The common cold is an extremely contagious upper respiratory viral illness. The common cold virus is easily spread when a live virus enters the body through the nose, mouth or eyes. One method of transmission is to directly inhale the virus when it is air-borne after an infected person sneezes or coughs. Another of the ways that it spreads is from touching an infected, or contaminated, surface and then touching the nose, eyes or mouth. The common cold virus is most contagious during the first few days of illness and before a person knows they are infected, making it difficult to prevent.
The common cold virus is one of the most easily spread infections, and there are more than 200 different viruses, known as rhinoviruses, that cause this illness. In order for a person to catch a cold, the virus needs to enter the body, usually through the nose, mouth or eyes. The virus quickly starts multiplying and causing symptoms once it enters the body; the first signs of illness often occur within days, such as a stuffy or runny nose. The secretions, or mucus, from the nose and the saliva are usually heavily infected with common cold virus.
Every time a person with the common cold virus coughs or sneezes millions of tiny drops of infected moisture are released into the air. One way to catch the virus is to be nearby and breathe in air that contains these infected droplets. An easy way to prevent this is to always sneeze or cough into the bend of an elbow or a tissue, which can stop a lot of the virus from becoming air-borne and being spread through the air.
Usually, the most common way the common cold virus is spread is when a person touches his or her mouth, eyes or nose after touching a surface that the virus has contaminated. Surfaces can become contaminated when moisture containing the virus lands on them or when an infected person spreads it through contact with his or her hands. The virus can live on surfaces such as doorknobs, keyboards, telephones and utensils for several hours, potentially infecting anyone who touches them afterward. Hand-to-hand contact with an infected person is another common method of transmission.
A few ways to combat the spread of the common cold virus are to wash hands frequently, avoid touching the face, and to thoroughly clean surfaces with which many people come into contact on a regular basis. These precautions should be followed at all times since it's possible for infected people to spread the virus before they show symptoms of illness. The first few days of illness are when a person is most contagious, so extra caution should be used when exposed to someone with a known case of the common cold as well.