Respiratory Syncytial Virus (RSV) Infection
What is respiratory syncytial virus (RSV)?
The respiratory syncytial virus (RSV) causes an illness that usually resembles a moderate to severe cold and is very contagious. RSV most often resolves on its own and does not cause major health concerns. This infection can become a problem when it is severe or leads to complications. Babies (especially those born prematurely), people with immune system problems, people with heart or lung problems, and older adults have an increased risk of developing complications from RSV infection.
Outbreaks of RSV infection generally occur at regular and predictable times each year, although they vary in severity. The number of infections usually peaks in the late fall, winter, and early spring in the United States and Europe. In tropical climates, epidemics occur during the rainy season.
What causes infection with RSV?
RSV infection is caused by a virus that attacks the respiratory tract—the nose, eyes, throat, and lungs. Infection spreads from person to person through everyday contact. The virus is most often spread by sharing food or drink with an infected person or by getting droplets containing the virus on your hands and then touching your eyes, nose, or mouth. The incubation period—the time from exposure to RSV until you develop symptoms—ranges from 2 to 8 days, but usually is 4 to 6 days.
There are two types of RSV, as well as multiple subtypes (strains). Therefore, the body does not develop complete immunity to the virus, and infection can occur repeatedly throughout life, sometimes even during the same season.