Say: RES-pur-uh-tor-ee sin-sish-EE-ul VY-rus
This infection (also called RSV) of the lungs and breathing passages is caused by a virus. RSV is very common in little kids. It's also very contagious.
When babies get RSV, it can make it hard for them to breathe. Older kids who get RSV usually just have the same symptoms as a cold. Kids who have RSV need to rest and drink lots of fluids to get better.