When might genital herpes testing be appropriate?

Q. How do you test for genital herpes?

A. You can test for genital herpes by swabbing a genital or anal sore, blister, or ulcer and studying it in the laboratory, or by testing for antibodies in the blood.

Genital herpes is caused by the herpes simplex virus (HSV). There are two types: HSV-1 and HSV-2. HSV-1 more commonly causes oral infections (cold sores) and HSV-2 more commonly causes genital herpes. But both types can affect the mouth or anogenital area.

People who have never had oral HSV-1 infections can get HSV-1 genital herpes through oral sex with someone who has an oral HSV-1 infection. The transmission of herpes from one person to another tends to occur quickly in new relationships.

An estimated 15% of sexually active Americans have been infected with genital herpes. Most of them never know they have been infected because they either have no symptoms or they have mild sores and don't seek medical evaluation. But even without symptoms, they can pass the infection on to their sexual partners. Some people who become infected with genital herpes develop recurrent symptoms.

If you get a genital sore, blister, or ulcer, your doctor can swab it and send the specimen to the lab. It will be tested for HSV-1 or HSV-2.

You can also tell if you are infected with herpes through blood testing. Antibodies develop within a few weeks after a person becomes infected with herpes, and they persist for life. A blood test can distinguish between HSV-1 and HSV-2. The presence of HSV-2 antibodies usually indicates a genital or anal infection, but HSV-1 antibodies can be due to either oral infection or genital infection.

Routine screening for HSV antibodies is not recommended. The decision to do any testing for HSV depends upon a person's individual circumstances.

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