Key Points

In 2020, 219 cases of invasive meningococcal disease (IMD) were reported in France, of which 207 had an identified serogroup: 124 (60%) cases of serogroup B, 33 (16%) cases of serogroup W, 24 (12%) cases of serogroup C, 23 (11%) cases of serogroup Y, and 3 (1.4%) cases due to another serogroup. Thirty deaths were reported, representing a case fatality rate of 13.7%.

The year 2020 was marked by a very significant decrease in the incidence of IIM, with the number of cases falling by more than half compared to 2019. The incidence began to drop in March 2020 and remained at levels significantly lower than in previous years through the end of 2020. This downward trend was observed across all serogroups and age groups. This decrease in incidence is linked to the lockdown implemented between March and May 2020, and to the measures to combat COVID-19 (social distancing, preventive measures, mask-wearing) that continued throughout 2020 and helped prevent the transmission of other respiratory pathogens.