RESUMO
In order to ascertain the real frequency of HAV infection in North-East of Italy a seroepidemiologic survey was carried out on the population of Padova and its district. The serum samples obtained from 1812 subjects (approximately the 2% of registered people) subdivided according to sex and age (5 to 5 year groups), were tested for anti-HA by radioimmunoassay. The mean prevalence of anti-HA was 69.2%. Positive subjects' frequency of 50% was reached in 15-20 year-old group, whereas more than 90% of people over 35 years of age were positive. No significant differences were observed between the sexes or between town and country populations, while the increase of the anti-HA prevalence curve was delayed in the higher socioeconomic level group. These findings testify the relevant socioeconomic and public health levels improvement in the last decades, while, on the other hand, point out the increasing risk of adulthood HAV infection.