[Meningococcal meningitis in Italy: 1887-1986].

We report the epidemiological data relative to meningococcal meningitis observed through a century, 1887-1986, in Italy. It is evident both from mortality and morbidity data that in Italy three epidemic peaks have occurred in 1915-1918, in 1939-1943 and in 1968-1972 respectively. The first two epidemic episodes are likely to be connected with the World Wars, the third one, recorded in other european and non european countries, probably reflects a pandemic recrudescence of the disease. The case fatality rate has shown periodic fluctuations connected with the epidemics and an average value of 10% until the sixties. Since then, the case fatality rate has stably decreased below that value. The seasonal distribution of the disease is similar both in the epidemic or non-epidemic period, with the higher incidence of cases between December and April and the lowest in August. There are no substantial differences in the regional distribution of the disease among the various regions of Italy. The distribution of cases, according to the different age-groups (0-14, 14-25, greater than 25 years old), indicates that the disease is more prevalent among the first group. However, in the last decade it is evident a trend of reduction among this group and a relative increase in other groups, in particular in subjects older than 25 years. In addition, meningococcal meningitis is prevalent among the males in the first two decades of life (less than 25 years old) while, afterward, there is an equal incidence both in males and females. The higher prevalence suggests a role of various close environmental contacts, such as the military service.(ABSTRACT TRUNCATED AT 250 WORDS)