EPIDEMIOLOGY OF MULTIPLE SCLEROSIS AND A POSSIBLE VIRUS ÆTIOLOGY

摘要: Abstract Epidemiological studies have produced important information about multiple sclerosis (M.s.) although the aetiology of this disease remains obscure. There has been no apparent change in M.S. rates over time few areas where solid data are available. The northern hemisphere increase from equator to north temperate zones. at a given latitude vary, however, implying that is not sole determinant. Information migrant suggests adult migrants high-risk low-risk higher rate than those born areas, but for most part their as high area. some indicating adults migrating do develop which implies form protection and raises possibility preventing Evidence accumulating risk determinants occur around adolescence. age-of-onset curve almost unique, with sharp peak age 30 very new cases before 15 or 55. Sex differences striking. Other latitude, consistent environmental factors documented, recent evidence critical adolescence it possible events period would be revealing. Measles-antibody titre slightly among patients controls, epidemiological implications obscure, since geographical patterns measles dissimilar. An infectious an attractive hypothesis view distribution, on migrants, curve. observed patterns, compatible models simple virus infections slow viruses best explained terms two distinct determinants, one causal preventive.