The most dangerous times of year for children with asthma are soon after their schools reopen after a break, and a new study from UT Austin finds that cold viruses are largely to blame.
Health experts have observed that children with asthma tend to have the worst symptoms at the same times each year — when school starts in the fall and after extended breaks, such as spring break. Researchers previously thought environmental factors such as air quality might be to blame, but the new study confirms that the the prevalence of common colds leads to seasonal waves of worsening asthma symptoms.
Authors of the study speculate that when children are out of school, they tend to spend less time with other children and are exposed to fewer viruses. As a result, their viral immunity decreases. When they return to school, they are exposed to viruses at much higher rates, and this is also the time when they are most susceptible.
Worsening asthma symptoms result in millions of missed work and school days and $50 billion in direct health care costs in the U.S. each year.
“The school calendar predicts common cold transmission, and the common cold predicts asthma exacerbations,” says Lauren Meyers, professor of integrative biology and statistics and data sciences at The University of Texas at Austin and senior author of the study. “This study provides a quantitative relationship between those things.”