Retrospective Observational Multicenter Study on the Burden of Hospitalized Patients With Respiratory Tract Infection

This multicenter retrospective real-world data study will evaluate the burden of respiratory tract infection (RTI)-related hospitalizations in up to 10 Dutch hospitals between 2018 and 2026. The study aims to quantify: * Hospitalization rates * Healthcare resource utilization (LOS, ICU admissions, readmissions) * Clinical outcomes (including mortality) * Direct healthcare costs * Pathogen-specific burden (e.g., RSV, influenza, SARS-CoV-2) Using linked hospital, laboratory, and administrative data, outcomes will be analyzed by age group, comorbidities, pathogen, and respiratory season. The expected cohort size is approximately 60,000-70,000 patients. The results will provide evidence to support Dutch public health policy, including RSV immunization strategies, healthcare capacity planning, and antimicrobial stewardship.