Epidemiologic characteristics and clinical outcomes of respiratory syncytial virus in hospitalized care in Lebanon: a prospective observational study

Introduction: The aim of this study was to describe the epidemiology and clinical outcomes of respiratory syncytial virus (RSV) infection in hospitalized children and adults from a sentinel surveillance network in Lebanon, and to compare the RSV rates and seasonality before and during COVID-19 pandemic. Methods: This study was based on the data from the Lebanese component of the Global Influenza Hospital Surveillance Network (GIHSN) during three consecutive seasons between 2019-2021 at six hospitals, following a standardized protocol based on age-specific criteria. Specimens were tested for RSV. The epidemiologic, clinical, and severity characteristics were analyzed. Descriptive statistics were used to summarize demographics, RSV rate, and outcomes. Univariate analyses were performed using Pearson's Chi-square or Fisher's exact test, and associations were expressed as unadjusted odds ratios (95% CI). A p-value ≤0.05 was considered significant. Results: From January 2019 to September 2021, 2,626 of 7,081 eligible inpatients were enrolled in the study, with 188 tested positives for RSV (7.3%). The majority (74.5%) of RSV-positive subjects were children under 5 years of age, and 9.6% of patients were ≥ 65 years of age. The positivity rate varied across seasons (2.1%-11.1%) (p-value