We reviewed charts of 261 children seen at Children's Hospital of Wisconsin from 1957 to 1987 with culture-proven meningococcemia or meningococcal meningitis, and we analyzed trends in mortality and disease severity for that interval. Overall case fatality was 10%, ranging from 9% in the period 1957 to 1963, to 16% in the period 1980 to 1987 (P = 0.15). The percent of patients admitted with severe disease increased from 14% to 38% (P = 0.001). When stratified by disease severity, case-fatality rates did not change with time. We conclude that technologic advances of the past 30 years had no measurable impact on mortality from meningococcal infection in our hospital and that crude case-fatality rates can be misleading if disease severity is not considered.