Hepatitis B virus infection in children in Sardinia, Italy.

Possible hepatitis B immunization of all newborns, regardless of the mother's HBsAg status, is a strategy under consideration for selected hyperendemic areas in Italy. Sardinia is one such area. However, in 1987 in Sardinia, the prevalence of hepatitis B markers in children under 11 years was estimated at 1.7% and the prevalence of hepatitis B surface antigen (HBsAg) at 0.2%. A much higher prevalence of HBsAg was recently observed among adults in this area: 8.7% among men and 5.2% among pregnant women. This contrasting pattern is unlikely to be due to bias: the sampling procedures adopted were appropriate and the percentage of refusals was very low (2.2%). The observed low hepatitis B marker prevalence in young age groups might be the result of a cohort effect due to the improved socio-economic conditions and changes in behaviour that have occurred in Sardinia over the last few years. The finding of only 3 HBsAg+ individuals out of 1,826 children tested, in spite of the 5.2% HBsAg prevalence among pregnant women in that region, is probably attributable to the low proportion of HBeAg positive individuals among the HBsAg+ carrier mothers in this area. At present, immunization of all newborns in Sardinia cannot be recommended.