Epidemiology of Haemophilus influenzae type b meningitis in Taiwan, 1997 and 2000.

In order to determine the incidence of Haemophilus influenzae type b (Hib) meningitis in Taiwan, we analyzed the National Health Insurance Research Database (NHIRD). We identified cases that were younger than 5 years old and diagnosed with Hib meningitis from the NHIRD in both 1997 and 2000. Sixteen and 8 children with Hib meningitis were identified in the NHIRD for 1997 and 2000, respectively. The majority of cases were 2 years old and under. The overall fatality rate was 8.33%. Assuming similar proportions of Hib meningitis in cases of meningitis with identified causes and meningitis without identified causes, the annual incidence of Hib meningitis in children younger than 5 years old was estimated to be 5.57 and 3.22 per 100,000 in years 1997 and 2000, respectively. The incidence of Hib meningitis in Taiwan is lower than in western countries and other Asian countries. This is consistent with the notion that Hib meningitis incidence is low in Chinese populations. The decline in incidence from 1997 to 2000 is likely a result of the introduction of a self-paid Hib vaccine in Taiwan, starting in 1993. The availability of the NHIRD provides an extra tool for the epidemiological study of infectious diseases in Taiwan and can be valuable for similar studies.