Should we be worried about the return of meningitis? Since the summer of 2022, several outbreaks of serogroup B infection have been detected, particularly in Auvergne-Rhône-Alpes and around Strasbourg, mainly in young adults. In an epidemiological update published on April 20, 2023, Public Health France confirms the resumption of cases. “After more than two years of low incidence during the COVID-19 pandemic, an upsurge in invasive meningococcal infections (IMDs) has been observed in the 2022/23 seasonconfirms the press release. A peak in incidence was observed in December 2022 (…) During the first quarter of 2023, the number of IIM cases remained at a high level (especially in January and March) compared to the incidence observed in the same months during the pre-pandemic seasons.”
Transmitted by coughing and postilions, the disease mainly affects infants and young adults and can very quickly degenerate: in 2022, 10% death have been reported among cases of meningococcal meningitis, according to SPF. “If this infection mainly affects children under five (because of their immature immunity) and 15-25 year olds (because of their behaviors which promote its spread: many close contacts, gatherings in closed environments, etc.), everyone can be concerned“, indicates to Top Health Dr. Hervé Haas, pediatrician. In December 2022 alone, 84 cases were counted, earlier than the traditional peak between January and March. And if the figures are not yet available for the beginning of the year 2023, a significant increase should nevertheless be observed.
world day against #meningitis | Infections with #meningococcus B and C are contagious and serious for infants.
Since 2022, vaccination against meningococcal B has been recommended and paid for by the@health_insurance ✅
– Ministry of Health and Prevention (@Sante_Gouv) April 24, 2023
What are the reasons for this increase? This resurgence of cases could partly be explained in particular by the end of the barrier measures, and SPF considers that this rebound is not a “unexpected phenomenon“After two years of low circulation of meningococci. The health agency puts forward two options:
- A higher risk of infection due to diminished immunity from the lack of exposure to meningococci during the health crisis;
- A season marked by the intensity of seasonal viruses, especially the flu, which can lead to a higher risk of invasive bacterial infection.
“This lag is probably linked to the precocity of other winter epidemics (flu, gastro, editor’s note), these can weaken the mucous membranes and increase the risk of invasive bacterial infections”confirms Professor Anne-Sophie Baret, epidemiologist at Public Health France, to West France.
Should meningitis vaccination be expanded?
Several types of meningococci exist. If the vaccination against meningococcal C is compulsory for infants since 2018, the one against B has only been recommended and reimbursed since last year. On the other hand, there is no obligation, neither for adults nor for children: nevertheless, 56,000 young people from Auvergne-Rhône-Alpes had been called upon to be vaccinated in August 2022, after the discovery of 16 cases, including one death. “The rebound observed in the 2022-2023 season is a reminder of the importance of vaccinating infants to protect them against infections linked to serogroups B and C“, confirms SPF.
Vaccination is indeed “the most effective way to reduce the risk of contracting this infection“, confirms Dr. Haas. Indeed, the vaccines used contain a molecule from the targeted serogroup which, once injected into the body, stimulates the production of antibodies capable of recognizing this serogroup and triggering a rapid immune response against it. Another advantage of vaccination: “By reducing the presence of meningococci in vaccinated people, it also reduces the risk of transmission to others.“, adds Dr. Haas.
“The recommendations are being reviewed and it is possible that there will be an expansion of the recommendations”nevertheless explained Professor Daniel Floret, professor of pediatrics and vice-president of the technical commission for vaccinations at the High Authority for Health, to France Inter. The new vaccination schedule for 2023 indeed indicates that the recommendations were subject to change “depending on the evolution of the number of cases”.
The vaccine is not however not effective on W and Y strains, which are now circulating more widely in the country. “Before the pandemic, the number of cases linked to W had increased fivefold in a few years, adds Anne-Sophie Barret. In 2022, it was effectively the third serogroup.” Conversely, in Belgium, the Netherlands and the United States, the vaccines available target all the strains in circulation. A request that many French pediatricians are currently making.
Source :
- Situation of invasive meningococcal infections in France as of March 31, 2023, Public Health France
