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.

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.

Clinical surveillance systems obscure the true cholera infection burden in an endemic region.

Our understanding of cholera transmission and burden largely relies on clinic-based surveillance, which can obscure trends, bias burden estimates and limit the impact of targeted cholera-prevention measures. Serological surveillance provides a complementary approach to monitoring infections, although the link between serologically derived infections and medically attended disease incidence-shaped by immunological, behavioral and clinical factors-remains poorly understood. We unravel this cascade in a cholera-endemic Bangladeshi community by integrating clinic-based surveillance, healthcare-seeking and longitudinal serological data through statistical modeling.

Appearance of tolerance-induction and non-inflammatory SARS-CoV-2 spike-specific IgG4 antibodies after COVID-19 booster vaccinations.

Background: Understanding the characteristics of the humoral immune responses following COVID-19 vaccinations is crucial for refining vaccination strategies and predicting immune responses to emerging SARS-CoV-2 variants.

Methods: A longitudinal analysis of SARS-CoV-2 spike receptor binding domain (RBD) specific IgG antibody responses, encompassing IgG subclasses IgG1, IgG2, IgG3, and IgG4 was performed. Participants received four mRNA vaccine doses (group 1; n=10) or two ChAdOx1 nCoV-19 and two mRNA booster doses (group 2; n=19) in Bangladesh over two years.

National Hospital-Based Sentinel Surveillance for Cholera in Bangladesh: Epidemiological Results from 2014 to 2021.

Despite focusing on cholera burden, epidemiologic studies in Bangladesh tend to be limited in geographic scope. National-level cholera surveillance data can help inform cholera control strategies and assess the effectiveness of preventive measures. Hospital-based sentinel surveillance among patients with suspected diarrhea in different sites across Bangladesh has been conducted since 2014.

Estimating the gap between clinical cholera and true community infections: findings from an integrated surveillance study in an endemic region of Bangladesh.

Our understanding of cholera transmission and burden largely rely on clinic-based surveillance, which can obscure trends, bias burden estimates and limit the impact of targeted cholera-prevention measures. Serologic surveillance provides a complementary approach to monitoring infections, though the link between serologically-derived infections and medically-attended disease - shaped by immunological, behavioral, and clinical factors - remains poorly understood. We unravel this cascade in a cholera-endemic Bangladeshi community by integrating clinic-based surveillance, healthcare seeking, and longitudinal serological data through statistical modeling.

Implementation and Delivery of Oral Cholera Vaccination Campaigns in Humanitarian Crisis Settings among Rohingya Myanmar nationals in Cox's Bazar, Bangladesh.

Background: Over 700,000 Myanmar nationals known as the 'Rohingyas' fled into Cox's Bazar, Bangladesh, in late 2017. Due to this huge displacement into unhygienic areas, these people became vulnerable to communicable diseases including cholera. Assessing the risk, the Government of Bangladesh (GoB), with the help of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B) and other international partners, decided to take preventive measures, one of which is the execution of oral cholera vaccination (OCV) campaigns.

COVID-19 hospitalization with later long COVID in a person with Down syndrome.

Viruses that induce pulmonary difficulties and auto-inflammation are more common in people with Down syndrome. They also have a higher number of comorbidities associated with a worse prognosis than the overall population. Adult patients with acute COVID-19 are increasingly being diagnosed with Long COVID.

COVID-19 and dengue infection in Bangladesh: A case of coinfection where hemoptysis as first presentation.

Bangladesh recently faced large outbreaks of both COVID-19 and dengue. We present a case of COVID-19 and dengue coinfection in a patient who presented with hemoptysis. Our results demonstrate that COVID-19 and dengue fever are both public health issues in Bangladesh and other dengue-endemic nations and that they can coexist.