Key Points

The past five years (2017–2021) have been marked by several events:

• a measles outbreak in 2018–2019 across the country, with several clusters identified (including several in the Centre-Val de Loire region). The majority of cases were not fully vaccinated (92% of cases in the region)

• A hepatitis A outbreak in 2017–2018 in France, primarily among men who have sex with men (MSM). Several outbreaks unrelated to the MSM population were also identified in the region

• resurgence of Legionnaires’ disease during the summers of 2018 and 2021, likely linked to favorable weather conditions

• vaccination against type C meningococcal infections (IIM) made mandatory for all infants born on or after January 1, 2018, and vaccination recommended against type B IIM starting at age 2

• Since March 2020, the implementation of preventive measures in response to the COVID-19 pandemic (mask-wearing, social distancing, curfews, travel restrictions, etc.) has reduced the incidence of several diseases such as measles, meningitis, hepatitis A, and foodborne illness outbreaks

• For several diseases, a return to normal levels (tularemia) or even an increase in incidence (listeriosis) has been observed starting in 2021