Many people aren't aware of how widespread the herpes virus really is.

In fact, according to a World Health Organization (WHO) report, two thirds of all people under the age of 50 (3.7 billion people worldwide) are infected with herpes simplex virus type 1 (HSV-1), a virus commonly linked with cold sores.

Mashable reports:

"The burden of infection varies in different parts of the world and between men and women, according to the report [which was released on October 28 in the journal PLOS One]. In the Americas, about 39% of all women are infected and 49% of men. In the Eastern Mediterranean, 75% of both men and women are infected and 87% of both men and women are infected in Africa."

"And that's just men and women under age 50. Above this age, the burden of infection would probably 'trend toward 100%' in many places, says Bryan Cullen, director of the Duke University Center for Virology, although the WHO study doesn't include these statistics.

"HSV-1 is the same virus most commonly responsible for causing skin lesions, or 'cold sores,' around the mouth, a disease that can be transmitted via skin-to-skin contact, such as kissing. But while cold sores are a mostly cosmetic issue, there's good reason to collect data on the virus, argue some experts."

Furthermore, the research suggests that HSV-1 may be progressively more responsible for genital herpes. Not only that, but this virus has also been known to cause infections that can lead to blindness and rarely, encephalitis.

HSV-1 is just one of the two forms of the herpes simplex virus. The other, called HSV-2, has been associated with genital herpes. In fact, it is "almost exclusively sexually transmitted."

HSV-2 infections pose more adverse dangers to people. The virus has been found to increase a person's risk of contracting HIV.