Global Meningitis Incidence and Mortality Rates Have Decreased Since 1990

A large portion of incident and mortality rates for meningitis lies among children younger than age 5, according to study findings published in the journal Lancet Neurology. 

The World Health Organization (WHO) set a goal to reduce global meningitis cases by 2030. Researchers conducted a study to determine the patient factors associated with the incident cases and deaths related to acute infectious meningitis. 

Data was collected from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. This database reports estimates of meningitis mortality by age and sex from 1990 through 2019. Results were reported based on the social demographic index (SDI), which is a composite indicator based on income per capita, years of education, and total fertility. 

Mortality estimates for meningitis were based on data that comprised a total of 24,726 site-years. Data to conduct mortality estimates were collected from vital registration, verbal autopsy, minimally invasive tissue sampling from the Child Health and Mortality Prevention Surveillance (CHAMPS), and epidemiologic databases. 

The researchers made morbidity estimations using studies from systematic reviews, surveillance data, cause-specific meningitis mortality estimates, claims data, and inpatient data. Across all age groups, a total of 2.51 million (95% uncertainty interval [UI], 2.11-2.99) new meningitis cases were documented globally in 2019. Of these cases, 1.28 million (95% UI, 0.947-1.71) were reported in children younger than age 5. 

The global, age-standardized meningitis incidence rate was 35.4 (95% UI, 29.6-42.5) cases per 100,000 population. The mortality rates decreased from 1990 (7.5; 95%UI, 6.6-8.4 per 100,000 population in 1990) to 2019 (3.3; 95%UI, 2.8-3.9 per 100,000 population).

The estimated global deaths were 236,000 in 2019 (95% UI, 204,000-277,000). The meningitis burden was highest among children younger than age 5, with 112,00 deaths estimated (95% UI, 87,400-145,000).

Across all age groups, the bacteria that contributed to the highest proportion of meningitis deaths in 2019 was S pneumoniae (18.1%; 95% UI, 17.1-19.2). Other bacteria groups associated with meningitis deaths were N meningitidis (13.6%; UI, 12.7-14.4) and K pneumoniae (12.2%; 95% UI, 10.2-14.3). 

From 1990 to 2019, the largest reduction in the number of deaths among children younger than age 5 was reported for H influenzae (76.5%; 95% UI, 69.5-81.8), N meningitidis (72.3%; 95% CI, 64.4-78.5), and viruses (58.2%; 95% UI, 47.1-67.3).

“[M]ore meningitis-related deaths might be prevented by quickly scaling up immunization and expanding access to health services,” the researchers concluded. “Further reduction in the global meningitis burden should be possible through low-cost multivalent vaccines, increased access to accurate and rapid diagnostic assays, enhanced surveillance, and early treatment.”

Study limitations are data availability and quality, some studies with differing definitions of meningitis, and some meningitis cases being excluded. 

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.