[The determination of hepatitis A antibodies in epidemiological practice].

Epidemiological analysis of hepatitis A morbidity in a city with the population of 500,000 persons in 1960-1987 was carried out. Three periods of morbidity rises among children aged 3-6 years and 7-14 years and living at the same areas (microdistricts) were established. Blood sera from healthy children were tested for the presence of antibodies to hepatitis A in enzyme immunoassay. The data on the sanitary and bacteriological study of tap water were analyzed. Unsatisfactory results of water analysis in different microdistricts correlated with the presence of antibodies in the population of these microregions and with the average morbidity indices for many years.