Seasonal community-acquired respiratory virus infections in patients with cancer—Epidemiological and clinical overview, an analysis of the multicenter OncoReVir registry

INTRODUCTION: Community-acquired respiratory viruses (CARV) can cause severe infections in patients with cancer. To characterize epidemiology and outcome, the multicenter registry OncoReVir was established in November 2018. PATIENTS AND METHODS: From November 2018 to October 2024, 2080 patients with cancer and CARV infection were enrolled. Only patients with a single CARV infection were analyzed (n = 1975). Data included demographics, cancer characteristics, and clinical course. A subgroup (n = 381) compared epidemiology and outcome across pre-, peri-, and postpandemic periods. Predefined endpoints were pneumonia, ICU admission, and infection-related mortality. RESULTS: Median age was 61 years (interquartile range 52-69), 42.5% were female, and 85.5% had hematological diseases. Most frequent CARVs were severe acute respiratory coronavirus 2 (SARS-CoV-2) (36%), influenza (22.5%), human parainfluenza virus (hPIV, 12.5%), and respiratory syncytial virus (RSV, 12%). Epidemiology (excluding SARS-CoV-2) shifted by period: prepandemic, influenza predominated (70.5%); pandemic, RSV (31%); postpandemic, RSV (27.5%), and hPIV (25.5%). Overall, 53% patients were hospitalized, 7% required ICU care, pneumonia occurred in 22.5%, and infection-related mortality was 4% (overall mortality 28%). Endpoint occurrence varied minimally across phases. Influenza drove prepandemic severity, whereas other CARVs became relevant during/after the pandemic. CONCLUSION: CARV epidemiology in patients with cancer changed substantially across pandemic phases, while clinical severity and infection-related mortality remained largely unchanged.