1755. Hospitalizations for Respiratory Viruses among Children 5–17 Years of Age in the Pre-COVID-19 Pandemic Era, the New Vaccine Surveillance Network, 2016–2020

Abstract Background Respiratory viruses are a substantial cause of hospitalization in infants and young children; less is known about their contribution to ARI-associated hospitalizations in children ≥ 5 years of age. Methods We conducted prospective, active surveillance among children ages 5–17 years hospitalized for acute respiratory illness (ARI) at 7 pediatric medical institutions comprising the New Vaccine Surveillance Network (NVSN) during December 1, 2016 through April 1, 2020. Children hospitalized for fever and/or respiratory symptoms were consented for enrollment. Demographic and clinical data were collected through parent/guardian interviews and chart abstraction. Mid-turbinate nasal and/or throat specimens were collected and tested using molecular methods for respiratory syncytial virus (RSV), influenza, parainfluenza viruses 1–4 (PIV), human metapneumovirus (HMPV), rhinovirus/enterovirus (RV/EV), adenovirus (AdV), and seasonal coronaviruses (CoV). Results Of 6,992 eligible children, 4,011 (57%) were enrolled and 3,953 (99%) had respiratory specimens obtained. Median age of enrolled children was 8.9 years (IQR: 6.6, 12.2), 55% were male, 38% were non-Hispanic White, and 76% had ≥ 1 underlying medical condition (Table). Respiratory viruses were detected in 54% of patients hospitalized with ARI: RV/EV occurred most frequently (32%), followed by influenza (11%) and RSV (5%) (Figure). Respiratory virus coinfections were detected in 133 (3%) patients. Common symptoms reported included cough, congestion/runny nose, and fever, and a majority of children experienced dyspnea and wheezing. Median length of hospitalization was 2 days (IQR: 1,3); 687 (17%) patients were admitted to an intensive care unit, of whom 119 (17%) required intubation. Figure. Detection and seasonality of respiratory viruses in hospitalized children 5–17 years, 2016–2020 Conclusion Respiratory viruses were detected in more than half of ARI-related hospitalizations in children aged ≥ 5 years. This multi-center, multi-year, pre-pandemic assessment provides baseline data to evaluate for possible changing epidemiology of respiratory viruses after the onset of the COVID-19 pandemic. Disclosures Mary A. Staat, MD, MPH, CDC: Grant/Research Support|Cepheid: Grant/Research Support|Merck: Grant/Research Support|NIH: Grant/Research Support|Pfizer: Grant/Research Support|Up-To-Date: Honoraria Rangaraj Selvarangan, BVSc, PhD, D(ABMM), FIDSA, FAAM, Abbott: Honoraria|Altona Diagnostics: Grant/Res