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 dried 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 with 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 four to six days after exposure. Symptoms generally develop slowly over a period of several days.