Daijiworld Media Network – New Delhi
New Delhi, Nov 29: An international team of scientists has uncovered strong evidence that respiratory syncytial virus (RSV) infection in early infancy sharply increases the risk of developing childhood asthma, especially among children with a family history of allergies or asthma.
Published in Science Immunology, the study highlights that protecting newborns from RSV could significantly reduce future asthma cases.
Prof. Bart Lambrecht of VIB (Flanders Institute for Biotechnology) and Ghent University said childhood asthma is driven by many factors, but the study shows a clear interaction between early RSV infection and genetic allergy risk.
"We found that early-life RSV infection and genetic allergy risk interact in a very specific way that pushes the immune system toward asthma. The encouraging news is that this process can be prevented," he said.
The collaborative research team, which included scientists from Denmark, combined data from national health registries covering all Danish children and their parents with controlled laboratory studies. They discovered that infants infected with RSV in the first months of life are more likely to develop an immune system that overreacts to common allergens such as house dust mites.
This vulnerability becomes particularly strong when asthma or allergies run in the family. Antibodies related to allergies, passed from parents to newborns, further heighten the infant's sensitivity.
Importantly, the researchers found that when newborns were protected from RSV in experimental models, the harmful immune changes did not take place — effectively preventing the development of asthma.
Prof. Hamida Hammad of VIB-UGent emphasised the real-world implications of the findings.
"With RSV prevention now becoming widely accessible, we have an opportunity to improve long-term respiratory health, not just prevent RSV hospitalisations," she said. "This is not just a laboratory insight. It's a message that should help parents choose RSV prevention with confidence."
Maternal vaccination during the third trimester and passive immunisation of newborns with long-acting antibodies are now being rolled out across several countries. However, despite their proven ability to prevent severe RSV infections, uptake remains inconsistent.
Prof. Lambrecht added that this moment calls for alignment between science, policy, and paediatric care.
"If preventing RSV infection also reduces asthma risk, the benefits for families and health systems could be enormous," he said.