In 2023, 560 cases of invasive meningococcal infections were reported, an increase of 72% compared to 2022 and an unprecedented level for ten years, according to a bulletin published this Wednesday by Public Health France. Meningococci are a family of bacteria that cause very dangerous and contagious meningitis, mainly in children and adolescents.
This post-Covid-19 resurgence could be explained by the decline in immunity in the population less exposed to meningococci during the pandemic, but also by the return of respiratory viruses (in particular influenza) 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 (101 cases , or 1.2 cases/100,000 inhabitants).
Vaccinate more widely
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 declared 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%). 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.
Currently, 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. 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 of age, even if they have already received this vaccine at a young age.