Association of meningococcal serogroups with the course of disease in the Netherlands, 1959-83.

To study the association of meningococcal serogroups with the course of disease, we reviewed the case histories of 1221 patients. The meningococci from these patients constituted a sample from isolates collected and serogrouped systematically in the Netherlands since 1959. Of these 1221 isolates, 64% were serogroup B. The overall case fatality rate was 5.1%, and the rate was lowest for patients with serogroup A infections (2.3%) and highest for serogroup W135 (18%) (P < 0.01). The occurrence of septicaemia without meningitis (case fatality rate 15.3%) was similarly distributed among the serogroups (A, 4.0%; W135, 30%). Sequelae occurred in 7.9% of patients (loss of hearing, 3.2%) and were remarkably prevalent after disease due to minor serogroups (X and Y: 4 out of 12). In a log-linear analysis, both age and serogroup were significantly associated with case fatality rate and with the occurrence of septicaemia and sequelae. It is argued that these data are representative, despite the problems inherent in a retrospective investigation. The course and outcome of meningococcal disease appear to be related to the Neisseria meningitidis serogroup and to host factors.