Incidence of Haemophilus influenzae Type b Meningitis Among Children Less Than 5 Years of Age in Slovakia

Owing partly to a lack of disease burden data, Eastern and Central European countries have not introduced universal infant immunization against Haemophilus influenzae type b. To determine the incidence of Haemophilus influenzae type b meningitis among children less than 5 years of age, data were examined from eight districts in Slovakia that formed part of a national Haemophilus influenzae type b surveillance system. All invasive isolates of Haemophilus influenzae type b identified from these districts during 24 months (1996–1997) were sent to a single central laboratory for serotype confirmation. Thirty-five cases of confirmed Haemophilus influenzae type b meningitis were identified, for a disease incidence among children under 5 years of 17.3 per 100 000 population per year. Only 13 cases were identified during 1996, the first full year of the surveillance system. Records were available for review at six of the eight district laboratories and showed that, using World Health Organization definitions, almost half of the cases of probable bacterial meningitis were culture negative, suggesting that the true incidence of Haemophilus influenzae type b meningitis may be considerably higher than 17.3. The rate of Haemophilus influenzae type b meningitis among children less than 5 years of age in Slovakia is comparable to that found in Western Europe and North America during the pre-vaccine era. Thus, universal, publicly funded infant vaccination in Slovakia can be expected to have the same dramatic effect on Haemophilus influenzae type b disease morbidity and mortality as has been demonstrated in other countries that have adopted this approach.