Respiratory Syncytial Virus
Respiratory syncytial virus, or RSV, is a common respiratory virus that usually causes mild, cold-like symptoms. Most people recover from RSV in a week or two, but RSV can be serious, especially for infants and older adults.
RSV causes coughs and colds every winter and is the most common cause of bronchiolitis (inflammation of the small airways in the lungs) in infants. RSV is a significant cause of severe respiratory illness among children under 2 years of age and is also the most common cause of hospital admissions due to acute respiratory illness in young children. By two years of age, nearly all children have been infected with RSV at least once.
RSV is a seasonal virus with outbreaks typically occurring in the winter months with the highest numbers of infections usually reported in December and January every year, though the size of the peak varies from winter to winter.