Neonatal HBV

From IDWiki

Background

Epidemiology

  • Transmitted perinatally during delivery (rarely transmitted in utero)
    • Highest risk is with acute infection during the third trimester
  • Transmission from HBsAg-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