Avoidance of perinatal transmission of hepatitis B virus: is passive immunisation always necessary?

Screening of 8918 pregnant women revealed that 107 (1.2%) were HBsAg-positive. 92 of them (50 of German and 42 of predominantly Asian origin) have already delivered and were followed up for 12 months together with their infants. 14 infants of HBeAg-positive (or anti-HBe-negative) carrier mothers received a single dose of hepatitis B immunoglobulin (HBIG) immediately after birth, while 60 infants of anti-HBe-positive mothers were not immunised. 57 of the 60 "unprotected" children remained seronegative for HBsAg and HBeAg. 3 children showed HBs-antigenaemia immediately after birth; 2 of these lost HBsAg and developed anti-HBs after 6 and 9 months. The third lost HBsAg after 4 months without an antibody response developing. This suggests that the HBsAg particle only was transmitted rather than the whole virus. 12 of the 14 infants born to HBeAg-positive, or anti-HBe-negative carrier mothers were protected with one single high dose of HBIG. 2 had HBs-antigenaemia, 1 had HBeAg as well. These data show that in a West European population the risk of perinatally acquired HBV infection in the infants of anti-HBe-positive carrier mothers is small, and that passive immunisation of this group is not necessarily indicated.