Research and analysis

Laboratory confirmed cases of invasive meningococcal infection in England: April to June 2024

Updated 28 November 2024

Applies to England

In England, the national UK Health Security Agency (UKHSA) Meningococcal Reference Unit (MRU) confirmed 92 cases of invasive meningococcal disease (IMD) between April and June 2024.

Case numbers were similar to the 86 confirmed in the equivalent period in 2023 (table 1). Case numbers were lower than the 122 cases in the equivalent period in 2019, before pandemic restrictions were implemented in the UK. Cases in the intervening years – impacted by COVID-19 population control measures (1) – were very low, with 29, 17 and 55 confirmed in the equivalent periods in 2020, 2021 and 2022, respectively.

Earlier reports on IMD cases in England are available: Meningococcal disease: guidance, data and analysis

Following the complete withdrawal of COVID-19 containment measures in England from July 2021, overall case numbers returned to pre-pandemic levels driven mainly by group B meningococcal disease (MenB). Cases due to the other capsular groups remained very low because of the highly effective indirect (herd) protection provided by the adolescent meningococcal ACWY (MenACWY) conjugate vaccine programme introduced from August 2015, alongside direct protection in those vaccinated (2).

The distribution of meningococcal cases by capsular group causing IMD between April and June 2024 is summarised in table 1. MenB accounted for 83.7% of all cases (77 of 92), followed by MenW: 14.1% (13 cases), MenY: 1.1% (1 case), and MenC: 1.1% (1 case). There were no confirmed cases for any other capsular groups. Several MenW cases were known to have had recent travel to the Middle East, with similar cases also identified in France and the United States of America (3).

There were 77 MenB cases confirmed between between April and June 2024, compared to 72 cases in the corresponding period in 2023. Between April and June 2024, MenB was responsible for 100% of IMD cases in individuals under 25 years of age and 66.7% of cases in individuals aged 25 years or older (table 2). All confirmed cases of MenW, MenY and MenC occurred in individuals aged over 25 years.

The latest vaccine coverage information is available at Vaccine uptake guidance and the latest coverage data.

Table 1. Invasive meningococcal disease in England by capsular group and laboratory testing method: April to June only, 2023 and 2024

Capsular groups
[note 1]
Culture and PCR (2023) Culture and PCR (2024) Culture only (2023) Culture only (2024) PCR only (2023) PCR only (2024) Total (2023) Total (2024)
B 11   14     21     27     40     36     72     77
C –   –     1     1     2     –     3     1
Ungrouped/ungroupable
[note 2]
 –   –     1     –     –     –     1     –
W 1   3     4     10     –     –     5     13
Y –   –     4     1     1     –     5     1
Total 12   17     31     39     43     36     86     92

Note 1: No cases of group A, E, X or Z were confirmed during the periods summarised in the table.

Note 2: Ungrouped or ungroupable refers to invasive clinical meningococcal isolates that were non-groupable, while ‘ungrouped’ cases refers to culture-negative but PCR screen (ctrA) positive and negative for the four genogroups (B, C, W and Y) routinely tested for.

Table 2. Invasive meningococcal disease in England by capsular group [note 1] and age group at diagnosis: April to June 2023

Age groups Capsular group B Capsular group C Capsular group W Capsular group Y Capsular group ‘Other’
[note 2]
Total number Total percentage
<1 year 5 5 5.4%
1 to 4 years 15 15 16.3%
5 to 9 years 4 4 4.3%
10 to 14 years 6 6 6.5%
15 to 19 years 12 12 13%
20 to 24 years 5 5 5.4%
25 to 44 years 6 4 10 10.9%
45 to 64 years 11 1 4 16 17.4%
65+ years 13 5 1 19 20.7%
Total 77 1 13 1 92 100%

Note 1: No cases of group A, C, E, X, Y or Z were confirmed during the period summarised in the table.

Note 2: Ungrouped or ungroupable refers to invasive clinical meningococcal isolates that were non-groupable, while ‘ungrouped’ cases refers to culture-negative but PCR screen (ctrA) positive and negative for the four genogroups (B, C, W and Y) routinely tested for.

References

1. Subbarao S, Campbell H, Ribeiro S, Clark SA, Lucidarme J and others (2021). ‘Invasive meningococcal disease, 2011 to 2020, and impact of the COVID-19 pandemic, England’. Emerging Infectious Diseases: volume 27, number9, pages 2,495 to 2,497.

2. Campbell H and others (2022). ‘Impact of an adolescent meningococcal ACWY immunisation programme to control a national outbreak of group W meningococcal disease in England: a national surveillance and modelling study’ Lancet Child Adolescent Health: volume 6, issue 2

3. Vachon MS, Barret AS, Lucidarme J, Neatherlin J, Rubis AB, Howie RL and others (2024). ‘Cases of meningococcal disease associated with travel to Saudi Arabia for Umrah pilgrimage - US, UK and France, 2024’. Morbidity and Mortality Weekly Report: volume 73, number 22, pages 514 to 516