Determinants of case fatality rates of meningococcal disease during outbreaks in Makkah, Saudi Arabia, 1987-97

We studied case-fatality rates (CFRs) among cases of meningococcal disease (MCD) admitted to Makkah (Saudi Arabia) hospitals during the period 1988-97. Of 483 cases, 431 (89.2%) were due to strains of serogroup A. 31 (6.4%) to serogroup W135, 16 (3.3%) to serogroup C, and 5 (1.0%) to serogroup B. Eighty-one patients died (case fatality rate (CFR)) 16.8%, 95% CI 13.5%, 20.4%). The CFR in infections due to serogroup A strains was 14.8%, and for other serogroups it was 32.7% (95% CI 20.3%, 47.1%). The CFR of MCD due to N. meningitidis serogroup A increased steadily with age (P < 0.05). Seeking first medical help at a foreign Hajj medical mission and being treated in a non-specialized hospital were associated with a higher case fatality rate.