Epidemiology, burden and clinical course in RSV-infected older adults in the outpatient setting in Germany

<bold>Background:</bold> Acute respiratory infections (ARI) caused by respiratory syncytial virus (RSV) impose a significant burden on health systems, particularly affecting older adults. The epidemiology and impact of RSV infections are not well defined within the outpatient setting. This study aimed to describe the clinical course of RSV and its complications and to estimate the medically attended incidence of RSV in the outpatient setting in Germany in the first season from the BUCOSS study. <bold>Methods:</bold> BUCOSS is a multi-seasonal ongoing observational, active surveillance study including patients with ARI from 16 general and pulmonologists practices. The clinical course and complications following an RSV infection were recorded over a period of 28 days. <bold>Results:</bold> Among 406 patients with ARI, RSV was detected via PCR in 53 patients (13%). Compared to the entire ARI cohort, RSV patients more often experienced rales/wheezing, purulent sputum and runny/congested nose. Symptom duration averaged 19 days with 23% of RSV patients still having symptoms at day 28. Almost half of the RSV patients (49%) had a chronic lung disease, mainly asthma and COPD (n=24) with 12 patients experiencing exacerbations. The medically attended RSV-ARI incidence among 60+ was 955/100,000 persons with the highest rate in those aged 70-79 (2,223/100,000). Health-related quality of life increased during the observation period with slightly lower values in patients with LRTI than with URTI but comparable values on day 28. LRTI resulted in considerably higher costs than URTI. <bold>Conclusion:</bold> BUCOSS provides a comprehensive understanding of RSV offering valuable insights for future research and informing public health strategies.