Effects of Respiratory Syncytial Virus Infection in Infancy on Asthma and Respiratory Allergy in 6-Year-Old Children.

OBJECTIVE: The purpose of this study was to examine the association between respiratory syncytial virus (RSV) infection in early infancy and health conditions such as asthma and respiratory allergies at 6 years of age in a cohort of US children born at term with no medical issues at birth.

METHODS: Data (1542 records) from the Infant Feeding Practices Study II and the Year Six Follow-Up study were used in the analysis. Descriptive statistics and logistic regression were conducted to estimate the magnitude and direction of potential associations between children's health conditions such as asthma, hay fever, or respiratory allergy, and RSV infection during infancy.

RESULTS: A substantial proportion of children with RSV infection in infancy were reported to have developed asthma (10.3%) and hay fever or respiratory allergy (9.4%) by 6 years of age. Analyses revealed that children with RSV infection in infancy were more likely to develop asthma (odds ratio 1.99, 95% confidence interval 1.06-3.74), and hay fever or respiratory allergy (odds ratio 2.13, 95% confidence interval 1.28-3.57) by 6 years of age. In addition, the risk of developing asthma and hay fever or respiratory allergy by 6 years of age increased considerably with a family history of these conditions.

CONCLUSIONS: Our findings support the need for understanding and monitoring the long-term health outcomes of RSV infection in infancy. Appropriate prevention and treatment measures for RSV infection during infancy may reduce the incidence of associated long-term adverse health outcomes. Knowledge of the long-term complications of RSV infection in infancy, such as asthma, hay fever, or respiratory allergy, can aid in the prevention and better management of these health conditions.