Background Epidemiology Transmitted perinatally during delivery (rarely transmitted in utero)
Highest risk is with acute infection during the third trimester
Transmission from HBaAg-positive mothers is 30% if HBeAg-negative and 85% if HBeAg-positive Clinical Manifestations 80-90% of infected infants will develop chronic infection
Mostly asymptomatic Prevention Mother should take tenofovir starting at 28-32 weeks gestation if viral load is greater than 200,000 IU/mL, until 3 months postpartum
If mother has active hepatitis B (that is, HBsAg is positive) or if her status is unknown, then consider post-exposure prophylaxis with hepatitis B immune globulin and hepatitis B vaccine given within 12 hours of life
Vaccine prevents about 90% of infections, with HBIG adding a bit more
HBIG can be given up to 7 days of life but is most effective when given earlier
Vaccine and HBIG should be given in separate limbs
Overall, decreases transmission from 30-85% down to 1-2%
No need for Cesarean section to prevent transmission
Monitoring
Completion of routine vaccination schedule
If the birth weight is less than 2000 g, the birth dose should not count towards their vaccine series
Postvaccination HBsAg serology is recommended for children born to HBsAg-positive mothers
Usually at age 9 to 12 months
HBsAg negative with HBsAb ≥10 mIU/mL: no further management
HBsAg negative with HBsAb <10 mIU/mL: give another dose of vaccine and repeat testing in 1 to 2 months
If still <10 mIU/mL, then give two additional doses to complete a full second series and repeat testing in 1 to 2 months
HBsAg positive: refer for management
Even if not infected, maternal HBcAb may persist in the baby up to 24 months of age
Recommend breastfeeding if the infant received appropriate prophylaxis
Remember to screen other family members for hepatitis B
Also see article on neonatal HIV Further Reading Prevention of Hepatitis B Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices. MMWR Recomm Rep . 2018;67(RR-1):1-31. doi: 10.15585/mmwr.rr6701a1
