RSV-Positive Children <5 Years Presenting to Pediatric Emergency Departments in Türkiye: TRUST-RSV

This is a multicenter, prospective observational cohort study conducted in pediatric emergency departments in Türkiye over a consecutive RSV season. Eligible participants are children younger than 5 years who present to a participating pediatric ED with at least one compatible clinical diagnosis and have RSV infection confirmed by a nasopharyngeal sample using either a rapid antigen test or PCR, based on local site capacity. Written informed consent will be obtained from a parent or legal guardian prior to study procedures. Standardized case report forms will be used to collect demographics (age, sex, region, socioeconomic indicators), relevant risk factors (e.g., prematurity, congenital heart disease, chronic lung disease, passive smoke exposure, breastfeeding status), presenting symptoms, vital signs and physical examination findings, diagnostic evaluations (radiology and laboratory results as available), and clinical management and outcomes. Outcomes of interest include ED observation duration, disposition (discharge vs hospitalization), ICU admission, and, when applicable, the need for oxygen or ventilatory support. Data will be entered into a secure centralized database. The study will evaluate seasonal and regional patterns and will explore predictors of severe outcomes among RSV-positive children using multivariable models.