COVID-19 Pandemic Disrupts Meningococcal Disease Immunity, Raising Rebound Concerns

Strategic Insights -

Research from the Manchester Royal Infirmary has uncovered a significant decrease in invasive meningococcal disease (IMD) cases due to non-pharmaceutical interventions during the COVID-19 pandemic. This finding has raised concerns about a potential rebound of the disease due to an immunity gap. A seroprevalence study of individuals under 25 years old has provided evidence of a sharp decline in meningococcal serogroup B (MenB) serum bactericidal antibody (SBA) titres between 2019 and 2021.

Key Takeaways:

  • The proportion of individuals with a positive SBA titre decreased significantly between 2019 and 2021, from 2019 (63.4%) to 2020 (44.5%) and 2021 (33.2%).
  • Routine immunisation of infants resulted in a significant increase in SBA geometric mean titres (GMTs) in infants aged 6 to 24 months, compared to an age-matched population prior to the vaccine introduction.
  • SBA GMTs in infants aged 6 to 24 months were significantly higher in 2019 compared to pre-vaccine introduction data from 2001 to 2004.
  • The COVID-19 pandemic disrupted the routine immunisation schedule, but vaccine coverage was not significantly affected during the epidemiological year 2020 to 2021.
  • The study analyzed 1586 serum samples from the United Kingdom Health Security Agency (UKHSA) Seroepidemiology Unit (SEU), with 1371 valid titres obtained.
  • The research was conducted by Jennifer Louth and colleagues, and published in the journal Vaccine, 2025;63:127647.

Statistics:

  • 63.4% of individuals had a positive SBA titre in 2019.
  • Vaccine coverage was not significantly affected during the epidemiological year 2020 to 2021.
  • 44.5% of individuals had a positive SBA titre in 2020.
  • 33.2% of individuals had a positive SBA titre in 2021.
  • 1371 valid titres were obtained from the 1586 serum samples analyzed.
  • The study was conducted on 1586 serum samples from the United Kingdom Health Security Agency (UKHSA) Seroepidemiology Unit (SEU).

Sources:

  • Understanding the immunity gap for serogroup B invasive meningococcal disease due to non-pharmaceutical interventions during the Covid-19 pandemic. Vaccine, 2025;63:127647.
  • NewsRx. Reports on COVID-19 from Manchester Royal Infirmary Provide New Insights (Understanding the immunity gap for serogroup B invasive meningococcal disease due to non-pharmaceutical interventions during the Covid-19 pandemic). Vaccine Weekly. September 17, 2025; p 320.