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Lack of symptoms no protection against herpes

April 12, 2011 12:00:00 AM PDT
It's a study researchers hope will raise awareness about one of the most common sexually transmitted diseases.

Many people think herpes is only contagious if someone is showing symptoms. But a new study suggests that's not the reality. People should always be aware.

Researchers are beginning to understand that you don't have to have symptoms or flare-ups to be contagious.

"Many people think with genital herpes infections that they can only spread the virus when they have symptoms," said Dr. Anna Wald, University of Washington.

That is not true. In a report provided by the Journal of the American Medical Association, doctors studied almost 500 people, some with recurring genital herpes with symptoms, and others who tested positive for HSV-2 but had no clinical signs. They were monitored for 30 days to assess how often the virus was active.

"When we take people who are HSV-2 positive, so they have [the] antibody but they don't have any history of genital herpes, still the virus is active on about 10 percent of the days in most of these persons," said Dr. Christine Johnston, University of Washington.

"So even people without a clinical history of genital HSV-2 are capable of spreading the virus to sexual partners," said Wald.

It's information people can use in counseling patients who have been diagnosed.

Researchers also found people who had recurring genital herpes symptoms had the active virus on about 20 percent of days.