What is Respiratory Syncytial Virus (RSV)?
RSV is the most common cause of serious respiratory infections (mostly bronchiolitis [inflammation of the small airways in the lung] and pneumonia) in infants and young children. Many of these children are hospitalized. Infants less than 6 weeks old, and children with underlying conditions such as premature birth, heart disease or lung disease, are much more likely to be hospitalized with RSV. RSV is also causes cold-like symptoms and pneumonia in older children and adults. RSV infection is quite common; virtually all children in the United States have been infected with RSV by the age of 3 years [LaVia et al, 1992]. Up to 126,300 children are hospitalized annually in the United States for bronchiolitis or pneumonia [Shay et al, 1999]. Annual RSV epidemics peak in February and are responsible for one-fourth to one-third of all pediatric hospitalizations for pneumonia [La Via et al, 1992] and one-half of the hospitalizations for bronchiolitis [Heilman, 1990]. Native American children ha
