Respiratory syncytial virus infection: an emerging or unappreciated infection?

Respiratory syncytial virus (RSV) is a ubiquitous cause of respiratory infe ction with a worldwide distribution and seasonal occurrence. Natural immuni ty does not normally follow infection, and reinfection is the rule. Reinfec tion may even occur within a single season. Although its role in serious lo wer respiratory tract infection (LRTI) in infants is well recognized, the i mportance of RSV in disease of older children, adults and, especially in th e elderly, is poorly appreciated. In large surveillance studies, RSV is at least as important in contributing to respiratory morbidity and mortality a s influenza. These data would suggest that tens of millions of Americans su ffer respiratory disease (LRTI and upper respiratory tract infection [URTI] ) from RSV each winter. In addition, otitis media and episodic bronchospasm are complications following RSV infection. Unfortunately, there is no vacc ine yet available for prevention. Prevention of disease with a hyperimmune globulin (RSVIG) and with a monoclonal antibody (MAb) (palivizuMab) is poss ible, but only for those neonates and infants at highest risk of morbidity and mortality from RSV infection. Therapy with the only approved antiviral for this indication, ribavirin, is difficult, is of questionable efficacy, and the compound itself is teratogenic. Infection by RSV constitutes an eno rmous but unappreciated medical need worldwide.