Perinatal transmission of hepatitis B in rural Bangladesh

Abstract

Objective: Estimate the relative importance of perinatal transmission of hepatitis B in Bangladesh. Methodology: Paired-serum samples (330 mothers and their 334 infants) were tested for hepatitis B markers in a cross-sectional study. Infants were aged 2-8 months (-40 per age month), and cord blood was drawn from 33 deliveries. Laboratory personnel were kept blind on any information regarding the individual. The study evaluated hepatitis B core (HBcAg), surface antigen (HBsAg) and e-antigen (HBeAg) using a commercial ELISA test kit. All samples were screened for HBcAg and those testing positive were further tested for HBsAg. Those positive for HBsAg were, in rum, tested for HBeAg. Results: The mothers were young and of low parity, with a mean (SD) height of 150 (5.4) cm. The mean birth weight of 33 infants delivered at the hospital was 2.5 (0.46) kg. In maternal samples, 107 (32.4%) were positive for HBcAg, 18 (5.4%) for HBsAg, and 4 (1.2%) for HBeAg. In infant samples, 35 (10.5%) were positive for HBcAg, 1 (0.3%) for HBsAg, and none for HBeAg. Of the 35 HBcAg-positive infants, only 1 was an offspring from a HBcAg-negative mother, and was a 7-month old girl who was otherwise HBsAg-negative. Of the 18 HBsAg-positive mothers, 4 (22%) were HBeAg-positive. All 14 children of the mothers who were HBeAg-negative were negative for HBsAg. Only one of four (25%) of the children of the HBeAg-positive mothers was HBsAg carrier (8 months old), and in three children, transmission did not occur (two 8 months old, one 6 months old). Conclusion: Hepatitis B is prevalent in rural Bangladesh. Perinatal transmission mode is relatively low. HBsAg-positive and negative for e-antigen mothers do not infect their babies. The low transmissibility of surface antigen to infants reported in this study contrasts with the published reports from other developing countries