Respiratory syncytial virus, or RSV, is a respiratory illness caused by a virus.
Anyone can be infected, but RSV most often causes serious illness in infants and very young children. The virus can also cause serious illness in elderly people and those with a weakened immune system.
RSV infections typically occur during the Fall and Winter.
RSV is spread through contact with droplets from the nose and throat of infected people when they cough and sneeze. RSV can also spread through dry respiratory secretions on bedclothes and similar items.
Typical symptoms resemble the common cold. However, RSV infection can also result in pneumonia, especially in the very young, the very old or those who have weakened immune systems. However, mild or inapparent illness may occur. Symptoms may persist for a few days to a number of weeks.
Symptoms generally begin 4 to 6 days after exposure. Symptoms generally develop slowly over a period of several days. The contagious period is usually 10 days after symptoms begin, but occasionally is longer.
RSV is usually diagnosed based on the appearance of typical symptoms. The use of specific laboratory tests is often limited to cases of severe illness and to special outbreak investigations.
A medication called ribavirin is effective against RSV infection if begun in the first few days after symptoms appear. Because RSV infection often resolves on its own, treatment of mild symptoms is not necessary for most people. Antibiotics are not effective treatments for viral illnesses such as RSV infection (although in certain patients, antibiotics may be used to treat bacterial infections which have complicated the RSV infection in that patient).
Immunity after RSV infection does occur, but is not life-long. Repeat infections are known to occur, although they may be milder. The duration is unknown.
At this time, there are no licensed vaccines for the prevention of RSV infection. When RSV infections are noted in a facility such as a hospital or nursing home, contact isolation (to minimize person-to-person spread) and handwashing by health care workers have been shown to limit spread of the virus. As with any respiratory illness, all people should cover their face when coughing and sneezing.
Last Updated: October 2000