Diversity of Neisseria meningitidis invasive isolates in Italy in the period 2008-2010.

In the period 2008-2010, 309 Neisseria meningitidis, isolated in Italy within the National Surveillance of the Invasive Meningococcal Diseases, have been tested for their phenotypic and genotypic characteristics. The main results obtained are: (a) an increase of the strains of serogroup B and a decrease of serogroup C; (b) a phenotypic and genotypic variability of the ST-41/44 clonal complex, the most frequently isolated among serogroup B strains; (c) a decrease of ST-8 clonal complex among serogroup C meningococci whereas strains belonging to ST-11 clonal complex are nowadays the most frequently isolated.