Genital herpes is a sexually transmitted infection (STI) that causes blisters and ulcers. It is caused by the herpes simplex virus (HSV), which is passed on through skin-to-skin contact.
Herpes can affect various areas of the body but is most commonly found on the genitals, anus or mouth. The blisters heal with time, but the virus that causes them cannot be cured. Herpes outbreaks will often reoccur.