Respiratory Syncytial Virus and COVID‐19 in Hospitalized Adults in Spain: Clinical, Radiological Features and Antimicrobial Use

Background Lower respiratory tract infections (LRTIs) impose a significant global burden, with over 400 million cases annually. This study compares the clinical features of adults hospitalized with respiratory syncytial virus (RSV) and COVID‐19, two viral pathogens with similar presentations but differing epidemiology. Methods This cross‐sectional study analyzed 100 adult cases with PCR‐confirmed RSV or COVID‐19, admitted to the hospital from January 2022 to March 2023. Data on clinical, sociodemographic, radiological, treatment, and laboratory variables were extracted from records. Results Both cohorts consisted of elderly patients (> 70 years) with multiple comorbidities. Notably, the RSV group had a higher prevalence of CHF (24% vs. 10%, p = 0.014) and COPD (29% vs. 9%, p = 0.001). Radiologically, 51% of RSV patients had normal findings, whereas 48% of COVID‐19 patients exhibited bilateral pneumonia ( p = 0.001). Antimicrobial treatment was administered to 75% of RSV patients compared to 41% of COVID‐19 patients ( p < 0.001). RSV patients had marginally higher leukocyte and neutrophil counts, while COVID‐19 patients showed significantly elevated CRP, ferritin, LDH, ALT, and potassium levels. Conclusions Distinct profiles were identified between hospitalized RSV and COVID‐19 patients. RSV patients, mostly older with CHF and COPD, were more likely to receive antibiotics, possibly reflecting the lack of targeted therapies. In contrast, COVID‐19 patients exhibited higher inflammation and lung involvement. These findings highlight the need to refine treatment protocols, enhance antimicrobial stewardship, and develop specific RSV therapies alongside preventive strategies for high‐risk groups.