Respiratory syncytial virus in healthy adults: the cost of a cold.

Respiratory syncytial virus (RSV) is well recognized as a major pathogen of lower respiratory tract infection and hospitalization in young infants. More recently the pathogenicity of RSV has been demonstrated in elderly adults, institutionalized individuals, and those with compromised immune function. In these populations RSV spreads with ease and frequently results in severe or fatal cardiopulmonary complications. In younger, healthy adults, however, the manifestations and importance of RSV infection have been studied little, and RSV is generally not considered as a cause of respiratory illness in this healthy, working population. RSV occurs in yearly outbreaks and is highly contagious. Immunity after infection is neither complete nor durable. Repeated infections, therefore, occur throughout life. In most cases these recurrent infections involve the upper respiratory tract and thus do not receive a specific diagnosis. However, recent studies indicate that in the younger, healthy adult these respiratory illnesses tend to be more severe than the average 'cold' and may have manifestations similar to influenza. An appreciable proportion results in work absence. Thus, the emerging information suggests that RSV infection clearly occurs frequently in healthy adults in contact with children, but is generally not diagnosed. The potential burden on the healthcare system is unestimated, possibly unappreciated, and should be considered in strategies being developed for preventing RSV infection.