Abstract
BACKGROUND: Comparative data on the disease burden of respiratory syncytial virus (RSV) versus other respiratory viruses in adults with chronic lung disease (CLD; asthma, COPD, or bronchiectasis) remain limited. This study aimed to compare clinical outcomes associated with RSV, influenza, and SARS-CoV-2 in this population during a period that largely preceded widespread adult RSV vaccine uptake. METHODS: Adult patients diagnosed with CLD and confirmed to have RSV, influenza, or Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection through combo tests including polymerase chain reaction or rapid antigen testing from June 2022 to April 2024 were included. A total of 82,871 participants diagnosed with CLD who tested positive for RSV, influenza, or SARS-CoV-2 using combo tests were included in the analysis. Patients with co-existing viral infections were excluded. Short-term adverse outcomes were defined as events occurring within 28 days after the index date, while long-term adverse outcomes were defined as events that occurred between 12 to 52 weeks. RESULTS: After propensity score matching, RSV-infected patients had higher rates of exacerbations compared to those with influenza (HR:1.37, 95% CI:1.28–1.47) and those with SARS-CoV-2 (HR:2.98, 95% CI:2.73–3.26). These patients also showed an increased requirement for mechanical ventilation compared to those with influenza (HR:1.50, 95% CI:1.29–1.75) and those with SARS-CoV-2 (HR:1.97, 95% CI:1.67–2.33). Additionally, RSV-infected individuals experienced higher incidences of acute decompensated heart failure compared to influenza (HR:1.32, 95% CI:1.20–1.46), and (HR:1.46, 95% CI:1.32–1.61) relative to SARS-CoV-2, respectively. CONCLUSIONS: RSV infection in patients with CLD revealed higher disease severity compared to influenza and SARS-CoV-2, warranting increased clinical attention for this population. SUMMARY: In this national cohort spanning June 2022 to March 2024, adults with chronic lung disease contracting RSV, influenza or SARS-CoV-2 were analyzed. Relative to the other viruses, RSV infection led to higher emergency visits, hospitalizations and mechanical ventilation, highlighting an urgent prevention gap. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12931-026-03526-4.