Vaccination against meningitis, currently compulsory in infants for a single family of bacteria (the meningococcus C strain), will be expanded from the start of 2025 in the face of the rebound in these serious infections, formalizing a new vaccination schedule published Friday April 26 by the health authorities.
Vaccination of children under 1 year old against meningococci A, B, W and Y – as well as C – will be compulsory from next year and will be largely reimbursed by Health Insurance, as recommended by the High Health Authority (HAS).
Currently, only meningococcal C vaccination is compulsory for children under 1 year of age; that against meningococcus B is only recommended. From 2025, a single vaccine, called tetravalent, will target A, C, W and Y; this will be the Nimenrix vaccine from Pfizer, given in two successive doses (at 6 and 12 months). Pfizer’s Bexsero vaccine, against meningococcus B, will always be given separately, in three successive doses (at 3, 5 then 12 months).
An unprecedented number of cases for ten years
In 2023, 560 cases of invasive meningococcal infections were reported, an increase of 72% compared to 2022 and a level unprecedented in ten years, according to a bulletin of Public Health France published April 9. 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 infections bacterial invasives.
The incidence was highest among children under 1 year of age (56 cases, or 8.2 cases per 100,000 inhabitants). It was also high among young adults aged 15 to 24 (101 cases, or 1.2 cases per 100,000 inhabitants).
For a long time, meningococci B and C remained in the majority. This is still the case for B. On the other hand, family C has become marginal, clearly behind Y and W, the latter being particularly murderous. Among the 560 cases declared in 2023, the serogroup was characterized for 535 cases: 240 cases of serogroup B (44%), 160 cases of serogroup W (29.4%), 130 cases of serogroup Y (23.9%). , 5 cases of serogroup C (0.9%).
Meningococci are not the only cause of meningitis, a generic term for inflammation of the membranes of the brain or spinal cord. Most of the time, a virus is the cause. But viral meningitis is generally much less serious than that caused by bacteria. The latter, which manifest themselves in particular by a high fever and a stiff neck, kill a patient devastatingly if he is not treated. And, even when it is treated, mortality remains 10%.
Not all bacterial meningitis is caused by meningococci, but they are easily transmitted from one person to another. They can therefore cause epidemics, which justified the development of vaccines.