Increased incidence of invasive meningococcal disease of serogroup C / clonal complex 11, Tuscany, Italy, 2015 to 2016

We report an increase of serogroup C Neisseria meningitidis invasive meningococcal disease in Tuscany. From January 2015 to end February 2016, 43 cases were reported, among which 10 were fatal, compared to two cases caused by serogroup C recorded in 2014 and three in 2013. No secondary cases occurred. Thirty-five strains belonged to C: P1.5-1,10-8: F3-6: ST-11(cc11). Control measures have been adopted and immunisation campaigns implemented. Studies on risk factors and carriage are ongoing. In this report we present an unexpected increase of invasive meningococcal disease (IMD) in Tuscany, Italy, since January 2015, leading to a total of 43 cases, of whom 10 were fatal, due to infection with serogroup C Neisseria meningitidis. In Italy, serogroup C is the second most common serogroup (31% of the 115 cases with a known serogroup in 2014), after serogroup B (48% of the 115 cases in 2014) [1]. In Tuscany, the total number of IMD cases was 16 in 2014 and 12 in 2013, with two and three cases caused by serogroup C, respectively [1].