Health Topics A-Z

What Is Genital Herpes?

Herpes is the most common sexually transmitted virus in the U.S. More than 45 million people in the U.S. — one in five adults and adolescents — carry the virus. It's highly contagious and incurable, but you can learn to live with it.

Genital herpes can cause fatal infections in newborns if the mother is shedding virus at the time of delivery. The virus also makes it easier for a person to transmit and get HIV and other sexually transmitted diseases.

What Causes It?

A virus called herpes simplex virus (HSV) causes herpes. HSV type 2 or HSV-2 is the most common cause of genital herpes. HSV-1, which causes the "cold sores" or "fever blisters" many people get on their lips, can also cause genital herpes.

The virus can be spread through both vaginal and anal intercourse as well as by oral sex. The virus is spread most easily by coming into contact with a herpes ulcer. However, the virus can also be spread from an infected person who does not have ulcers-this is referred to as asymptomatic shedding.