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Respiratory syncytial (sin-SISH-uhl) virus, or RSV, is a respiratory virus that infects the lungs and breathing passages. Most otherwise healthy people recover from RSV infection in 1 to 2 weeks. However, infection can be severe in some people, such as certain infants, young children, and older adults. In fact, RSV is the most common cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia in children under 1 year of age in the United States. In addition, RSV is more often being recognized as an important cause of respiratory illness in older adults.

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CDC Featured Podcast


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

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