Respiratory Syncytial Virus Infection (RSV)

Last Reviewed: October 2011

What is respiratory syncytial virus infection?

Respiratory syncytial virus, or RSV, infection is a respiratory illness caused by a virus.

Who gets RSV infection?

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.

When do RSV infections occur?

RSV infections typically occur during the fall and winter.

How is RSV spread?

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 dried respiratory secretions on bedclothes and similar items. RSV can remain on hard surfaces for several hours and on skin for shorter amounts of time.

What are the symptoms of RSV infection?

Typical symptoms resemble the common cold. However, RSV infection can also result in pneumonia, especially in the very young, the very old or those with weakened immune systems. However, mild or unnoticeable illness may occur. Symptoms may persist for a few days to a number of weeks.

How soon after exposure do symptoms appear?

Symptoms generally begin four to six days after exposure. Symptoms generally develop slowly over a period of several days. The contagious period is usually less than 10 days after symptoms begin, but occasionally is longer.

How is RSV infection diagnosed?

RSV is usually diagnosed from the appearance of typical symptoms. The use of specific laboratory tests is often limited to cases of severe illness and to special outbreak investigations.

What is the treatment for RSV infection?

A medication called ribavirin is effective against RSV infection if begun in the first few days after symptoms appear. Because RSV infection is often resolved 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).

Does past infection with RSV make a person immune?

Immunity after RSV infection does occur, but is not lifelong. Repeat infections are known to occur, although they may be milder. The duration is unknown.

What can be done to prevent the spread of RSV?

At this time, two products that contain RSV antibodies are available to prevent RSV infection. These products are given once a month during the RSV season and are recommended for certain high-risk children. When RSV infections are noted in a facility such as a hospital or nursing home, contact isolation (to minimize person-to-person spread) and hand washing 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.