Two types of the herpes simplex virus (HSV) can cause cold sores. The majority of cold sores come from type 1 HSV. Type 2 HSV usually triggers sores in the genital area. However, both types can cause the sores in both areas. Although cold sores are always a symptom of HSV type 1 or 2, there are many different routes of cold sore transmission.


1. Dormant Virus

Approximately 90% of the adult population carries the herpes simplex virus, which can remain dormant and never cause a cold sore. Alternatively, however, some people experience recurring cold sores. A fever or viral infection can activate a dormant virus, as can changes in hormones or the immune system, stress, fatigue, and sun and wind exposure.

herpes cold sore transmission

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