Protecting Newborns from RSV Reduces Asthma Risk — Evidence Review
Published in Science Immunology, by researchers from VIB, Ghent University, University of Ghent, Research Foundation -- Flanders
Researched by
— the AI search engine for science
Table of Contents
Belgian researchers report that early-life RSV infection sharply increases the risk of childhood asthma, particularly in infants with inherited allergy risk; related studies mostly support a link between early RSV infection and later asthma, though some findings are mixed. The new study, published in Science Immunology, suggests that protecting newborns from RSV could prevent asthma development.
- Several large population-based and cohort studies have found that RSV infection in infancy is associated with an increased risk of asthma, supporting the premise of the new findings and highlighting the potential benefit of RSV prevention strategies 2 3 4.
- However, intervention studies and meta-analyses show mixed results regarding whether RSV prophylaxis in preterm or high-risk infants consistently reduces long-term asthma rates, with some benefits observed in specific subgroups or for recurrent wheezing but less clear effects on physician-diagnosed asthma 1 5 6.
- The interplay between genetic predisposition (family history of allergy/asthma), timing of RSV infection, and immune response is increasingly recognized as a key factor in asthma development, with recent studies underscoring the importance of early-life prevention, especially in at-risk populations 7 9.
Study Overview and Key Findings
Childhood asthma remains a significant public health issue in Europe, impacting up to 15% of children and imposing considerable burdens on families and healthcare systems. Identifying modifiable early-life risk factors is a high priority for prevention efforts. This new study from Belgian and Danish researchers addresses a crucial gap: the interaction between severe RSV infection in infancy and genetic allergy risk, and how these factors contribute to asthma development. By combining national health registry data with laboratory models, the research offers new insights into how RSV exposure and inherited risk factors may jointly shape immune responses and long-term respiratory health. The findings are timely as RSV preventive tools (maternal vaccination, monoclonal antibodies) are becoming more widely available, prompting questions about their broader impact beyond immediate infection prevention.
| Property | Value |
|---|---|
| Study Year | 2023 |
| Organization | VIB, Ghent University, University of Ghent, Research Foundation -- Flanders |
| Journal Name | Science Immunology |
| Authors | Prof. Bart Lambrecht, Prof. Hamida Hammad |
| Population | Newborns, infants with RSV infection |
| Methods | Animal Study |
| Outcome | Asthma risk, immune responses to allergens |
| Results | Protecting newborns from RSV prevents asthma development. |
Literature Review: Related Studies
To situate the new findings within the broader research landscape, we searched the Consensus database, which indexes over 200 million research papers. The following search queries were used to identify relevant studies:
- RSV prevention asthma development newborns
- asthma risk reduction RSV exposure
- newborn respiratory infections asthma outcomes
Below is a summary of key topics and findings from the literature:
| Topic | Key Findings |
|---|---|
| Does RSV infection in infancy increase the risk of childhood asthma? | - Multiple large cohort and systematic review studies confirm a strong association between early-life RSV infection and higher risk of wheezing and asthma in children 2 3 4 7 9 10. - The risk is particularly pronounced following severe RSV infection, and may persist for several years 7. |
| Does preventing RSV infection reduce later asthma or wheeze? | - Randomized controlled trials and meta-analyses show mixed results: some report reduced recurrent wheeze with RSV immunoprophylaxis, especially in specific subgroups (e.g., preterm infants), but effects on physician-diagnosed asthma are less clear 1 5 6. - Subgroup analyses suggest that certain populations (e.g., those with high adherence to prophylaxis or specific gestational ages) may benefit more 5 6. |
| What mechanisms link RSV infection to asthma development? | - Studies highlight that early RSV infection may disrupt immune and lung development, especially in infants with genetic predisposition to allergies/asthma 3 4 9. - The timing and severity of RSV infection, as well as the presence of maternal antibodies and neonatal immune characteristics, influence later asthma risk 7 9. |
| How do genetic and environmental factors interact in asthma risk after RSV? | - Evidence suggests RSV infection interacts with inherited allergy risk, amplifying immune responses to allergens and subsequently increasing asthma susceptibility 3 4 9. - Family history of asthma/allergy and early infection together appear to be particularly important risk modifiers 3 9. |
Does RSV infection in infancy increase the risk of childhood asthma?
Multiple observational and cohort studies, as well as systematic reviews, consistently report a strong association between RSV infection in the first year of life and subsequent increased risk of recurrent wheezing and asthma. The association is strongest for severe RSV infections and may persist for several years, especially if the infection occurs after the first six months of life 2 3 4 7 9 10. The new study reinforces this risk, noting that infants with both severe RSV infection and a family history of allergy/asthma are particularly vulnerable.
- Early-life RSV infection is a well-established risk factor for later asthma and wheezing disorders 2 3 4 9.
- Severe RSV infections confer a higher risk, and the effect may be more persistent if the first infection occurs after six months of age 7.
- The association between RSV and asthma is observed across different populations and healthcare systems 2 10.
- The current study's emphasis on genetic susceptibility aligns with the emerging view that both viral and host factors contribute to asthma risk 3 4 9.
Does preventing RSV infection reduce later asthma or wheeze?
While observational data support a link between RSV prevention and reduced wheezing, interventional studies show more nuanced results. Randomized controlled trials and meta-analyses generally find that RSV immunoprophylaxis reduces early-life wheezing, but the effect on physician-diagnosed asthma in later childhood is less consistent. Benefits may be more evident in specific subgroups, such as preterm infants or those with high adherence to prophylaxis 1 5 6. The new study adds mechanistic evidence from animal models that preventing RSV in early infancy can avert asthma development.
- RSV immunoprophylaxis reduces recurrent wheeze in infancy, though long-term effects on asthma are less certain 1 5 6.
- Some subgroup analyses indicate a reduction in asthma risk for infants with high prophylaxis adherence or certain gestational ages 5 6.
- The lack of consistent findings in all-cause asthma highlights the need for more targeted prevention and follow-up studies 1 6.
- The new study's experimental approach complements clinical findings by demonstrating a causal mechanism in animal models.
What mechanisms link RSV infection to asthma development?
The literature suggests that RSV infection may disrupt normal immune and lung development, especially in genetically susceptible infants. Interactions between early viral exposure, inherited allergy risk, and subsequent immune responses to environmental allergens are key drivers of asthma risk 3 4 9. Animal and human data indicate that RSV infection in infancy can skew immune responses toward allergy (Th2) profiles, which are associated with asthma.
- Early RSV exposure can alter lung and immune development, increasing susceptibility to asthma 3 4 9.
- Neonatal immune responses are biased toward Th2, which may enhance allergic sensitization after viral infections 9.
- The timing and severity of infection, as well as the presence of maternal antibodies, modulate this risk 7 9.
- The current study provides direct evidence that preventing RSV in infancy can block these immune changes and prevent asthma in experimental models.
How do genetic and environmental factors interact in asthma risk after RSV?
Several studies emphasize the interplay between genetic predisposition (family history of asthma/allergy) and environmental factors (RSV infection) in shaping asthma risk. The presence of allergen-specific maternal antibodies and inherited risk factors may amplify the immune response to early RSV exposure, increasing the likelihood of developing asthma 3 4 9. The new study's focus on gene-environment interaction is consistent with this body of evidence.
- Infants with a family history of allergy/asthma are at heightened risk of asthma after RSV infection 3 9.
- Maternal antibodies can increase sensitivity to allergens following RSV infection 9.
- Combined genetic and viral risk factors appear to have additive or synergistic effects 3 4.
- The new study supports these observations, identifying a specific interaction between inherited risk and early-life RSV infection in driving asthma development.
Future Research Questions
Although recent studies, including the present one, have advanced understanding of the connections between RSV infection, genetic predisposition, and asthma, important gaps remain. There is a need for further research to clarify causality, identify the most effective prevention strategies, and determine which children benefit most from RSV immunoprophylaxis or vaccination.
| Research Question | Relevance |
|---|---|
| Does RSV prevention in the general infant population reduce the incidence of asthma beyond high-risk groups? | Most studies focus on preterm or high-risk infants; it remains unclear if RSV prevention in the general population produces meaningful asthma risk reduction 1 2 6. |
| What are the long-term effects (beyond early childhood) of RSV infection or prevention on respiratory health? | Most follow-up studies end at age 5-6; research is needed on respiratory outcomes and asthma persistence into adolescence and adulthood 1 2 7. |
| How do genetic and environmental factors interact to modify asthma risk after RSV infection? | The interplay between family history, maternal antibodies, environmental exposures, and RSV infection requires further exploration to identify children most at risk and inform targeted prevention 3 4 9. |
| Which RSV prevention strategies (maternal vaccination, monoclonal antibodies, etc.) are most effective for asthma risk reduction? | Many prevention strategies are available or in development, but comparative effectiveness for asthma prevention is unknown 6 10. |
| What are the immunological mechanisms by which early RSV infection increases asthma risk, and can they be targeted? | Understanding immune pathways involved in RSV-induced asthma could lead to new preventive or therapeutic interventions beyond infection control 3 4 9. |
This article provides an evidence-based synthesis of current research on RSV infection, prevention, and childhood asthma, highlighting ongoing debates, knowledge gaps, and opportunities for future study.