4 doctors weighed in:

What is the cause of cold sores?

4 doctors weighed in
Dr. Steve Krendl
Dentistry
2 doctors agree

In brief: Direct Contact

Cold sores are caused by the herpes simplex virus (hsv).
They are typically transmitted through broken skin. Sometimes through kissing, sharing eating utensils or drinking cups, or other forms of touching another person's saliva.

In brief: Direct Contact

Cold sores are caused by the herpes simplex virus (hsv).
They are typically transmitted through broken skin. Sometimes through kissing, sharing eating utensils or drinking cups, or other forms of touching another person's saliva.
Dr. Steve Krendl
Dr. Steve Krendl
Thank
Dr. Robert Kwok
Pediatrics

In brief: Herpes virus, return

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, return

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
Thank
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