The epidemiology of acute epiglottitis in children in Western Australia.

A comprehensive case definition was used to study all cases of epiglottitis that occurred in children under 15 years of age in Western Australia during a 5 year period. There was microbiological evidence of Haemophilus influenzae type b infection in 71% of 103 cases of epiglottitis. Seventy-five per cent of cases occurred in children under 5 years of age. In this age group, the estimated annual incidence (13.5 episodes per 100,000) was significantly lower than that reported in Victoria (22.7 per 100,000). The case definition of invasive H. influenzae type b disease used for surveillance purposes in Canada was more sensitive than the definitions used in the United States or England and Wales, yet even the Canadian definition could have detected only 65% of the cases of epiglottitis that occurred in Western Australia. A simple and sensitive surveillance system which could be used to monitor the impact of H. influenzae type b immunization in Western Australia is proposed.