Meningococcal disease in developed countries usually consists of sporadic cases and small outbreaks. In contrast, massive epidemics of serogroup A or C meningococcal meningitis occur in tropical countries, most notably in sub-Saharan Africa. These seasonal outbreaks tend to occur during the dry season along a wide swath of equatorial Africa known as the “meningitis belt.”
The clinical presentation of epidemic meningitis is the same as in developed countries. Patients will typically present with fever, headache, nausea/vomiting, photophobia, and neck stiffness. Coma and death typically ensue if not treated. Diagnosis is with a spinal tap, although patients in resource-limited countries are often treated based on clinical grounds during a known outbreak. Mortality rates of less than 10% are obtainable. Large-scale vaccination programs are effective in decreasing spread of the disease within the affected areas and in adjacent population centers.
Management and Disposition
The mainstays of treatment are antibiotics and supportive care. Penicillins, cephalosporins, and ampicillin are still the treatments of choice in many settings and are usually efficacious.
Single-dose oily chloramphenicol injections have been used with success and allowed for easier management of large numbers in limited-resource settings. A 2nd dose is given in 24 hours if there has been no improvement.
Massive outbreaks of meningitis have occurred during the Hajj, a pilgrimage to Mecca in Saudi Arabia. They are the only country requiring proof of vaccination before entry.
An often-used critical threshold to define an epidemic in Africa is 15 cases per 100,000 population per week. This would be equal to over 1400 cases per week in the Chicago metropolitan area.
Both serogroup A and C are covered by the meningococcal vaccine recommended for travelers by the WHO and CDC.
Meningitis Spinal Fluid. CSF obtained from a 33-year-old Ugandan woman treated during an epidemic of serogroup A meningococcal meningitis. (Photo contributor: Seth W. Wright, MD.)
Meningitis in a Child with a Very Rigid Neck. Cerebral malaria should also be in the initial differential diagnosis. (Photo contributor: Richard P. Usatine, MD. Used with permission. From Usatine RP, Smith MA, Mayeaux EJ, Chumley HS. The Color Atlas of Family Medicine. 2nd ed. New York, NY: McGraw Hill; 2013: Fig. 7-14.)