This negatively-stained transmission electron micrograph (TEM) revealed the presence of numerous herpes simplex virions, members of the Herpesviridae virus family. There are two strains of the herpes simplex virus, HSV-1, which is responsible for cold sores, and HSV-2, which is responsible for genital herpes. CDC image by Dr. Fred Murphy
WASHINGTON, Aug. 6 (UPI) -- An experimental gel meant to curb the sexual transmission of the human immunodeficiency virus, or HIV, was found to cut the chances of a woman contracting herpes by half, according to a new study.
The gel's active ingredient, tenofir, has been the subject of several studies on its efficacy against HIV, finding that it was often ineffective for that use, partially because of inconsistent use. In pill form, the drug is already used to treat HIV and has been tested for use against herpes simplex virus type 2.
The gel, which has a higher concentration of tenofir than the pill, is meant to be applied vaginally before and after sex, making proper use of it key to preventing the spread of any disease.
"How people use it is important," Dr. Connie Celum, a professor at the University of Washington, told HealthDay. Celum, who conducted a study on the pill form of the drug last year, found it had a some benefits in preventing the spread of herpes. "We don't have a cure for HSV-2, and we don't have a vaccine," making the gel a "promising intervention that could reduce herpes acquisition."
The new study, published in the New England Journal of Medicine, was conducted in South Africa by the Center for the AIDS Program of Research in South Africa.
Researchers recruited 422 women without herpes, randomly giving them tenofir gel or a placebo. Among the 202 people given the drug, 10.2 new cases of herpes per 100 people were found. The group that received the placebo saw 22.1 new cases per 100 people, showing a 51 percent drop in herpes transmission during the 18-month study.
Previous studies have shown the gel to have a 39 to 54 percent range of efficacy in preventing the spread of HIV as well, however the researchers found that inconsistency in application of the gel calls into question how effective it can be.
Further studies will be done on the drug for use against the spread of both herpes and HIV, including vaginal rings and other contraceptives that include it in order to improve patient adherence to instructions for use, researchers said.
