Observations of subacute sclerosing panencephalitis in South Africa.

Analysis of 75 cases of subacute sclerosing panencephalitis (SSPE) reported to the National Institute for Virology, South Africa, in 1984-1990 does not support the role of intensive exposure to measles virus in the pathogenesis of SSPE. The incidence of SSPE per million population was similar in Blacks and Whites, although that of reported measles is up to 10 times greater in Blacks. The age of SSPE follows the distribution of measles cases; thus, significantly more younger SSPE cases were found in Blacks than in Whites. The distribution between males and females was approximately equal. These data suggest SSPE to be a fortuitous complication of measles infection associated with as yet unidentified risk factors rather than a consequence of an excessive dose of infecting virus or immunological immaturity.