14 doctors weighed in:

What causes cold sores?

14 doctors weighed in
Dr. Michael Reilly
Surgery - Plastics
7 doctors agree

In brief: Virus reactivation

Cold sores are caused by reactivation of a latent ("sleeping") virus in the nerves that supply sensation to the inside of the mouth.
This is a "herpes" virus, but is most often not the same virus as the one that causes genital herpes. After contracting the virus from someone else's oral cavity, the virus can be reactivated by various triggers, including a common cold or other stressors.

In brief: Virus reactivation

Cold sores are caused by reactivation of a latent ("sleeping") virus in the nerves that supply sensation to the inside of the mouth.
This is a "herpes" virus, but is most often not the same virus as the one that causes genital herpes. After contracting the virus from someone else's oral cavity, the virus can be reactivated by various triggers, including a common cold or other stressors.
Dr. Michael Reilly
Dr. Michael Reilly
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Dr. Carla Enriquez
Pediatrics
1 doctor agrees

In brief: Slow virus

Herpes simplex virus causes an acute infection in childhood.
Then it can become a dormant virus in some people that produces cold sores when it is reactivated by an insult to the immune system. The insult could be another infection, sun light, stress, or barotrauma.

In brief: Slow virus

Herpes simplex virus causes an acute infection in childhood.
Then it can become a dormant virus in some people that produces cold sores when it is reactivated by an insult to the immune system. The insult could be another infection, sun light, stress, or barotrauma.
Dr. Carla Enriquez
Dr. Carla Enriquez
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Dr. Harlan Wilson
Dentistry
1 doctor agrees

In brief: Cold sores

The cause of cold sores is debillitation.
If you were previously sick, overworked yourself through over exercise, or work, if you have been through a surgery your body mechanisms for self defense have been compromised. Cold sores are viruses that are always with you and normally cause no harm except when they can take advantage of your compromised situation.

In brief: Cold sores

The cause of cold sores is debillitation.
If you were previously sick, overworked yourself through over exercise, or work, if you have been through a surgery your body mechanisms for self defense have been compromised. Cold sores are viruses that are always with you and normally cause no harm except when they can take advantage of your compromised situation.
Dr. Harlan Wilson
Dr. Harlan Wilson
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David Miller
Family Medicine
1 doctor agrees

In brief: Herpes virus

Cold sores are typically caused by the type i herpes virus.
It is very common and distinct from genital herpes, which is typically caused by the type ii herpes virus, although there is some overlap between the two.

In brief: Herpes virus

Cold sores are typically caused by the type i herpes virus.
It is very common and distinct from genital herpes, which is typically caused by the type ii herpes virus, although there is some overlap between the two.
David Miller
David Miller
Answer assisted by David Miller, Medical Student
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1 comment
David Miller
It's such a common th
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