ABSTRACT
This chapter focuses on the understanding of how respiratory viruses may contribute to asthma inception and asthma exacerbations, as well as identify areas in need of further study. While most research into the relationship between viruses and the development of asthma has focused on viral infections in early childhood, a few studies have investigated whether antenatal viruses predispose the children to developing wheezing or asthma. Respiratory viruses have been associated with asthma exacerbations. With the advent of molecular techniques to identify viruses, viruses have been detected in approximately 80%–85% of wheezing episodes in school-age children, and in approximately 50%–75% of acute wheezing episodes in adults. A growing body of evidence suggests that respiratory viruses interact with atopic responses in asthma exacerbations. Sensitization and exposure to high levels of the relevant allergen increase the risk of exacerbations when atopic asthmatics develop rhinovirus infections.
