Annual incidence, prevalence, and mortality of multiple sclerosis in white South-African-born and in white immigrants to South Africa.

Abstract

On settling in South Africa in 1947 I learned that multiple sclerosis (M.S.), or disseminated sclerosis as it was usually called, was thought to be uncommon among South Africans. I therefore proceeded with a study of all white patients diag nosed as having this disease at the major South African hospitals and found that 14 out of 27 in whom the diagnosis could be accepted as probable in 1948 were immigrants from Europe, though immigrants were only 10% of the population at risk. Among ?the South-African born White population the disease was apparently uncommon.1 The present study extended from 1958 to 1966. A full account of the methods used for case ascertainment and of the comparative surveys which were made of the healthy population at risk will be published separately. Over the eight years of this study every means possible was sought to discover and investigate patients suspected of having M.S. All the South African physicians and neurologists co-operated in supplying the names and medical histories of patients who might have M.S. The records of the major hospitals were searched. Repeated articles and three editorials appeared in the South African Medical Journal about the survey, also articles in the popular press and radio reports. Personal letters were sent on two occasions to every doctor in practice in South Africa. A Multiple Sclerosis Society was formed, and this helped greatly with publicity and in tracing patients. Every effort was made to see that all cases of possible M.S. were fully investigated by competent neurologists. Ninety-four per cent, of the patients having probable M.S. on prevalence day were also personally examined by me. All death certificates since 1949 in which