Meningococcal disease in Auckland, July 1992-June 1994

Aims. To assess two years of meningococcal disease in the Auckland area, th e outcomes and management issues, and the specific socio-geographic groups that are affected. Methods. Using the nationally agreed case definition, a retrospective chart review was undertaken. Case finding was through the National surveillance system at ESR, backed by hospital laboratory and coroner case findings. Results. There were 106 cases of meningococcal disease, both adult and paed iatric, from July 1992 to June 1994. Group B (n=61), was predominant throug hout this period especially in the winter months. There were two main age g roups most affected. The first, and most striking, was in Maori and New Zea land Pacific Island children younger than five years, with rates of 52.6 an d 54.2/100 000 respectively. The second peak was in European, and to a less er extent Maori, 15-24 year-olds, (rates 11.7 and 8.5/100 000, respectively ). The annual incidence was 5.6/100 000 with an overall case fatality rate of 6.6%, (n=7). South Auckland had the greatest proportion of cases with 42 /106. Two-thirds of the cases were referred for hospital admission by a gen eral practitioner. From both general practitioner and self-referred groups, two-thirds had a petechial/purpuric rash on arrival at hospital. For gener al practitioner referred cases, 24 received parenteral antibiotics on refer ral, and from these cases there was one death, (1/24). Those not treated wi th antibiotics (general practitioner or self-referred) had a mortality of 2 /41. There were 31 cases of paediatric meningococcal meningitis. Nineteen c ases had dexamethasone in appropriate dose and timing; no hearing loss occu rred in the 17 cases that survived (0/17), compared to 2/12 not treated wit h dexamethasone. This compares to a published rate of 5-7%. Conclusions. Meningococcal disease, predominantly serogroup B, is of high i ncidence in Auckland. The highest rates of disease are occurring in the und er five-year-olds, where an effective group B vaccine is awaited. The benef it of dexamethasone is suggestive. There was no clear benefit in outcome by pre-treatment with parenteral antibiotics for paediatric meningococcal dis ease though no suggestive detrimental effect either.