Serosurvey of HAV Immunity and Single-dose Vaccine Immunogenicity Among Patients With Cirrhosis

Hepatitis A virus (HAV) superinfection in patients with cirrhosis can precipitate acute hepatic decompensation and significantly worsen outcomes. Although HAV exposure was historically universal in India, recent evidence shows declining natural immunity in adults, particularly in urban populations. Contemporary data on HAV seroprevalence and vaccine immunogenicity in Indian cirrhotics remain scarce. Updated evidence is necessary to inform national vaccination policy for chronic liver disease. This study aims to estimate the prevalence of anti-HAV IgG among adults with cirrhosis and identify predictors of non-immunity. A secondary objective is to evaluate early immunogenicity and durability of a single dose of inactivated HAV vaccine in baseline non-immune patients. This study will generate updated sero-epidemiological data and prospective evidence on single-dose HAV vaccine immunogenicity in Indian cirrhotics, providing essential guidance for HAV vaccination policies in cirrhosis. STUDY DESIGN: Observational cross-sectional study with a nested prospective cohort.