[Safety observation of attenuated live hepatitis B vaccine (H2 strain) in humans]

3089 healthy persons, aged 4 to 27 years, have been inoculated in 3 batches with attenuated live hepatitis A vaccine (H2 strain) since May, 1987. Each subject received 10(8.5) TCID dosage subcutaneously in the upper arm. None of the recipients developed any local or systemic reaction during a 42-day followup after vaccination. The serum enzyme activities, including SGPT/ALT and LDH5, were within normal range during the 4th to 16th weeks of serial tests after inoculation. The study of hepatitis A virus (HAV) shedding in feces of 4 subjects showed that no hepatitis A antigen (HAAg) was detected with antigen capture ELISA, but infectious HAV was recovered from stool-cell cultures in three of four recipients. No patient with hepatitis A was found within 6 months after vaccination in the institution where the HAV vaccine was used. In addition, no immunological evidence was seen that the HAV vaccine recipients can transmit HAV after the investigation of serological epidemiology at a class in which the HAV vaccine was tested. It is suggested that the potential of hepatitis A related to HAV vaccine among the non-vaccinated persons is rare. Seroconversion occurred at a mean time of 2 to 5 weeks after inoculation, and the positive rate of specific antibody was 95.6%.