9 doctors weighed in:
What causes cold sores?
9 doctors weighed in

Dr. Dinh Bui
Dentistry
5 doctors agree
In brief: Herpes simplex virus
Oral herpes, occurs with symptoms of cold sores or fever blisters, is an infection of the mouth and cause by herpes simplex virus type 1 and type 2.
After initial infection, the viruses are transported to the sensory nerve cell bodies, where they become latent and reside lifelong. Upon trigger, these virus then multiplies new virus particles, transport, and releases to the nerve terminal.

In brief: Herpes simplex virus
Oral herpes, occurs with symptoms of cold sores or fever blisters, is an infection of the mouth and cause by herpes simplex virus type 1 and type 2.
After initial infection, the viruses are transported to the sensory nerve cell bodies, where they become latent and reside lifelong. Upon trigger, these virus then multiplies new virus particles, transport, and releases to the nerve terminal.
Dr. Dinh Bui
Dr. Dinh Bui
Thank
1 comment
Dr. Sami Latif
Can be dormant in the body for up to 25 years , this virus has many strains , some of them can lead to cancer
Dr. Robert Kwok
Pediatrics
1 doctor agrees
In brief: Herpes virus returns
Cold sores on the lips or near the lips, are usually caused by recurrent oral herpes virus.
They start as a slightly raised reddish area, then form a cluster of tiny blisters, which break open soon, leaving a sore (ulcer) to heal up over a week. Sores appear more often when one is under stress or is ill from another illness. Younger babies with herpes should see a doctor when a sore appears.

In brief: Herpes virus returns
Cold sores on the lips or near the lips, are usually caused by recurrent oral herpes virus.
They start as a slightly raised reddish area, then form a cluster of tiny blisters, which break open soon, leaving a sore (ulcer) to heal up over a week. Sores appear more often when one is under stress or is ill from another illness. Younger babies with herpes should see a doctor when a sore appears.
Dr. Robert Kwok
Dr. Robert Kwok
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Dr. Richard Ruden
Dentistry
In brief: Herpes virus
Cold sores are caused by the herpes simplex virus (hsv).
There are two types of herpes simplex virus: hsv-1 and hsv-2. Both virus types can cause sores around the mouth (herpes labialis) and on the genitals (genital herpes).

In brief: Herpes virus
Cold sores are caused by the herpes simplex virus (hsv).
There are two types of herpes simplex virus: hsv-1 and hsv-2. Both virus types can cause sores around the mouth (herpes labialis) and on the genitals (genital herpes).
Dr. Richard Ruden
Dr. Richard Ruden
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