Early-life respiratory viral infections, atopic sensitization, and risk of subsequent development of persistent asthma

This study suggests that severe viral infections combined with sensitivity to allergies during the first year of a child's life may lead to the development of asthma later in childhood. The researchers studied almost 200 children for 5 years, recording the viruses they were infected with during their first year of life and when they developed allergies. They found that those children who had a lower respiratory viral infection during their first year of life and developed sensitivity to an allergen before they were two were three to four times more likely to suffer from asthma at the age of 5. Journal of Allergy and Clinical Immunology 2007.