A major study presented today at ESCMID Global 2025 has revealed that adults with respiratory syncytial virus-associated acute respiratory infection (RSV-ARI) face a 2.7-fold higher risk of death within one year compared to the general population.1
The findings underscore the significant, yet often under-recognised, long-term health and economic burden of RSV-ARI in adults, particularly among those with underlying conditions such as chronic obstructive pulmonary disease (COPD) and asthma.
RSV-ARI refers to a group of illnesses caused by respiratory syncytial virus (RSV), a common and highly contagious virus that primarily affects the respiratory tract.2 While its impact on infants and young children is well-documented, it can also lead to serious complications in adults, including pneumonia and chronic respiratory disease.3 Despite these risks, the full extent of its burden in adults remains poorly understood.
The Danish nationwide cohort study analysed data from 5,289 adults (≥18 years) diagnosed with RSV-ARI between 2011 and 2022, comparing them to 15,867 matched controls from the general population. Clinical and economic outcomes were assessed up to 365 days following RSV-ARI onset.
In addition to the increased risk of death, the study found that adults with RSV-ARI experienced significantly worse health outcomes. Over the course of the 365-day follow-up period, exacerbations of COPD and asthma were 3.1 and 4.6 times more frequent in RSV-ARI patients, respectively. Hospitalisation rates for RSV-ARI patients were more than double those of the control group (57% versus 28%), and intensive care unit admissions were nearly four times higher (5.3% versus 1.4%).
The economic impact of RSV-ARI was also considerable. Total direct healthcare costs for RSV-ARI patients during the 365-day follow-up amounted to €20,181, more than double the €8,085 spent on healthcare for individuals within the control group.
“One of the most striking findings from this study was the prolonged and significant impact of RSV-ARI”, said lead study author, Maria João Fonseca. “Even after the acute phase, patients continued to experience worse outcomes compared to the general population. This underscores just how serious and enduring the effects of RSV-ARI can be.”
“Exacerbations of COPD and asthma were the most common adverse clinical outcomes. These pre-existing conditions are already challenging in themselves, and RSV-ARI exacerbates their severity. Because of this, it’s crucial that we pay closer attention to patients with these underlying conditions to prevent further, potentially life-threatening complications.”
Commenting on the measures needed to reduce the impact of RSV-ARI, co-author, Stanislava Bratković commented, “Vaccination has proven highly effective in preventing severe outcomes from RSV. Given the significant burden of RSV-ARI highlighted by our study, prioritising vaccination for vulnerable populations is essential to reduce both health complications and associated costs.”
She concluded, “Looking forward, we hope our findings will inspire further research into the broader clinical and societal burden of RSV, particularly in high-risk groups. This will help shape more targeted preventive strategies and ensure timely interventions for those who need it most.”
ENDS
Notes to editors:
A reference to ESCMID Global must be included in all coverage and/or articles associated with this study.
For more information or to arrange an expert interview, please contact the ESCMID Press Office at: communication@escmid.org
About the study author
Maria João Fonseca graduated in 2009 and completed her PhD in Public Health in 2015. From 2009-2019, she worked as a researcher at the University of Porto, and lectured Epidemiology classes. During 2020, Fonseca worked as epidemiologist in the Portuguese Institute of Oncology. She joined IQVIA in 2021 as an epidemiologist, supporting scientific projects on a wide range of indications. In 2023, Fonseca became part of GSK’s VEO Europe team, leading studies across Europe to support the launch of Arexvy, and in 2024 moved into a global role, still supporting Arexvy. Fonseca is the first author of several peer-reviewed publications, as well as communications presented in international conferences.
Stanislava Bratković holds a Medical Doctor degree, obtained in 2005. Currently, she works as a Medical Advisor for Vaccines at GSK in Denmark, a position she has held since May 2019. Prior to this, she held various Medical Affairs and clinical trial management roles in pharmaceutical companies.
This study has been sponsored and funded by GSK.
About the European Society of Clinical Microbiology and Infectious Diseases:
The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) is the leading society for clinical microbiology and infectious diseases in Europe. ESCMID is proud to unite over 12,000 members as well as 45,000 affiliated members through 77 national and international affiliated societies. ESCMID’s mission is to champion medical progress in infection for a healthier tomorrow and plays an important role in emerging infectious diseases and antimicrobial resistance education and research.
Website: www.escmid.org/
References:
Fonseca, M. J., Bratković, S., et al. (2025). Clinical and economic burden of respiratory syncytial virus in adults with acute respiratory infections – a Danish nationwide cohort study. Oral presentation. ESCMID Global 2025.
Mayo Clinic. (2023). Respiratory syncytial virus (RSV): Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/respiratory-syncytial-virus/symptoms-causes/syc-2035309
DeMartino, J. K., Lafeuille, M.-H., et al. (2023). Respiratory syncytial virus–related complications and healthcare costs among a Medicare-insured population in the United States. Open Forum Infectious Diseases, 10(5), ofad203. https://doi.org/10.1093/ofid/ofad203 END
