One in five Americans has genital herpes, but many don't know it because the symptoms can be mild or even absent. But you don't have to have a sore to give the virus to another person.
Genital herpes is usually spread by sexual contact and caused by the type 2 herpes virus (HSV-2). Occasionally, an infected person "sheds" infectious virus without obvious signs of an outbreak.
However, the type 1 herpes virus (HSV-1), which more commonly causes cold sores, can also infect the genitals -- usually through oral sex. That's why it is especially important to get tested -- to help prevent spreading the infection.
When there's a genital herpes outbreak, a doctor can swab the sores to check for the herpes virus.
The sooner the swab is taken after an outbreak starts, the better the chances of the test being accurate.
The common way to find out whether you've got the virus is through genital herpes blood tests.
Genital herpes blood tests show whether you have herpes -- and whether it's type 1 or type 2.
Blood samples are usually used to see if the immune system has produced antibodies against the herpes virus.
Results take several days and only tell that you have been exposed to the virus at some point.