Autumn asthma peak driven by kids and colds
A Canadian study provides more evidence that the spike in hospitalizations for asthma that comes around every September is closely related to children returning to the classroom after summer vacation—because they catch viruses there that are known to exacerbate asthma, and share them with younger siblings and parents.
“The bottom line,” Neil Johnston from Ontario said, “is that asthmatics, especially those exposed to children, may be at high risk for worsening asthma symptoms following return to school after the summer vacation. They should be prepared for this,” he said, “by having and taking asthma control medications before and during this period.”
Johnston and colleagues analyzed Canadian asthma hospital admission data over a 13-year period. Their goals were to better understand the sequence of timing of September asthma hospitalization epidemics in children and adults and determine whether school-age children transmit agents that cause these epidemics.
For each year analyzed, the September peak in asthma hospitalizations occurred in school-age children an average of 17.7 days after kids went back to school, the investigators report in the Journal of Allergy and Clinical Immunology. In preschoolers, the peak occurred 1.7 days later, and in adults 6.3 days later than in school-age kids.
“The key findings are that the September epidemic of asthma occurs first and most strongly in children and later in adults and that its occurrence is directly related to school return,” said Johnston, who is with the Firestone Institute for Respiratory Health in Hamilton.
“We know from previous work that the great majority of asthma exacerbations in children coincide with rhinovirus infections and that these are most common during September and October,” Johnston explained. Therefore, it seems likely that agents provoking asthma exacerbations may be transferred during the September epidemic from school-age children to preschoolers to adults.
This scenario is not unique to Canada. A paper set to be published soon shows this effect in other countries as well, Johnston said.
SOURCE: Journal of Allergy and Clinical Immunology, March 2006.
Tell-a-Friend comments powered by Disqus