Children with asthma not at increased risk for SARS-CoV-2 infection, study finds

In a new study published in Pediatrics, researchers concluded that children with asthma have similar risk for for SARS-CoV-2 infection compared with children without asthma.

“We found no evidence that children with asthma are at higher risk of COVID-19 or of developing severe illness from COVID-19,” Matthew Kelly, MD, MPH, associate professor of pediatrics and global health, associate program director of the Pediatric Infectious Diseases Fellowship and associate director of physician-scientist development in the Office of Pediatric Education at Duke University School of Medicine in Durham, North Carolina, told Healio.

Kelly and colleagues conducted a retrospective cohort study that included 46,900 children aged 5 to 17 years in the Duke University Health System with a Durham County, North Carolina, residential address. Children with asthma were classified using previously validated electronic health record-based definitions, and SARS-CoV-2 infections were identified via positive polymerase chain reaction testing of samples collected from March 2020 to September 2021. Children with asthma were matched to those without asthma.

“Because severe asthma exacerbations are often associated with respiratory virus infections, there has been concern that children with asthma who acquire SARS-CoV-2 might be at high risk for severe illness,” Kelly told Healio. “However, we and others had seen relatively few children with SARS-CoV-2 infections hospitalized with asthma exacerbations; moreover, there were some data to suggest that asthma, or the inhaled corticosteroids commonly prescribed to children with asthma, might lower the risk of acquiring SARS-CoV-2.”

Overall, 13.5% of children had asthma (median age, 11 years; 58% boys). Twenty-two percent of all children had one or more SARS-CoV-2 tests during the study period. The propensity score-matched cohort included 12,648 children, half of whom had asthma and half did not.

Children with asthma had a higher likelihood of testing positive for SARS-CoV-2 infection compared with children without asthma (33% vs. 20.9%; P < .0001).

In the propensity score-matched cohort, 5.6% of children tested positive for SARS-CoV-2; this included 2.8% of children with asthma and 2.8% of children without asthma (RR = 0.98; 95% CI, 0.85-1.13).

Researchers reported similar risk for SARS-CoV-2 infection among children with asthma who were prescribed inhaled corticosteroids (RR = 0.88; 95% CI, 0.73-0.94) and children without an inhaled corticosteroid prescription (RR = 1.08; 95% CI, 0.89-1.34). There was also no difference in risk for infection among children with a history of severe asthma exacerbations (RR = 0.95; 95% CI, 0.71-1.25) and children with comorbid atopic disease (RR = 0.94; 95% CI, 0.79-1.12), according to the results.

One child with asthma and seven children without asthma required hospitalization for SARS-CoV-2 infection during the study period.

“We still know very little about the immunological or biological factors that contribute to the low disease severity of SARS-CoV-2 infection among children, including children with asthma. Understanding the mechanisms underlying these age-related differences in disease severity has the potential to inform future development of novel SARS-CoV-2 vaccines or therapeutics,” Kelly said. “More broadly, we need more information regarding the potential effects of severe COVID-19 and multisystem inflammatory syndrome in children (MIS-C) on the long-term health of children.”

For more information:

Matthew Kelly, MD, MPH, can be reached at matthew.kelly@duke.edu.