Meningococcal disease incidence and mortality in Wisconsin, 1993-2002

Neisseria meningitidis is a major cause of sepsis and meningitis in children and young adults in the United States. To examine recent epidemiologic features of meningococcal disease in Wisconsin, we evaluated Wisconsin case surveillance data collected during 1993-2002. Surveillance data for cases with onsets during this time were analyzed; statistical trends were assessed. Mortality was examined with regard to age, sex, serogroup, college student status, and young adult status by unadjusted and adjusted analyses. During 1993-2002, 462 cases of meningococcal disease were reported in Wisconsin; 55% of case patients were aged < 19 years. The annual incidence was 0.9 cases per 100,000 persons per year, and incidence was highest among children aged <2 years. Two seasonal peaks in cases were observed during January-April and September-October. The annual mortality rate during the 10-year interval was 0.09 deaths per 100,000 persons per year. Adjusted analysis indicated that serogroup C infection, young adult, and college student status (but not sex) were associated with mortality. Meningococcal disease remains uncommon and sporadic in Wisconsin. Incidence and mortality rates are highest among young children, but young adults who acquire the disease appear to be at an increased mortality risk.