Upper airway infections in preschool children-frequency and risk factors

Abstract
Objective - To estimate the frequency of upper respiratory tract infections (URTI) over a three month period and possible risk factors in the social surroundings, daily routines and health history. Design - A retrospective epidemiological survey by means of questionnaires. Setting - Gardabaer, a small town, ten km south of Reykjavik, Iceland. Participants - All children in Gardabaer, six months to six years old (n = 555). Main outcome measure - Number of URTI and possible risk factors. Results - The response rate was 81.8%. The most common infections were common cold (n=345), acute otitis media (n=82), sore throat (n=75), and bronchitis (n=13). The mean frequency of URTI during the previous three months was 2.2 in boys and 1.7 in girls (p < 0.01). Log-linear regression analysis showed that the predicted number of URTI was 1.9 higher if the child was attending day care, and that the number of URTI increased by 1.015 with each month until the age of 24 months, but decreased after that by 0.985. Conclusions - The major factors which affect the frequency of URTI are: age, sex, family history of frequent URTI, asthma, allergy, and the form of day care. Measures to reduce URTI could involve prospective intervention studies on the form of day care.