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Respiratory syncytial (sin-SISH-uhl) virus, or RSV, is a common respiratory virus that usually causes mild, cold-like symptoms. Most people recover in a week or two, but RSV can be serious, especially for infants and older adults. In fact, RSV is the most common cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia (infection of the lungs) in children younger than 1 year of age in the United States. It is also a significant cause of respiratory illness in older adults.

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Fast Facts

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CDC Featured Podcast


Dr. Eileen Schneider talks about RSV, a common cause of respiratory illness in young children.

Listen To This Podcast (4:22)