Respiratory Syncytial Virus (RSV) is a common virus that causes respiratory illness in people of all ages. It is most common in winter and early spring but can occur year-round.
RSV is the leading cause of hospitalization among U.S. infants. Most children are infected during the first year of life and nearly all by age two. An estimated 79% of children younger than two hospitalized with RSV have no underlying medical conditions. RSV-associated hospitalizations are 4-10 times higher among American Indian and Alaska Native children.
RSV can also be dangerous for certain high-risk adults. Each year in the U.S., an estimated 60,000-120,000 older adults are hospitalized and 6,000-10,000 die from RSV infection.