[Hepatitis A antibody: placental transmission and disappearance in the first year of life (author's transl)].

Sera of 114 mothers and their newborn (cord blood) were tested for the presence of antibodies to hepatitis A virus (Anti-HAV) by a competitive solid phase radioimmunoassay. Antibodies were detectable in 80 pairs of sera but not in another 31 pairs. 3 newborns proved to be anti-HAV positive, while their mothers had not detectable antibodies. 72 infants could be followed up for about one year. The disappearance of antibodies occurred between the first and 14th month of life. 50% of the tested infants were still(Anti-HAV positive at the age of 7-8 months.