in developing countries are limited. We provide insight into ETEC epidemiology; we followed a population-based cohort in a vaccine trial.

Methods: We analyzed data from a cluster-randomized controlled trial of an oral cholera vaccine conducted in an urban slum in Dhaka, Bangladesh.

Rapid tests as a practical alternative to slide agglutination for the confirmation of O1.

Slide agglutination for serogroup and/or serotype identification is a crucial step for confirming cholera by culture. Rapid diagnostic tests (RDTs) are typically used directly on stool but are not considered sufficient for cholera confirmation. However, they may provide a practical alternative to the slide agglutination step of culture as they are easy to use, store, and require minimal training.

Spike specific IgG3 and nucleocapsid IgG response in serum serve as distinguishing immunological markers between SARS-CoV-2 infection and vaccination.

Background: Both SARS-CoV-2 infection and COVID-19 vaccines elicit immunological responses. However, it is difficult to distinguish responses generated after vaccination versus natural infection.

Methods: We investigated SARS-CoV-2 spike receptor-binding domain (RBD) and nucleocapsid-specific IgG and RBD specific IgG subclasses (IgG1, IgG2, IgG3 and IgG4) responses using ELISA in four different groups; (1) COVID-19 patients (n=39) with varying disease severity and (2) COVID-19 vaccinated individuals (n=24, both adenovirus/mRNA based) (3) vaccinated after infection (n=39) and (4) patients experienced breakthrough infection (n=14), in Bangladesh.

Physicians' Perspectives Regarding Informal Health Practitioners in Bangladesh.

Rural Bangladesh faces challenges of limited health care resources and a shortage of health care professionals. Informal providers, particularly village doctors, fill this void by being a first point of care and a bridge to the formal health care system. This study explores formally trained physicians' perspectives on village doctors' role in the health care system.

Shigellosis in an Urban Slum in Kenya: Risk Factors and Antimicrobial Resistance.

Background: spp are among the notable causes of global diarrheal disease and death, accounting for 13.2% of deaths in 2016. Antimicrobial resistance complicates shigellosis management.

Evaluation of oral cholera vaccine (Euvichol-Plus) effectiveness against in Bangladesh: an interim analysis.

Introduction: Millions of Euvichol-Plus doses have been deployed from the global oral cholera vaccine stockpile in over 20 cholera-affected countries. However, information on Euvichol-Plus's effectiveness is limited. Using this vaccine in a cholera epidemic in Dhaka, Bangladesh, provided the opportunity to evaluate the vaccine effectiveness (VE) using a test-negative design.

Evaluation of naturally occurring IgG anti-Vi antibody titers as predictors and correlates of typhoid fever in Dhaka, Bangladesh.

Background: When delivered through vaccination Vi-polysaccharide antigen of Salmonella enterica serotype Typhi protects against typhoid by inducing IgG anti-Vi antibodies. We aimed to determine whether the presence of antibodies following natural infection is associated with a lower incidence of typhoid fever in endemic regions.

Methods: We analyzed data from a cohort study of typhoid fever conducted in Dhaka, Bangladesh.

Protection by natural cholera against later episodes of cholera over 10 years of follow-up in Matlab, Bangladesh: a retrospective cohort study.

Background: Patients with cholera have been shown to be protected against subsequent cholera for 3 years after their initial episode. We aimed to assess protection at 10 years of follow-up.

Methods: In this retrospective cohort study, cohorts of patients treated for cholera (index patients) and contemporaneously selected age-matched individuals without cholera (controls), randomly selected from the population of Matlab, Bangladesh, were assembled between 1990 and 2009 and followed for up to 10 years.

Assembly and performance of a cholera RDT prototype that detects both and associated bacteriophage as a proxy for pathogen detection.

Cholera rapid diagnostic tests (RDTs) are vulnerable to virulent bacteriophage predation. We hypothesized that an enhanced cholera RDT that detects the common virulent bacteriophage ICP1 might serve as a proxy for pathogen detection. We previously developed a monoclonal antibody (mAb) to the ICP1 major capsid protein.

Age-dependent pathogenic profiles of enterotoxigenic diarrhea in Bangladesh.

Background: Age plays a significant role in susceptibility to enterotoxigenic (ETEC) infections, yet the distribution of ETEC virulence factors across age groups remains understudied. This study investigated the differential pathogenic profiles ETEC across various age groups, emphasizing the importance of selecting potential ETEC antigens tailored to infection patterns in infants and adults in Bangladesh.

Methods: This study utilized the icddr,b's 2% systematic hospital surveillance data of diarrheal patients ( = 14,515) from 2017 to 2022 to examine the age-specific pathogenesis and clinical manifestations of ETEC infections.

Coinfection and clinical impact of enterotoxigenic Escherichia coli harboring diverse toxin variants and colonization factors: 2017-2022.

Objectives: The severity of the diarrhea disease is exacerbated by co-infections that involve Enterotoxigenic Escherichia coli (ETEC) and other enteric pathogens, which complicate the diagnosis and treatment. This study explores the prevalence, clinical manifestations, and risk factors of ETEC and its co-infections in Dhaka, Bangladesh.

Methods: The study used data from the Diarrheal Disease Surveillance System at Dhaka Hospital, involving 16,276 patients from 2017 to 2022.

Antibiotic resistance and serotype distribution of strains in Bangladesh over the period of 2014-2022: evidence from a nationwide hospital-based surveillance for cholera and other diarrheal diseases.

Unlabelled: The objective of this study was to assess the prevalence, antimicrobial resistance patterns, and risk factors linked to infections through a nationwide hospital-based diarrheal disease surveillance in Bangladesh. From May 2014 to May 2022, from a systematic sentinel surveillance of infections in over 10 hospitals across Bangladesh, stool specimens were collected from patients with acute watery diarrhea and tested for species by microbiological culture. The susceptibility to antibiotics was tested using the disk diffusion method.

Core and accessory genomic traits of Vibrio cholerae O1 drive lineage transmission and disease severity.

In Bangladesh, Vibrio cholerae lineages are undergoing genomic evolution, with increased virulence and spreading ability. However, our understanding of the genomic determinants influencing lineage transmission and disease severity remains incomplete. Here, we developed a computational framework using machine-learning, genome scale metabolic modelling (GSSM) and 3D structural analysis, to identify V.

Development of a Shigella conjugate vaccine targeting Shigella flexneri 6 that is immunogenic and provides protection against virulent challenge.

Immunity protective against shigella infection targets the bacterial O-specific polysaccharide (OSP) component of lipopolysaccharide. A multivalent shigella vaccine would ideally target the most common global Shigella species and serotypes such as Shigella flexneri 2a, S. flexneri 3a, S.

Determinants of immune responses predictive of protection against shigellosis in an endemic zone: a systems analysis of antibody profiles and function.

Background: Shigella is the third leading global cause of moderate or severe diarrhoea among children younger than 5 years globally, and is the leading cause in children aged 24-59 months. The mechanism of protection against Shigella infection and disease in endemic areas is uncertain. We aimed to compare the Shigella-specific antibody responses in individuals living in Shigella-endemic and non-endemic areas, and to identify correlates of protection in a Shigella-endemic location.

Spatial and temporal clustering of typhoid fever in an urban slum of Dhaka City: Implications for targeted typhoid vaccination.

Background: Salmonella enterica serotype Typhi (Salmonella Typhi) causes severe and occasionally life-threatening disease, transmitted through contaminated food and water. Humans are the only reservoir, inadequate water, sanitation, and hygiene infrastructure increases risk of typhoid. High-quality data to assess spatial and temporal relationships in disease dynamics are scarce.

Annual risk of hepatitis E virus infection and seroreversion: Insights from a serological cohort in Sitakunda, Bangladesh.

Hepatitis E virus (HEV) is a major cause of acute jaundice in South Asia. Gaps in our understanding of transmission are driven by non-specific symptoms and scarcity of diagnostics, impeding rational control strategies. In this context, serological data can provide important proxy measures of infection.