Hepatitis B in children in Italy: incidence and risk factors: SEIEVA Collaborating Group. Sistema Epidemiologico Integrato dell'Epatite virale Acuta.

The objectives of the present report were to give a baseline picture of hepatitis B notification incidence rates in children before the campaign of mass vaccination for newborns and adolescents (12-13 years old), and to study the role of different risk factors. Data from a specific national surveillance system of acute viral hepatitis (SEIEVA, Sistema Epidemiologico Integrato dell'Epatite Virale Acuta) were used and acute hepatitis B cases were compared to acute hepatitis A patients with the case-control study method to estimate the associations with the considered risk factors. Since the system began, one hundred and sixty-three local health departments have joined SEIEVA covering 30% of the Italian population. The incidence of acute hepatitis B notifications among 0-14 aged children was 9 per 100,000 in 1985 and 1 per 100,000 in 1990. Such decline in incidence was observed in both the North and the South of Italy. Surgical interventions, dental therapy and household contacts with a HBsAg chronic carrier were found to be associated with acute hepatitis B. The point estimate of the odds ratio was 10 for the latter risk factor. Other preventive measures in addition to vaccination are needed to control the risk of hepatitis B infection and other parenteral diseases due to surgical intervention and dental therapy.