Abstract
Eight infants who developed HBsAg aged between 1 and 5 months were identified in the greater Copenhagen area during the period 1970--76. 7 had acquired the infection from their mothers and one had received a HBsAg-positive blood infusion, 3 infants had a transient infection lasting 2 to 8 months while the remaining cases developed persistent antigenaemia with evidence of minor liver dysfunction during a follow-up of one to 6 years. HBeAg was persistently present in 4 of 5 infants, indicating infectivity in these patients. Prematurity or administration of specific immunoglobulin at delivery apparently did not affect the course of infection.