Post-exposure active immunoprophylaxis of spouses of acute viral hepatitis B patients

Post-exposure efficacy of hepatitis B vaccine was evaluated in susceptible sexual partners of acute hepatitis B patients in a randomized double-blind, placebo-controlled trial in Greece. Vaccine (20 micrograms dose) or placebo was repeated one and six months after initial administration. Nine months' follow-up was completed by 146/160 entrants. Vaccinated (16.0%) and control spouses (18.3%) showed similar attack rates for all infections. The vaccine group had fewer clinical infections (2.7% against 7.0%) and fewer infections occurring more than one month after first vaccination (8.7% against 14.7%). These differences are not statistically significant, but suggest modification of infection. Overall, the attack rate was lower (p less than 0.01) for male spouses (6.4%) than for females (22.4%). It may be necessary to complement hepatitis B vaccination with hepatitis B immunoglobulin to protect this high-risk group.