Clinical features and outcomes of viral respiratory infections in adults during the 2023–2024 winter season
Eleni Rousogianni, Garyfallia Perlepe, Stylianos Boutlas, Georgia Rapti, Evdoxia Gouta, Eleni Mpaltopoulou, Giorgos Mpaltopoulos, Dimitrios Papagiannis, Aristomenis K. Exadaktylos, Konstantinos I. Gourgoulianis, Erasmia Rouka
Abstract
The role and impact of viral infections remain a subject of interest, yet comparative data on influenza A/B, RSV, and SARS-CoV-2 in both hospitalized and non-hospitalized patients are limited. In this observational study, we analyzed data from adult patients with respiratory infections who underwent rapid testing for Influenza A/B, RSV, SARS-CoV-2, and Adenovirus between October 2023 and March 2024. Symptoms at emergency department presentation, laboratory results, risk factors, clinical course, and outcomes were assessed. Among 1,402 patients with respiratory infections, Influenza A was the most prevalent virus and the leading cause of hospitalizations, with the longest stay (mean: 9.86 days). SARS-CoV-2 was the second most common, primarily affecting older patients (mean age: 79 years), associated with the highest in-hospital mortality. RSV ranked third in prevalence, had the highest hospitalization rate among those infected, and was characterized by bronchospasm, with 25% of hospitalized patients requiring high-flow nasal cannula (HFNC). Influenza B primarily affected younger individuals and had a negligible hospitalization rate. SARS-CoV-2 patients sought care the fastest, while RSV patients had the most prolonged symptom duration before seeking medical attention. Despite differences in care-seeking timing, most Flu-A, Flu-B, and SARS-CoV-2 patients recovered within 2-5 days, with no significant difference observed. Vaccine effectiveness against Influenza A was 49.5%. This estimate should be interpreted with caution due to potential confounding by age and comorbidities. These findings offer comparative insights into the clinical burden of respiratory viruses during the 2023-2024 season, reflecting patterns in the post-pandemic era.