Introduction
N. meningitidis serogroup B (MenB) has become the leading cause of meningococcal disease across several regions, including Europe and America. As compared to other vaccine-preventable diseases, the overall incidence is low, but it carries a substantial case fatality rate at 3-10%.¹ It results in significant morbidity and carries a threat for an outbreak.¹ Hence, vaccination against MenB has become an important public health priority.¹

Disease burden
Global
Invasive meningocccal disease (IMD) is a worldwide disease, but the epidemiology of the meningococcal capsular groups (Men) is unpredictable and varies by geographical regions and over time.² The annual global burden of IMD is estimated to be 1.2 million cases, with approximately 335,000 deathS.³

Canada
IMD continues to cause morbidity and mortality in children and adults in Canada despite the introduction of  conjugatevaccines.⁴ Serogroup B (MenB) IMD accounts for over 50% of Canadian cases and over 80% of cases in
children and adolescents <20 years of age.⁴ Article by Saboui et al. evaluated the IMD data from 2012-2019 in Canada and concluded that Serogroup B continues to account for the greatest proportion of disease.⁵

United States
Rates of meningococcal disease have declined in the United States since the 199o’.^6,7 In 2019, there were about 371 total cases of meningococcal disease reported.⁷ The CDC website highlighted the incidence rates (per 100,000
persons) of meningococcal disease caused by serogroup B compared to serogroups A, C, W, and Y by age group from 2010 to 2019 in the United States, where Serogroup B was responsible for approximately 60% of cases among children less than 5 years old.⁷

Inference
Despite the introduction of vaccines, IMD continues to cause morbidity and mortality in children and adults in Canada. Serogroup B accounts for more than 50% of cases of IMD.

References:

1. Rivero-Calle I, Raguindin PF, Gomez-Rial J, Rodriguez-Tenreiro C, Martinon-Torres F. Meningococcal Group B Vaccine For The Prevention Of Invasive Meningococcal Disease Caused By Neisseria meningitidis Serogroup B. Infect Drug Resist. 2019;12:3169-3188. Published 2019 Oct 9. doi:10.2147/IDR.S159952.
2. Pace D, Gauci C, Barbara C. The epidemiology of invasive meningococcal disease and the utility of vaccination in Malta. Eur J Clin Microbial Infect Dis. 2020;39(10):1885-1897. doi:10.1007/s10096-020-03914-8.
3. Badur S, Al Dabbagh MA, Shibi AM, et al. The Epidemiology of Invasive Meningococcal Disease in the Kingdom of Saudi Arabia: A Narrative Review with Updated Analysis. Infect Dis Ther. 2021;10(4):2035-2049. doi:10.1007/s40121-021-00467-x.
4. Bettinger JA, Liberator P, Halperin SA, et al. Estimated susceptibility of Canadian meningococcal B isolates to a meningococcal serogroup B vaccine (MenB-FHbp). Vaccine. 2020;38(8):2026-2033. doi:10.1016/j.vaccine.2019.12.051.
5. Saboui M, Tsang RSW, MacTavish R, et al. Epidemiology of invasive meningococcal disease in Canada, 2012-2019. Can Commun Dis Rep. 2022;48(5):228-36. https://doi.org/10.14745/ccdr.v48io5ao6.
6. Meningococcal Disease. https://www.cdc.gov/vaccines/pubs/pinkbook/mening.html#Epidemiology. Last accessed 16th July 2022.
7. Disease trends. https://www.cdc.gov/meningococcal/surveillance/index.html. Last accessed 16th July 2022.