Asthma has a striking temporal character, in which time-of-day, patient age, and season each influence disease activity. The extent to which rhythms in asthma activity reflect exposure to specific disease triggers remains unclear. In this study, we examined how virus mitigation strategies enacted during the COVID-19 pandemic (“lockdown measures”) affected rhythms in asthma clinical activity in children. To this end, we retrospectively analyzed asthma clinical presentations in children <18 years old to our regional academic medical center, comparing 4 years of medical records prior to COVID-19 lockdown measures to the 12 months immediately after the institution of such measures. We correlated these data to positive viral test results, febrile seizures, and allergic clinical surrogates (allergic reaction visits, and ED antihistamine prescriptions, respectively) over the same timeframe. In the 12 months following the institution of COVID-19 lockdown, positivity rates for common respiratory viruses dropped by 70.2% and ED visits for asthma among children dropped by 62% compared to pre-COVID years. Lockdown suppressed seasonal variation in positive viral tests and asthma ED visits, while diurnal rhythms in asthma visits was unchanged. Asthma seasonality correlated most strongly with rhinovirus positivity both before and after the institution of COVID lockdown measures. Altogether, our data supports a causal role for viruses in driving seasonal variability in asthma exacerbations in children.
【저자키워드】 COVID-19, viruses, Asthma, seasonality, Biological Rhythms,