Twenty years after a first survey, a follow-up study was performed on the p
revalence of MS in Enna (Sicily), southern Italy. The prevalence of definit
e MS rose from 53 to 120.2 per 100,000 population. The incidence of definit
e MS for the period 1986 to 1995 was 5.7 per 100,000 per Year. The innermos
t part of Sicily shows an elevated prevalence of MS, second only to Sardini
a in the Mediterranean area.