Genital Herpes Infection Active Even Without Symptoms

< Apr. 13, 2011 > -- Genital herpes can be passed on to others even when the infected person has no symptoms.

Although researchers suspected that this was possible, a new study of about 500 people infected with the herpes simplex virus confirms that it's true.

Herpes simplex type 2 is one of the most common sexually transmitted diseases. In the U.S., 16 percent of adults have tested positive for the HSV-2 virus, but many more may be infected and not know it.

"Most people don't know they have it," says Fred Wyand, at the American Social Health Association.

Common symptoms

One reason is that not everyone with HSV-2 infection has symptoms, and even when people have symptoms, they may blame them on other conditions, such as jock itch or a yeast infection. Common symptoms of HSV-2 infection include itching, burning, or pain in the genital area; visible blisters; swollen glands in the genital area; fever; lower back, buttock, or leg pain; and vaginal discharge.

For the study, published in this week's issue of the Journal of the American Medical Association, participants took genital swabs daily for at least a month. More than 28,000 swabs were collected and analyzed.

The virus was detected on 20 percent of the days in 410 people who had symptoms, compared with 10 percent of the days in those who had no obvious symptoms.

But both groups shed about the same amount of virus on the days they were shedding. Shedding refers to the times when the virus is replicating and therefore is able to be passed on to another person.

Prevention important

Study co-author Christine Johnson, M.D., says the study results should encourage people who are infected with HSV-2 to use preventive measures as often as possible. Those include wearing a condom when having sex, taking the antiviral medication valacyclovir every day, and telling any sexual partners about the infection.

"All of those three strategies have been shown to reduce transmission by 30 to 50 percent," Dr. Johnston says.

Protect Yourself from STDs

The only sure way to protect yourself from sexually transmitted diseases (STDs) is not to have sex. If you do have sex, here is how you can lower your risk:

• Use a male latex or female polyurethane condom and topical microbicides consistently and correctly.
• Have regular checkups for HIV and STDs.
• Limit your partners. The more partners you have, the higher your risk for STDs.
• Have a mutually monogamous sexual relationship with an uninfected partner.
• Delay having sexual relationships as long as possible--the younger a person is when he or she begins having sex, the more susceptible the person becomes to developing an STD.
• Avoid anal intercourse, or use a male latex condom and topical microbicides.
• Avoid having sexual intercourse during menstruation.
• Avoid douching.
• Get to know your partner first. Has your partner ever had sex without a latex condom? How many previous partners has he or she had? Has your partner ever had an STD, and if so, has it been cured?
• If your partner has any STD warning signs, don't have sex until he or she has been checked by a doctor. If you have had sex already, see your doctor, too.

Always talk with your health care provider to find out more information.