A recent study conducted by the Institut Pasteur has shed light on a concerning increase in invasive meningococcal disease (IMD) in France following the COVID-19 pandemic. The research, published in the Journal of Infection and Public Health, drew attention to a shift in both affected age groups and bacterial strains, prompting the need for adjustments to vaccination strategies.
During the height of the COVID-19 epidemic, strict health and hygiene measures, such as mask-wearing and social distancing, inadvertently resulted in a significant decrease in respiratory infections, including IMD. However, as the pandemic wanes and protective measures ease, the researchers anticipated a possible resurgence of bacterial activity among a population that had limited exposure to meningococci during the pandemic.
Analyzing data from the National Reference Center for Meningococci, the scientists revealed a noteworthy resurgence of IMD in autumn 2022, with the number of cases surpassing pre-COVID-19 levels. Comparing the period between January and September 2019 with the same period in 2023, there has been a 36% increase in reported cases. Additionally, there has been a rise in infections among individuals aged 16 to 24, suggesting a shift in targeted age groups.
Moreover, the study highlighted how the circulating strains of meningococcal bacteria have changed since the pandemic began. Serogroups W and Y, which were less prevalent before COVID-19, now play a dominant role in causing IMD. This finding indicates that the COVID-19 epidemic may have reset the entire system, leading to the emergence of different bacterial strains and affecting different age groups.
As the coming months may see an increase in IMD cases due to the seasonal influenza virus, there is growing concern about the potential impact on public health. Currently, meningitis C vaccination is mandatory in France, while vaccination for serogroups Y and W is not recommended in the general population. The researchers are actively collaborating with the French National Authority for Health to reevaluate vaccination strategies and potentially include the quadrivalent meningococcal vaccine as a recommendation for adolescents. This approach would not only provide direct protection for adolescents but also indirect protection for other population categories.
1. What is invasive meningococcal disease?
Invasive meningococcal disease (IMD) is a severe bacterial infection caused by Neisseria meningitidis. It can lead to meningitis (inflammation of the protective membranes surrounding the brain and spinal cord) or septicemia (blood poisoning). IMD is a potentially life-threatening condition that requires immediate medical attention.
2. How has the COVID-19 pandemic impacted invasive meningococcal disease?
During the COVID-19 pandemic, the implementation of health and hygiene measures, such as wearing masks and social distancing, inadvertently resulted in a significant decline in respiratory infections, including invasive meningococcal disease. However, as these protective measures are eased, there has been a resurgence of IMD cases.
3. What are the changes in meningococcal strains observed in France after COVID-19?
Since the onset of the COVID-19 epidemic, there has been a notable increase in cases of invasive meningococcal disease caused by serogroups W and Y. These strains were less prevalent before the pandemic and now pose a greater risk, targeting primarily young individuals aged 16 to 24.
4. What are the potential implications for vaccination strategies?
The resurgence of invasive meningococcal disease highlights the need to adapt vaccination strategies in response to evolving public health challenges. The researchers involved in the study are working closely with the French National Authority for Health to consider recommending the quadrivalent meningococcal vaccine, which provides protection against serogroups A, C, Y, and W, particularly for adolescents. This approach would not only protect adolescents but also indirectly benefit other population categories.