Respiratory Viruses

The respiratory viruses as a group are the most common cause of an acute infectious illness in developed societies. The immunocompromised state of many cancer patients constitutes the basis for the frequent failure of the host to promote a normal and rapid recovery from an acute respiratory viral infection and results in a more severe and prolonged infection that causes significant morbidity and mortality in these patients. Those respiratory viruses that are most prevalent and most prone to produce lower respiratory illnesses and pneumonia in healthy hosts, RSV, influenza viruses, and parainfluenza viruses, are those most likely to cause severe illness and pneumonia leading to hospitalization in immunocompromised persons. However, viruses less prone to produce a lower respiratory illness but that are highly prevalent, such as rhinoviruses, may frequently be associated with severe illness. The limited availability of antivirals and vaccines for the acute respiratory viruses means that these infections will continue to be important for many years and dictate a need for utilizing infection control procedures as much as possible, particularly in hospitals and institutions, so as to minimize spread. Efforts to develop specific vaccines are important as their use could prevent as well as reduce exposure of cancer patients to these viruses. Development of specific antivirals is important for use in immunocompromised patients as normal recovery mechanisms may be seriously impaired.