Herpes is an infection that is caused by a herpes simplex virus (HSV). Oral herpes causes cold sores around the mouth or face. Genital herpes affects the genitals, buttocks or anal area. Genital herpes is a sexually transmitted disease (STD). You can get it from having sex, even oral sex. The virus can spread even when sores are not present. Mothers can also infect their babies during childbirth.
Some people have no symptoms. Others get sores near the area where the virus has entered the body. They turn into blisters, become itchy and painful, and then heal. The virus can be dangerous in newborn babies or in people with weak immune systems.
Most people have outbreaks several times a year. Over time, you get them less often. Medicines to help your body fight the virus can help lessen symptoms and decrease outbreaks. Correct usage of latex condoms can reduce, but not eliminate, the risk of catching or spreading herpes.
MedlinePlus - Herpes Simplex