ACUTE EPIGLOTTITIS AND INFANT CONJUGATE HAEMOPHILUS-INFLUENZAE TYPE-BVACCINATION IN NORTHERN FINLAND

Objective: To determine the incidence and characteristics of acute epi glottitis among children (less than or equal to 19 years of age) and a dults (greater than or equal to 20 years of age) before and after wide spread conjugate Haemophilus influenzae type b vaccination for infants . Design: A retrospective population-based survey over a 27-year perio d from 1967 through 1993 in 35 communities in a northern province of F inland with a population of approximately 300 000. Setting: An academi c tertiary referral center. Main Outcome Measures: All acute epiglotti tis cases in the area identified from the hospital discharge register and the regional autopsy register. Results: The average incidence rate for children was 1.8 cases per 100 000 individuals per year (95% conf idence interval [CI], 1.3 to 2.5). As no vaccine failures emerged, the incidence rate for children aged 0 to 4 years declined sharply once t he vaccination started in 1986 from 7.6 (95% CI, 5.3 to 10.4) to 0 (95 % CI, O to 3.3) cases per 100 000 individuals per year. By contrast, a fourfold increase in adult acute epiglottitis (incidence rate ratio, 4.6; 95% CI, 2.7 to 7.9) was detected after vaccination of the childre n, the average incidence rate for the whole period being 1.0 cases per 100 000 individuals per year (95% CI, 0.8 to 1.3). No marked change i n the adult patient profile was found during this increase, however. C onclusion: Acute epiglottitis practically vanished among young childre n in this population after conjugate H influenzae vaccination, but adu lt cases increased, the patient profile remaining the same.