Burden of Respiratory Syncytial Virus Among Older Adults With an Acute Respiratory Infection: A Prospective Study in Six European Countries

Clin Infect Dis. 2026 Jul 8;82(6):e1266-e1276. doi: 10.1093/cid/ciag146.

Abstract

Background: Respiratory syncytial virus (RSV) primarily affects the respiratory tract, with a high burden among older adults. We aimed to estimate the prevalence and characteristics of RSV-associated respiratory infections in community-dwelling older adults across Europe.

Methods: A prospective, observational study was conducted in six European countries over three consecutive RSV seasons (October 2021 until April 2024). Non-RSV vaccinated participants (age ≥60 years) presenting with symptoms of acute respiratory infection (ARI) at general practitioners and outpatient clinics/outpatient hospitals were recruited. Respiratory syncytial virus and other respiratory viruses were detected using a combined nasal and throat swab. Diary cards and regular phone contacts were used to collect information on onset and resolution of symptoms. The prevalence of RT-PCR confirmed RSV-ARI (cRSV-ARI) was estimated, as well as symptom duration, underlying comorbidities, prevalence of RT-PCR confirmed RSV lower respiratory tract disease (cRSV-LRTD), complications, hospitalizations, and co-infections.

Results: A total of 2573 participants were enrolled (139 with cRSV-ARI). The prevalence of cRSV-ARI varied by season: 3.6% in Season 1, 9.3% in Season 2, and 4.2% in Season 3. The most frequently reported upper respiratory, lower respiratory, and systemic symptoms were nasal congestion/rhinorrhea, cough, and fatigue (cRSV-ARI: 83.1%, 97.8%, and 64.0%; non-cRSV-ARI: 78.0%, 95.0%, and 68.2%). The overall prevalence of cRSV-LRTD was 3.9% in Season 1, 12.5% in Season 2, and 7.3% in Season 3.

Conclusions: This study highlights the substantial burden of RSV among older adults in Europe and reflects the shift in RSV epidemiology due to the COVID-19 pandemic, indicating a return to prepandemic seasonality trends.

Clinical trial registration: Not applicable.

Keywords: acute respiratory infection; community-dwelling older adults; prevalence; respiratory syncytial virus.

Publication types

  • Observational Study

MeSH terms

  • Acute Disease
  • Aged
  • Aged, 80 and over
  • Coinfection / epidemiology
  • Coinfection / virology
  • Europe / epidemiology
  • Female
  • Hospitalization / statistics & numerical data
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Prospective Studies
  • Respiratory Syncytial Virus Infections* / epidemiology
  • Respiratory Syncytial Virus Infections* / virology
  • Respiratory Syncytial Virus, Human* / isolation & purification
  • Respiratory Tract Infections* / epidemiology
  • Respiratory Tract Infections* / virology
  • Seasons

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