Immunoprophylaxis of hepatitis A of the children by immune serum globulin.

An outbreak of hepatitis A occurred in Kyoto. Immune serum globulin was administered prophylactically to children who had not yet developed the disease. However 52 children in succession contracted hepatitis A. Late injections of immune serum globulin had no effect on the clinical course. Middle injections suppressed only jaundice. Early or preexposure injection suppressed the disease remarkably. All who had overt hepatitis A seroconverted to positive antibody to hepatitis A virus. In inapparent infection, those who had slight elevation of transaminase developed passive active immunization irrespective of pre or postexposure administration of immune serum globulin. Three children who might block hepatitis A virus completely had no change of transaminase and failed to establish passive active immunization.