You might call them cold sores or canker sores or maybe fever blisters. Whatever they're called in your house, if you get them, you're in the company of about ninety-five million other Americans who suffer from the virus that causes cold sores.

Herpes Simplex

The scientific name for this virus is herpes simplex, type one. Although it is a relative of herpes simplex two, more commonly known as genital herpes, its effects are usually less serious.

Virus Remains Hidden

As soon as this herpes virus begins producing a cold sore, the body's immune system manufactures antibodies and white blood cells to combat the virus.

The immune system may be able to win the battle against an individual cold sore, but it can never win the war against the virus that causes the cold sore. Even after the cold sore is completely healed, the virus remains hiding in the body in a resting, or latent phase.

If triggered, this latent virus will begin the cycle again and cause another outbreak.

Never Far Away

In fact, recurrence of these painful cold sores is very common because once you have the virus, you never get rid of it. The latent virus can be triggered by many factors.

Exposure to wind and sun can cause an outbreak, and so can physical or emotional stress. Many people who have the virus get a blister every time they come down with a cold because their immune systems get overloaded and can't attend to everything at once.

Infected As Children

Some people never get cold sores because they have never been infected with the virus, which you can get through direct contact with the lips or mouth of a person with an active sore.

Researchers believe that most people were infected as children when an adult with a cold sore kissed them.

Read More: Dorland's Illustrated Medical Dictionary (Amazon), The Merck Manual of Diagnosis and Therapy (Amazon), and Stedman's Medical Dictionary (Amazon)