Hepatitis B surface and e antigen seropositivity in mothers and cord blood at Port Moresby General Hospital: implications for a control program.

ABSTRACT

PIP: 100 mother-infant pairs were tested for hepatitis B surface and e antigen and the results used to estimate effectiveness of the current vaccination program in Papua New Guinea. The 100 mothers and neonates born at the Port Moresby General Hospital in May-June 1990 were tested for HBsAg and HBeAg with the reversed passive hemagglutination technique (Green Cross Corp., Japan). 11 mothers were positive for HBsAg, and 6 of these for HBeAg. 5 cord bloods were positive for HBsAg, and 2 of these for HBeAg. 1 infant was positive for HBeAg only. All 3 infants positive for HBeAg were born of HBeAg mothers. It is assumed that HBsAg in infants is from passive transfer from the mother. HBeAg is indicative of a highly infectious state in a mother, and active infection in a newborn. It was calculated that the currently used plasma-derived vaccine, which has a protective efficacy rate (PER) of 75%, would be expected to protect 25/1000 children from becoming carriers, compared to 5/1000 more if immunoglobulin were given in addition. The higher costs of the new recombinant vaccine and of the plasma vaccine plus immunoglobulin were considered impractical.