Research SummaryMolecular and environmental determinants of norovirus disease and transmission
Norovirus, with 6 genogroups (GI to GVI) and >40 genotypes, is a significant cause of gastroenteritis in many developed countries. GII.4 strains are the most common and new variants emerge every 2 to 4 years, possibly due to recombination and genetic drift driven by population immunity. There is paucity of data on the burden and strain distribution of noroviruses from developing countries such as India. This study will measure the burden and antibody responses to norovirus infection and study the evolution of norovirus strains in India. We will estimate the burden through a prospective case-control study of children admitted with gastroenteritis in a large hospital. Antibody responses in norovirus gastroenteritis will be studied using a large biorepository of multiple sera from a birth cohort with linked epidemiologic data. Norovirus strains collected over 10 years will be genotyped using real-time PCR, and next generation sequencing to describe strain distribution and virus evolution. These studies will result in a comprehensive overview of norovirus infections and disease in India--such data combining community and hospital data with antibody response and detailed strain characterization are not currently available from any low- or middle income country.
Figure Legend: Schematic representation of the proposed study. The three main components of the study are; i) evaluate antibody responses to norovirus gastroenteritis in an Indian birth cohort; ii) evaluate burden of severe gastroenteritis due to norovirus in children <5 years; iii) study of norovirus GII.4 evolution.