SEE WHAT KISSING HAVE DONE TO ME..AFTER READING THIS YOU WILL NEVER KISS AGAIN..

Cold Sores (Fever Blisters)

Herpes labialis (cold sore) is caused by the herpes simplex virus. Cold sores commonly appear on the edge of the lip. This virus exists in a dormant state in the spinal cord nerve cells, and after certain environmental triggers like a sunburn or a cold, the virus is induced to travel along a peripheral nerve to the same skin site over and over again. The eruption is self-limited to about seven to 10 days so that treatment is unnecessary unless the eruption becomes too frequent.

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