Intrafamilial spread of hepatitis B virus infection in Greece.

Objective: No study has investigated the intrafamilial spread of hepatitis B virus (HBV) in Greece. We conducted a 9-year prospective study to determine the rate of HBV spread in family members when a member is identified as an HBV carrier, the possible routes and risk factors for transmission of HBV and the family members with the highest risk of infection according to kinship degrees.

Methods: A total of 387 family members of 166 hepatitis B surface antigen (HBsAg) carriers were investigated for the detection of HBV infection markers using standard enzyme immunoassays; 6.696 blood donors from the same area were used as controls.

Results: Serological markers of past or current HBV infection were detected significantly more frequently among family members of HBsAg carriers (23.2 and 15.8%, respectively) compared with blood donors (14.1 and 0.85%, respectively). The prevalence of the above markers was higher among siblings, husbands and parents of the carriers. Offspring of the female index cases had higher rates of current or past infection. HBV infection markers were significantly increased in family members who reported common use of syringes (P<0.001), birth in rural areas (P<0.001) and a low level of education (P<0.001).

Conclusions: We demonstrated a high risk of HBV transmission among family members of HBsAg carriers, which was associated with special risk factors for contracting HBV. Our findings indicate the need for strict adherence to the universal guidelines of vaccination against HBV and also the need for an immediate investigation of other potentially infected relatives among family members of HBsAg carriers.