Translations:Common cold/10/en

Causes

Viruses

Coronaviruses are a group of viruses known for causing the common cold. They have a halo or crown-like (corona) appearance when viewed under an electron microscope.

The common cold is an infection of the upper respiratory tract which can be caused by many different viruses. The most commonly implicated is a rhinovirus (30–80%), a type of picornavirus with 99 known serotypes. Other commonly implicated viruses include adenoviruses, enteroviruses, parainfluenza and RSV. Frequently more than one virus is present. In total, more than 200 viral types are associated with colds. The viral cause of some common colds (20–30%) is unknown.