[Epidemiology of hepatitis B (author's transl)].

A hepatitis B epidemic was observed in an institution for retarded children. The mode of transmission and the epidemiology of this disease was studied. Approximately 50% of all children in this institution were infected by the enteral route. 7 children were hospitalized with an accute episode of hepatitis B and recovered completely. 9 children showed persisting hepatitis B surface antigen and DANE-particles in the serum without clinical signs of infection. 6 of those 9 children were diagnosed as trisomy 21. All of them excrete HBs Antigen in saliva, tears and urine. 80% of family members and teaching personnel involved with these children were infected, 23% had an acute episode of hepatitis B.