[Studies of diseases caused by hepatitis B virus on the island of Favignana].

731 serum samples were drawn from inhabitants of Favignana (Egadi Islands, total population 3,000). Presence of HBsAg and anti HBs was tested by R.I.A. Although only two cases of B Virus Hepatitis had been observed in the last 3 years, the overall positivity for HBsAg was 4.8% and for anti HBs 31.6%, showing a distribution by age and sex comparable to that observed in similar studies. The rather high prevalence of HBsAg in males over 70 deserves further investigations.