Bronchiolitis is one of the most common lung diseases in children and babies during winter. It is transmitted through air. Normally, it is caused by a virus that swells the small airways up. It starts out with symptoms similar to those of a common cold, but it is normal to cough, hear a whistling noise when the child breathes out or have some difficulties breathing.

These symptoms last several days, weeks or even a month. For the first few days, it is normal to have a stuffy nose and, in some cases, slight fever. Some children will also have an ear infection.