Hepatitis B surface antigen and its subtypes in an institution for the mentally retarded.

The prevalence of hepatitis B surface antigen (HBsAg) in 155 patients with Down's syndrome (DS) and 209 with other types of mental retardation (OMR) at Huronia Regional Centre, Orillia, Ontario was 34.8 and 5.3%, respectively.

A SURVEY OF TOXOPLASMOSIS AMONG MENTALLY RETARDED CHILDREN.

To determine what role, if any, toxoplasmosis plays in the mental retardation of children, sera from 345 mentally retarded children were tested for the presence of antibodies to Toxoplasma gondii. The serological tests employed were the complement-fixation, the Sabin-Feldman dye test and the immunofluorescence test. The donors were also skin-tested with toxoplasmin.