During the pandemic, lockdowns used to curb the spread of Covid-19 also led to a decline in other infectious diseases. Meningitis rates were at a historic low until September last year.
Since then, however, there has been an increase in MenB cases among adolescents and young adults in England, ‘particularly in university students’.
Exceeding pre-pandemic levels
The report, An Increase in Group B Invasive Meningococcal Disease Among Adolescents and Young Adults in England Following Easing of COVID-19 Containment Measures, says that: “Between September and November 2021, invasive meningococcal disease (IMD) cases increased with group B disease in adolescents/young adults rising sharply and exceeding pre-pandemic levels.”
During September-November 2021, 41.5% of IMD cases occurred among 15 to 19-year-olds, compared to 11.8% and 14.3% during the same period in 2018 and 2019, respectively. Importantly, the number of IMD cases in this age-group during this period in 2021 (22) was higher than the corresponding periods in 2018 (16) and 2019 (19).
Of the IMD cases confirmed among the 15 to 19 and 20 to 24-year-old age groups in September to November 2021, 84.6% (22/26) were students registered at a further or higher education institution.
Among all adult age groups (19 years old and over), group B IMD cases increased in relation to the same period in 2020, although the number of cases remained substantially lower than the corresponding figures observed in 2018 and 2019.
Figures in infants and children
The number of group B IMD cases in infants (under 1 year old) in 2021 was higher than in 2020 and almost reached the number seen in the same period of 2019. Among 1 to 4 and 5 to 9-year-olds, IMD cases remained similar or lower than 2020 levels and substantially lower than the corresponding period in 2018 and 2019.
Despite the increase in group B disease in late 2021, the number of group W, Y and C cases remained very low. This is likely to be due to the MenACWY vaccine programme introduced for adolescents as part of the UK national immunisation programme in 2015, the report adds.
Our chief executive, Dr Tom Nutt, said: “We always feared there might be a rebound against the historically low figures for meningococcal infection we have been seeing during the pandemic, whilst hoping there would not be. This report suggests this is happening and we will keep a close eye on the situation as it develops.
Spreading awareness messages
“At the same time, we are already working hard to spread awareness messages within universities, through working collaboratively with UKHSA on their current campaign, as well as through our own contacts and in partnership with other charities, vaccine manufacturers and pharmacists.
“With teenagers and young people being far more likely to carry the bacteria that can cause meningococcal disease and as most students will not have been vaccinated against MenB it is vital they remain extra vigilant, know the signs and symptoms and seek urgent medical advice if they or one of their friends becomes ill.”
The paper suggests the rise in cases may be because of a combination of factors including high levels of transmission in young people, and an “immunity debt”, sparked by the fact that lockdowns reduced the opportunities for meningococcal exposure and transmission among adolescents.
Prof Ray Borrow, one of the paper’s authors and head of the vaccine evaluation unit at the UKHSA, told the Guardian newspaper: “Whilst this is early data, it is crucial we continue to monitor all strains of invasive meningococcal disease given the impact social distancing and other Covid responses have had in limiting natural circulation, blocking both the benefits and harms of exposure to these bacteria, which can lead to a lack of immune stimulation within the population.”
Read the full UKHSA report here.