Infant vaccinations and childhood asthma among full-term infants

Purpose To determine if infant vaccinations are associated with childhood asthma among full-term infants. The secondary objective was to describe relationships between characteristics of infant wheezing and childhood asthma. Methods We used baseline data from a study of infant wheezing that selected full-term infants born into a health maintenance organization (HMO) during 1991–1994, continuously enrolled for at least 12 months and without perinatal pulmonary or other selected conditions. Information had been abstracted for infancy (0–18 months) regarding wheezing, vaccinations and asthma risk factors. Using automated data, we identified asthma cases in 1998 among those enrolled for at least 6 months during the year. Results A total of 1778 full-term infants met our study criterion and 9% had asthma in 1998. Childhood asthma was not significantly associated with having received Hepatitis B vaccine or age at first Hepatitis B vaccine; number of whole-cell pertussis, Haemophilis influenzae type b or oral polio vaccine doses; having received measles, mumps, rubella vaccine; or total number of vaccine doses combined. Childhood asthma was significantly associated with number of infant wheezing episodes. Conclusions Our findings do not support concerns that vaccines are associated with increased risk of asthma but confirm that frequency of infant wheezing is associated with childhood asthma. Copyright © 2003 John Wiley & Sons, Ltd.