Upper respiratory tract infection causes

Overview
Upper respiratory infections, commonly referred to the acronym URI or URTI, is the illness caused by an acute infection which involves the upper respiratory tract: nose, sinuses, pharynx or larynx. In the United States, this represents approximately one billion acute upper respiratory illnesses annually.

Causes of upper respiratory tract infection
You can catch a cold if: People are most contagious for the first 2 to 3 days of a cold. A cold is usually not contagious after the first week.
 * A person with a cold sneezes, coughs, or blows their nose near you
 * You touch your nose, eyes, or mouth after you have touched something contamined by the virus, such as a toy or doorknob.