A severe epidemic of meningococcal meningitis in Nigeria, 1996.

A particularly severe epidemic of meningococcal meningitis (cerebrospinal meningitis, CSM) occurred in Nigeria between January and June 1996. There were 109,580 recorded cases and 11,717 deaths, giving a case fatality rate of 10.7% overall. This is the most serious epidemic of CSM ever recorded in Nigeria, and may be the largest in Africa this century. It took over 3 months and the combined efforts of a National Task Force set up by the Federal Ministry of Health, the WHO, UNICEF, UNDP, Médecins Sans Frontières, the International Red Cross and several other non-governmental organizations to bring the epidemic under control. The main control measures centred on active treatment of infected persons, mass vaccination and health education. The exact number of persons treated cannot be ascertained, but there were treatment centres in almost every Local Government Area in the affected States. A study of 1577 patients admitted at the Infectious Diseases Hospital, Kano, showed that 84% of those infected were aged < or = 20 years and that, for the first time, infants aged < or = 2 months were affected. Despite intervention, the case fatality rate of 9.1% among this group of patients was similar to the nationwide figure of 10.7%. Long-acting oily chloramphenicol proved highly effective in the treatment of patients, and its routine use in epidemic CSM is recommended. Over 13 million persons were vaccinated in the course of the epidemic. For the first time, cases of CSM were reported from States south of the 'African meningitis belt', suggesting an extension of the belt. The severity of this epidemic yet again underscores the need for a clear policy regarding control measures aimed at forestalling future epidemics. The availability of the recently developed polysaccharide-protein conjugate vaccine should facilitate a decision on mass vaccination for the prevention of epidemic CSM in Africa.

Prognostic scores for use in African meningococcal epidemics.

Current WHO guidelines for the case management of meningococcal infections during epidemics in developing countries often cannot be applied, largely because of the limited health resources in such countries. Several scoring scales based on clinical and laboratory features in numerous combinations have been developed for the management of meningococcal infections in developed countries, and these have facilitated early identification of patients with fulminant disease and thus early intervention and reduction in mortality. Unfortunately such scoring scales are not appropriate for use in developing countries. We identified hypotension, tachycardia, tachypnoea, delay in capillary refill time, coma, absence of neck stiffness and petechiae and/or purpura as simple prognostic factors of meningococcal disease. Two scores were developed: score I, which includes all seven prognostic factors, had a sensitivity and specificity of 80% and 94%, respectively. Score II, which excluded hypotension, had a sensitivity and specificity of 73.3% and 89.7%, respectively. Quick and simple scoring scales are therefore not only applicable but useful for the case management of patients in meningococcal epidemics in developing countries.