Hepatitis A in Peru. The role of children.

A serologic survey in 1983-1984 evaluated the presence of hepatitis A antibody (anti-HAV) and hepatitis A immunoglobulin M antibody (anti-HAV IgM) in 3,251 adults and 811 children in the jungle and coastal areas of Peru. All subjects were asymptomatic. Adults had a 98% positive anti-HAV rate except for naval cadets, who had a 76% rate. Children had an 82% positive anti-HAV rate, increasing from 30% at one year of age to 100% at eight years of age. Anti-HAV IgM was present in 27% of children one to four years of age who had antibody and was not present in those older than 12. The vast majority of Peruvian adults are immune to hepatitis A, and children with asymptomatic infection play a significant role in the transmission of this disease.