amfAR, The Foundation for AIDS Research

Treating Herpes Doesn’t Decrease Risk of HIV Infection

February 20, 2008—Although doctors have known for some time that sexually transmitted infections such as genital herpes make people more susceptible to HIV, new research indicates that treating the infection does not decrease the risk of contracting HIV.

Genital herpes, which infects an estimated 45 million people in the U.S. alone, is known to substantially increase the risk of HIV infection. Some have hypothesized that the open blisters associated with this infection provide an entryway into the body for HIV.

Speaking at the 15th Conference on Retroviruses and Opportunistic Infections in Boston, held February 3–6, Dr. Connie Celum of the Fred Hutchinson Cancer Research Center in Seattle reported the results of a study of more than 3,000 volunteers with herpes simplex 2. Half were given the antiviral drug acyclovir and half took a placebo in an attempt to see if treating genital herpes reduced the risk of HIV infection.

“The answer was no. It is a disappointment,” said Dr. Rowena Johnston, vice president of research for amfAR, in a Reuters interview.

But Dr. Johnston suggested that it was possible that the drug did not work well, or that subjects had lower than optimal adherence and did not take their recommended dosage regularly enough to combat the herpes virus.

“We know the acyclovir was somewhat effective [in treating herpes],” said Dr. Johnston. “The patients must have been taking their medication somewhat steadily since herpes outbreaks were reduced.” But she added that newer herpes drugs are more effective. She also posited that the herpes virus, a permanent infection, may be responsible for keeping immune cells in a constant state of activation. “If you have an ongoing immune reaction in your genital tract it is possible you have an ongoing increased risk of acquiring HIV,” she said.

Finding new ways to stop the spread of HIV continues to confound researchers. Although disappointed with the outcome of what had been a promising study, researchers continue to look into other methods of slowing the spread of HIV/AIDS.