Rationale for the infant and adolescent vaccination programmes in Italy.

In Italy in the 1980s, the incidence of acute hepatitis B was about 13 per 100,000, corresponding on average to 7500 new symptomatic cases per year was about 3%, making Italy an area of intermediate endemicity. HBV infection was also associated with 12 per 100,000 deaths from cirrhosis and with 5.1 per 100,000 deaths from hepatocellular carcinoma. In view of the large numbers of pregnant women who were hepatitis B surface antigen (HBsAg)-positive, selective hepatitis B vaccination of all newborns to these mothers and of other high-risk groups was introduced in 1983. Compliance was high among the newborns but low in other high-risk groups. Hepatitis vaccination was adopted in Italy in 1991, including each year all newborns, all adolescents aged 12 years and other high-risk groups. Compliance has been nearly 95% for newborns and 80% for adolescents. Since the introduction of vaccination, both the incidence of acute hepatitis B and the prevalence of HBV carriage have fallen, the latter from 3.4% in 1985 to 0.9% in 1996. There is good evidence that these decreases are mainly the result of the vaccination programmes. Although the full economic impact cannot yet be assessed, about 18,000 cases of acute HBV infection have been prevented over the 6 years since starting the mass vaccination programme, with cost savings of about US$ 244,308,000.