Cases of meningococcal meningitis at their highest: causes, affected regions, vaccination… update on the situation

Seul le vaccin contre le méningocoque C est obligatoire chez les bébés. Illustration MAXPPP – CORTIER CLAUDE

Auvergne-Rhône-Alpes, 'Île-de-France and Occitanie are the three regions most affected by cases of meningococcal meningitis in 2023, a year during which the incidence of this type of # 39;infection increased very sharply Public Health France alert this Wednesday, April 10. 

A significant increase. In 2023, the incidence of invasive meningococcal infections saw a sharp increase with a number of reported cases unprecedented for 10 years, according to a Public Health France bulletin published Wednesday.

Meningococci are a family of bacteria that cause very dangerous and contagious meningitis, mainly in children and adolescents.

72% increase

In 2023, 560 cases of invasive meningococcal infections were reported, an increase of 72% compared to 2022 and an unprecedented level for ten years.

This post-Covid 19 resurgence could be explained by the drop in immunity in the population less exposed to meningococci during the pandemic, but also by the return of respiratory viruses (in particularly  flu) which can promote invasive bacterial infections, underlines Public Health France.

The incidence rate of reported cases was highest among children under one year of age (56 cases, or 8.2 cases/100,000 inhabitants) and was also high among young adults aged 15 to 24. years (101 cases, or 1.2 cases/100,000 inhabitants).

Which regions are most affected ?

The incidence rates of reported cases varied depending on the region of residence, indicates Santé Publique France. The Géodes map shows that the Auvergne-Rhône-Alpes region is much more affected, with 93 cases recorded in 2023. Next comes Île-de-France (83 cases) then Occitanie ( 64 cases).

Where is vaccination ?

These data contributed to the work of the High Authority for Health on the revision of the vaccination strategy against meningococci, indicates Public Health France.

At present, only anti-meningococcal B and C vaccinations are concerned. Vaccination against meningococci C is compulsory for children under one year of age, while vaccination against B is only recommended.

What are we talking about ?

The main meningococci are separated into large families: A, B, C, W and Y. For a long time, B and C remained in the majority. This is still the case for B. But C has become marginal, clearly behind Y and W, the latter being particularly deadly.

Among the 560 cases reported in 2023, the serogroup was characterized for 545 cases (97%): 240 cases of serogroup B (44%), 160 cases of serogroup W (29.4%), 130 cases of serogroup Y (23.9%), five cases of serogroup C (0.9%).

Announcements to come ?

Following the recommendations of the HAS, the government should soon announce that vaccination will become much broader. In infants, first, where vaccination against all strains (A, B, C, W and Y) will be compulsory.

In adolescents, then, a booster dose against A, C, W and Y will be recommended between 11 and 14 years old, even if they have already received this vaccine at a young age .