A 45 day old infant developed icterus and two days later symptoms and signs of acute liver failure appeared. Child was found to be positive for HbsAg. The mother was also HBsAg carrier. The mother's hepatitis B serological profile is likely to be:: (A) HbsAg positive, (B) HbsAg and HbeAg positivity, (C) HbsAg and anti-Hbe antibody positivity, (D) Mother infected with mutant HBV
Answer is B. Most impoant risk factor that determines perinatal transmission of Hepatitis B is HBeAg HBsAg carrier mothers who are HBe Ag positive almost invariably (> 90%) transfer infection to their offspring.