Haemophilus influenzae type B epiglottitis after immunization with HbOC conjugate vaccine

Abstract

Introduction: US Food and Drug Administration (USFDA) has licensed four Haemophilus influenzae type B (Hib) vaccines for use in children. Haemophilus influenzae type B is by far the most common pathogen in childhood epiglottitis and it is hoped that with the introduction of the Hib vaccine that a corresponding decrease in epiglottitis cases will be appreciated.

Materials and methods: A retrospective study of all children admitted with the diagnosis of epiglottitis for the 11-year period of 1982 to 1992 was conducted in order to determine the incidence of epiglottitis and Hib vaccine failure. Fifty-nine cases were included in the study by documentation of an inflamed epiglottis. The case of Hib epiglottitis in a 4-year-old child immunized with HbOC conjugate vaccine at 18 months of age is detailed.

Results: A statistically significant decrease was found in the incidence of epiglottitis since introduction of the vaccines; however, the overall trend in decrease for the 11-year period was not statistically significant. Vaccination status was difficult to accurately document with only two cases of vaccine failure identified.

Conclusion: The incidence of Haemophilus influenzae type B epiglottitis at our regional Children's hospital has decreased since the introduction of the Hib vaccine. Reasons for vaccine failure are postulated.