Protective efficacy of a recombinant DNA hepatitis B vaccine in neonates of HBe antigen-positive mothers
Y. Poovorawan, S. Sanpavat, W. Pongpunlert, S. Chumdermpadetsuk, P. Sentrakul and A. Safary
Department of Pediatrics, Faculty of Medicine, Chulalongkorn University and Hospital, Bangkok, Thailand.
We have assessed the protective efficacy of a recombinant DNA hepatitis B
vaccine alone in infants of women who were positive for the surface antigen
and the e antigen. The infants received a 10-micrograms dose of the vaccine
within 12 hours of birth and additional doses 1, 2, and 12 months later. No
significant adverse reactions to vaccination were observed and the vaccine
was highly immunogenic. Only 2 (3.6%) of the 55 infants followed up to 13
months became chronically infected with the hepatitis B virus, as evidenced
by the persistent presence of hepatitis B surface antigen in serum samples.
Without immunoprophylaxis, 65% to 90% of such infants would become chronic
carriers. Immunization with a recombinant vaccine without concomitant
administration of hepatitis B immunoglobulin, therefore, considerably
decreased the incidence of the carrier state.