From the Guidelines
Epidemic meningitis is typically seasonal, occurring during the dry season in certain regions, such as the "meningitis belt" in sub-Saharan Africa, which spans from Senegal to Ethiopia 1.
Characteristics of Epidemic Meningitis
- Geographic distribution: Epidemics of meningococcal disease are recurrent in the "meningitis belt" of sub-Saharan Africa, which extends from Senegal in the West to Ethiopia in the East 1
- Seasonality: Epidemics in the meningitis belt usually occur during the dry season, from December to June 1
- Incidence rate: An average incidence rate of disease that exceeded 15 cases/100,000/week for a period of 2 consecutive weeks was predictive of an epidemic 1
Identification and Control
- Outbreak identification: Early priority should be given to the determination of etiology and serogroup, which may be accomplished through the use of latex agglutination tests 1
- Antibiotic resistance patterns: It is also important to determine antibiotic resistance patterns to guide treatment and control efforts 1
From the Research
Characteristics of Epidemic Meningitis
- Epidemic meningococcal meningitis is a major health problem in sub-Saharan Africa, accounting for thousands of deaths and causing morbidity in hundreds of thousands of people 2
- The disease is caused by Neisseria meningitidis, with serogroup A being responsible for the largest and most recent epidemics in Africa 2
- The age group at highest risk of disease is typically 6 months-30 years old, although recent epidemics have seen high age-specific attack rates in those aged 30 years and over 2
- Epidemic meningitis is characterized by a high incidence rate, with the WHO proposing a cutoff of 15 cases/100,000/week averaged over two weeks for early detection of an emerging epidemic 2
- The disease can spread quickly, with person-to-person transmission occurring through inhalation of droplets of infected nasopharyngeal secretions by direct or indirect oral contact 3
- Epidemic meningitis can have a high mortality rate, with overall mortality due to meningitis usually around 10 per cent, and case fatality rates exceeding 50 per cent in cases of meningococcal septicemia 3
Geographic Distribution
- Epidemic meningococcal meningitis is primarily found in the "meningitis belt" of sub-Saharan Africa, which includes countries such as Guinea-Bissau, Guinea, Côte d'Ivoire, Togo, and others 2, 4
- The disease can also occur in other parts of Africa, as well as in other regions of the world, including Asia and the Americas 4, 5
Prevention and Control
- Prevention and control strategies for epidemic meningitis include vaccination, chemoprophylaxis, and early detection and treatment 5, 3
- Mass vaccination campaigns can be effective in halting an epidemic of meningococcal disease due to serogroup A or C 3
- Public health approaches to outbreaks of meningococcal meningitis include early detection, confirmation of the epidemic, and implementation of control measures such as vaccination and chemoprophylaxis 2, 3