Respiratory syncytial virus infection.

Respiratory syncytial virus (RSV), long recognised as the major viral pathogen of the lower respiratory tract of infants, has also been implicated in severe lung disease in adults, especially the elderly. This fact, and the demonstration that passive prophylaxis with either polyclonal or monoclonal antibody to RSV prevents severe lung disease in high-risk infants and children, has led to renewed interest in the immune mechanisms surrounding protection, and the development of vaccines