Genital herpes is one of the most common sexually transmitted infections. It is caused by the herpes simplex 2 virus, and affects approximately 16 percent of American adults or about 40 million people. Until recently, scientists did not know whether a person without any apparent genital sores could spread the virus to a partner. A new study of nearly 500 individuals whose blood tests showed they carried the virus has found that virus is shed even when there are no active lesions. People who would not have known they were infected, but for the positive blood test, were shedding virus on at least one day out of ten. People with symptomatic herpes shed virus 20 percent of the time.
What does this mean for people with herpes? To prevent the spread of the virus the researchers recommend condom use, daily anti-viral drug treatment with a medication like Valtrex, and telling all partners about carrier status. Each of these tactics can cut transmission in half, though none of these alone can completely protect a partner.
[JAMA, April 13, 2011]