A pregnant woman is found to be HBsAg positive. To prevent vertical transmission, what should be given to her newborn at birth?

Answer: B. Hepatitis B immunoglobulin together with the hepatitis B vaccine

Preventing vertical transmission of hepatitis B

Vertical (mother-to-child) transmission is the usual route of HBV spread worldwide, and its risk relates to the mother's replicative state (highest if HBeAg positive or high HBV DNA).

Newborn prophylaxis

• All newborns of HBsAg-positive mothers should receive combined prophylaxis: hepatitis B immunoglobulin (HBIG) for immediate passive protection plus the hepatitis B vaccine for active immunity, given at separate sites soon after birth.
• The vaccine course is then completed on schedule.

Other points

• Breastfeeding is not contraindicated once the infant has received appropriate immunoprophylaxis - HBV is not transmitted by breastfeeding.
• Mothers with very high HBV DNA may be offered antiviral therapy (e.g. tenofovir) in the third trimester to further reduce transmission.

Why combined prophylaxis

Passive HBIG gives immediate antibody while the vaccine induces lasting active immunity - together they substantially reduce perinatal transmission.