Population-based studies to determine enteric infection risk sub-groups in Low- and Middle-Income Countries

Cholera and hepatitis E virus (HEV) are infectious diseases transmitted by consuming contaminated or unclean food and water. There are about 6-million cholera and HEV cases reported each year, and the majority are in low- and middle-income countries (LMICs) in South Asia and Sub-Saharan Africa. Disease risk at the local-level is thought to vary based on access to safe and effective water, sanitation, and hygiene (WASH) measures. However, recent studies found that cholera and HEV do not share a common spatial risk pattern at local-levels, which is surprising since they are both transmitted by water. This suggests that other population and environmental risk factors could be driving differences in disease. Prior studies have not examined these factors or how they cluster at the population level. Also, no studies have examined how these factors change in settings where cholera and HEV vaccines have been administered. Large population-based studies are needed to identify population sub-groups at high risk for cholera and HEV, and to compare how these transmission pathways change due to vaccination. The proposed research will use novel cross-sectional representative surveys in Bangladesh to identify distinct sub-groups of clustered socio-behavioural, WASH, and environmental risk factors, then determine the association between sub-group characteristics and cholera and HEV. The research models will also be adapted to examine associations in a cross-sectional survey in a recently vaccinated population in the Democratic Republic of Congo (DRC). Findings will provide global public health experts with a better understanding of transmission pathways across LMICs, and support evidence-informed interventions to effectively reduce the burden of cholera and HEV. Additionally, the unique tools developed in this study will be flexible and can serve as a platform to be adapted for examining other water-borne infectious diseases in global populations.