Herpes affects two-thirds of people under 50, WHO says

Herpes simplex virus type 1, which causes cold sores around the mouth, is present in more than 3.7bn people, says organization amid push for vaccine

Two-thirds of the world's population under 50 have the highly infectious herpes virus that causes cold sores around the mouth, said the World Health Organization 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 WHO study published on Wednesday.