Etiology and Mortality of Bacterial Meningitis in Northeastern Brazil

Little is known of the current incidence and mortality of meningitis in developing nations, especially in Latin America. We reviewed all cases of meningitis in an isolation-fever hospital in Salvador, Brazil, for the decade 1973-1982. Of all admissions, 6,751 (27%) were for meningitis; 4,100 (61%) of these cases were of definite or probable bacterial etiology. Children younger than 15 years accounted for 79% of cases, and 45% of cases were in children under 2 years. The overall case fatality rate was 33%, with 50% of these deaths occurring within 48 hours of hospitalization. Neisseria meningitidis was the etiologic agent in 32% of the cases, with a case fatality rate of 14%. Epidemics caused by N. meningitidis group C, then group A, in 1974-1978 accounted for 60% of the cases. Streptococcus pneumoniae caused 17% of cases, with a case fatality rate of 59%. Haemophilus influenzae type b, the most common cause of nonepidemic meningitis, caused 23% of all cases, with a case fatality rate of 38%. Enterobacteriaceae were the etiology in only 3.6% of patients, but the case fatality rate was 86%. Cultures were negative in 18% of cases with purulent cerebrospinal fluid. A total of 84% of H. influenzae, 40% of S. pneumoniae, 78% of Enterobacteriaceae, and 15% of N. meningitidis cases occurred in children less than 2 years of age. Case fatality rates were highest in this group. Vaccines protective for this age group are urgently needed.