Seroepidemiological study on Prevalence of antibodies against the Hepatitis A virus in the Province of Siena (Italy) in 1992

The availability of serum samples collected in 1992 from subjects divided according to age, sex and residence, provided the opportunity to carry out a seroepidemiological survey in order to ascertain the prevalence of HAV infection in the population of Siena and its Province, in recent years. This study showed a progressive increase in the percentage of subjects having anti-HAV with the rise of age. Only 3.6% of the children's sera and 8.29% of subjects aged between 10 and 20 showed the presence of anti-HAV. The statistical analysis showed 3 cohorts of subjects: under 30, between 30 and 50 and over 50 years. The cohorts correspond at 3 different periods of circulation of HAV. No differences were observed between males and females. No differences were evident between subjects from urban areas and those resident in rural districts. The comparison between subjects from the Municipalities with adequately treated waste water and subjects from Municipalities without such treatment plants showed no significant difference in the prevalence of anti-HAV antibodies.