A plasma subunit vaccine against hepatitis B studied in field trials

The work presents materials on the study of subunit plasma vaccine against hepatitis B (HB), developed in the USSR, in a controlled epidemiological trial. The study showed low reactogenicity and complete safety of the preparation, the level of anti-HBsAg antibodies in persons, formerly found to have no such antibodies, being 88% after three injections of the vaccine. To determine the prophylactic effectiveness of the vaccine, the test and control groups, each consisting of 500 children, were formed from children aged 1-3 years, i.e. belonging to the age group most frequently affected by HB, by the method of random choice. During 18 months from the time of immunization no cases of HB were registered among the vaccinees, while in the control group 5 cases of HB were registered (8.9 per 1000). These results indicate that the plasma vaccine against HB, newly developed in the USSR, is faintly reactogenic, safe and shows sufficiently high antigenic activity and protective potency correlating with this activity.