A recent study conducted by France’s Institut Pasteur has disclosed a significant rise in invasive meningococcal disease, particularly post-COVID-19. This increase has been noted in younger age groups and involves different bacterial strains, highlighting the need for revised vaccination strategies to meet these evolving health risks.
The Institut Pasteur’s team analyzed data from 2015 to 2022 using the National Reference Center for Meningococci’s records. Published in the Journal of Infection and Public Health, their research shows a marked resurgence of the disease after the relaxation of COVID-19 measures.
This resurgence is characterized by a change in the pattern of the disease, with an increase in cases caused by serogroups of meningococci that were previously less prevalent. The study particularly points out the rise in infections among individuals between 16 and 24 years old. These findings are crucial for guiding changes in vaccination approaches to address this life-threatening disease.
Effects of COVID-19 Measures on IMD
During the COVID-19 crisis, practices such as mask-wearing and social distancing reduced respiratory infections, including invasive meningococcal disease, by over 75% in 2020 and 2021. But the concern arose about what would occur after the pandemic when these measures were relaxed.
Muhamed-Kheir Taha, co-lead author of the study and Director of the National Reference Center for Meningococci, noted two prevailing theories during the pandemic. One theory suggested a lasting decrease in meningococcal circulation, while the other anticipated a rapid increase in bacterial activity among a population less exposed to the bacteria.
The Institut Pasteur’s research team undertook a comprehensive study of the disease’s evolution between 2015 and 2022, confirming the latter hypothesis.
Post-Pandemic Analysis of IMD Cases
Using data from the National Reference Center for Meningococci, the researchers observed a significant increase in IMD cases in autumn 2022 and 2023, surpassing pre-COVID-19 numbers. The number of cases rose by 36% in 2023 compared to the same period in 2019.
This increase is attributed to both a general reduction in immunity due to less circulation of strains and a decline in vaccination rates, including a 20% drop in meningitis C vaccinations during the initial lockdown. The evolving nature of the bacterial genome also contributes to the population’s vulnerability.
Shifts in Meningococcal Strains and Affected Age Groups
Ala-Eddine Deghmane, another co-lead author, noted a resurgence in serogroups W and Y post-pandemic, with young adults aged 16 to 24 being particularly susceptible. The pandemic seems to have reset the dynamics of IMD, with different strains now affecting varied age groups.
Challenges and Future Vaccine Strategies
With the upcoming flu season, there’s a potential increase in meningitis cases, as the flu virus provides a conducive environment for meningococcal bacteria. Current vaccination strategies in France cover only meningitis C, with B recommended for infants. However, there are no widespread recommendations for serogroups Y and W.
The researchers are consulting with health authorities to adapt vaccine strategies, suggesting a quadrivalent vaccine covering serogroups A, C, Y, and W, especially for adolescents. Given the high mortality rates associated with untreated bacterial meningitis, and a 10% mortality rate even with treatment, vaccination remains a critical preventive measure.
Reference: “The rapid rebound of invasive meningococcal disease in France at the end of 2022” by Samy Taha et al., 12 October 2023, Journal of Infection and Public Health.
DOI: 10.1016/j.jiph.2023.10.001
Table of Contents
Frequently Asked Questions (FAQs) about meningitis resurgence France
What does the Institut Pasteur’s study reveal about meningitis post-COVID-19?
The study by the Institut Pasteur indicates a significant increase in invasive meningococcal disease in France, particularly among young adults aged 16-24, following the relaxation of COVID-19 restrictions. This resurgence involves different bacterial strains and underlines the need for updated vaccination strategies.
How did COVID-19 measures affect invasive meningococcal disease (IMD)?
During the COVID-19 pandemic, preventive measures like mask-wearing and social distancing led to a more than 75% reduction in IMD cases in 2020 and 2021. However, with the easing of these measures, there was a notable resurgence in IMD cases.
What changes in meningococcal disease patterns were observed post-pandemic?
Post-pandemic, there has been a shift in the disease pattern with a rise in cases caused by meningococcal serogroups W and Y, which were previously less common. The most affected age group is now young adults between 16 and 24 years old.
What are the implications of the study for future vaccine strategies?
The study suggests the need for revising vaccine strategies, potentially including a quadrivalent vaccine covering serogroups A, C, Y, and W, especially targeting adolescents. This is crucial given the high mortality rate associated with bacterial meningitis.
What was the methodology used in the Institut Pasteur’s study?
The Institut Pasteur team analyzed data from the National Reference Center for Meningococci, covering the progression of IMD in France from 2015 to 2022. This involved comparing IMD cases before, during, and after the COVID-19 pandemic.
More about meningitis resurgence France
- Institut Pasteur
- Journal of Infection and Public Health
- National Reference Center for Meningococci
- COVID-19 and Respiratory Infections
- Meningococcal Disease Information
