A large spike in cases of respiratory syncytial virus (RSV) among young children has been a nationwide health problem over the past several months. Although the winter “RSV season” has now ended, a new study by Vanderbilt University Medical Center researchers may raise new concerns among parents. It found that being infected with RSV during the first year of life significantly raises a child’s risk of developing asthma.
The study, called INSPIRE (Infant Susceptibility to Pulmonary Infections and Asthma Following RSV Exposure) included about 2,000 healthy infants who were 6 months old or younger during the prime season for RSV infection – November to March – in the university’s home state of Tennessee. These babies were tested biweekly to determine whether they were infected with RSV during their first year of life, which was the case for 54% of them.
The children were then followed annually, and all were evaluated for asthma when they reached age 5. Overall, those who had been infected with RSV before their first birthdays had a 26% higher risk of asthma, while infection with RSV after age 1 did not produce the same increase in asthma risk.
“We believe that when a child is infected with RSV in the first year of life, when the lungs and immune system are still under development, that could lead to certain abnormalities that can later cause asthma,” said Christian Rosas-Salazar, M.D., MPH, assistant professor of Pediatrics at Vanderbilt and the study’s first author.
He expressed hope that the results of this study, published in the journal The Lancet, will motivate public interest in ongoing trials of RSV vaccines, as well as in treatments like monoclonal antibodies which can decrease the severity of RSV infection in the very young.
Those vaccines finally appear to be close at hand after decades of efforts. On May 3, the FDA cleared a vaccine for adults 60 and older developed by GlaxoSmithKline, which will be sold under the brand name Arexvy and may be ready for distribution by this fall. A new antibody treatment called nirsevimab could also provide an effective option for protecting infants from RSV complications, with an FDA approval decision expected later this year.