Brief: Respiratory Syncytial Virus (RSV)

Respiratory Syncytial Virus (RSV) is an enveloped, single-stranded RNA virus that infects the respiratory tract. RSV is the most common cause of bronchiolitis and pneumonia in children younger than one-year-old, and almost all children will have had an RSV infection by their second birthday (CDC, 2022). RSV also affects adults, causing an estimated 6,000-10,000 deaths among adults 65 years and older, and millions of infections in the U.S. across all age groups each year (CDC, 2022). Among children under five years, RSV infection resulted in over 57,000 hospitalizations and two million outpatient visits each year in the U.S. from 2014-2017 (Rose et al., 2018). Critically, the 2022 RSV season showed much higher rates of RSV than observed in the past five years, and an earlier seasonal peak than expected from years prior.