Decline of maternal hepatitis A virus antibody levels in infants

Hepatitis A is a common viral infection causing substantial morbidity and mortality. The anti-hepatitis A virus (HAV) vaccination in infants would guarantee control of the infection. However, the immunogenicity of the HAV vaccine in infants could be impaired by the presence of passively acquired maternal HAV antibodies. This study evaluated the prevalence of HAV antibodies in 103 women at delivery and in their babies in the first year of life. Eighteen mothers (17.5%) had anti-HAV serum level >10 mIU ml(1). In their infants the anti- HAV level was still positive in 11 out of 18 (61. 1%) at 12 mo. Two out of 85 infants born to anti- HAV- negative mothers and anti- HAV negative at birth were found to be positive at 5 mo of age. Conclusion: It is proposed that all women be screened at delivery for anti- HAV antibodies. Children born to anti- HAV- negative mothers could be vaccinated early during the first year of life, whereas vaccination could be postponed in children born to anti- HAV- positive mothers, if necessary.