Genetic relationships among strains ofNeisseria meningitidiscausing disease in Italy, 1984–7

Abstract

SUMMARY: Since 1984 a change in the epidemiological pattern of meningococcal disease in Italy has occurred with a predominance ofNeisseria meningitidisof serogroup C (76%), serotype 2a and a high proportion of strains resistant to sulphonamides (71%). In order to understand better the epidemiology of the groupC N. meningitidisstrains responsible for the disease over the last years in Italy, we studied the genetic features of phenotypically closely related strains, by enzyme electrophoresis. The results showed that the genetic and the phenotypic characteristics of the 57 strains studied were similar, suggesting the spread of a single clone during recent years in our country.This result is in agreement with the circulation of strains typical of epidemic situations, despite the decreasing incidence of meningoccal disease in Italy.