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Respiratory syncytial (sin-SISH-uhl) virus, or RSV, is a respiratory virus that infects the lungs and breathing passages. Healthy people usually experience mild, cold-like symptoms and 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 in children younger than 1 year of age in the United States. In addition, RSV is being recognized more often as a significant cause of respiratory illness in older adults.

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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)