You probably have herpes, the WHO says

By Tom Miles GENEVA (Reuters) – Two-thirds of the world’s population under 50 have the highly infectious herpes virus that causes cold sores around the mouth, the World Health Organization said on Wednesday, in its first estimate of global prevalence of the disease. More than 3.7 billion people under the age of 50 suffer from the herpes simplex virus type 1 (HSV-1), usually after catching it in childhood, according to a the WHO study. HSV-1 normally causes mouth ulcers rather than genital infection, but it is becoming an increasing cause of genital infection too, mainly in rich countries.
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