Vaccination against hepatitis A virus may not be required for schoolchildren in northern India: results of a seroepidemiological survey.

OBJECTIVES To evaluate the current seroprevalence of antibodies against hepatitis A virus (HAV) in a sample of schoolchildren above 10 years of age and to determine the prevalence of HAV-induced hepatitis in adults at a tertiary care hospital in northern India between January 1992 and December 2000. METHODS Sera from 276 male and 224 female schoolchildren aged 10-17 years were tested for anti-HAV antibodies by enzyme-linked immunosorbent assay. Consecutive patients with a diagnosis of acute viral hepatitis who attended a liver clinic were tested for the serological markers of HAV, hepatitis B Virus, hepatitis C virus, hepatitis D virus, and hepatitis E virus. FINDINGS Of the male and female children, 96.3% and 98.2%, respectively had anti-HAV antibodies in their sera. The prevalence of these antibodies in the age groups 10-12, 13- 14, and 15-17 years were 98.6%, 94.8%, and 98.3% respectively. The frequency of HAV- induced acute viral hepatitis (69/870, 8%) in adults did not show an increasing trend. CONCLUSION Mass HAV vaccination may be unnecessary in northern India because the seroprevalence of protective antibodies against HAV in schoolchildren aged over 10 years remains above 95% and there has been no apparent increase in HAV-induced acute viral hepatitis in adults.