No association between disease severity and respiratory syncytial virus subtypes RSV-A and RSV-B in hospitalized young children in Norway

PLoS One. 2024 Mar 11;19(3):e0298104. doi: 10.1371/journal.pone.0298104. eCollection 2024.


Objective: There is conflicting evidence whether subtypes of Respiratory syncytial virus have different seasonality or are differentially associated with clinical severity. We aimed to explore the associations between disease severity and RSV subtypes RSV-A and RSV-B and to describe the circulation of RSV subtypes pattern by season and age.

Methods: Active prospective hospital surveillance for RSV-A and RSV-B in children <59 months of age was conducted during 2015-2018. All febrile children 12-59 months of age were enrolled, whereas children <12 months were eligible if presenting with fever or respiratory symptoms. Risk factors and upper and lower respiratory tract infection was identified by linkage to national registry data and analyzed using penalized maximum likelihood logistic regression.

Results: Both RSV-A and B were found to co-circulate throughout all three study seasons, and no clear seasonal pattern was identified. Likewise, we found no association between sex or measures of severity with RSV-A or RSV-B. There was significantly more RSV-A than RSV-B among children with comorbidities.

Conclusions: No association was found between disease severity or sex and RSV subtypes RSV-A and RSV-B in hospitalized young children in Norway.

MeSH terms

  • Child
  • Child, Preschool
  • Fever
  • Hospitalization
  • Humans
  • Infant
  • Norway / epidemiology
  • Patient Acuity
  • Prospective Studies
  • Respiratory Syncytial Virus Infections*
  • Respiratory Syncytial Virus, Human*
  • Respiratory Tract Infections* / epidemiology
  • Seasons

Grants and funding

This work was supported by The Research Council of Norway ( [240207/F20]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.