WEDNESDAY, Dec. 1, 2004 (HealthDayNews) -- Just in time for World AIDS Day, researchers in San Francisco announced they are investigating whether a common herpes drug could combat the spread of HIV by making patients less susceptible to the AIDS virus.
The theory is that, by taking the herpes drug Acyclovir all the time, instead of just during outbreaks or not at all, patients would keep their herpes under better control and, at the same time, make their bodies less vulnerable to HIV infection.
Unlike many other AIDS prevention treatments that are in the research pipeline, Acyclovir could quickly make its way to people at risk of HIV infection because the drug is already on the market, said Dr. Susan Buchbinder. She is director of HIV research for the San Francisco Department of Public Health, which is taking part in the year-long study.
"If this were found to be a safe and effective prevention strategy, a number of groups would work to make this available globally," she said.
Meanwhile, the U.S. Centers for Disease Control and Prevention on Wednesday issued some good and bad news to mark the AIDS fight on World AIDS Day.
Rates of HIV/AIDS diagnoses remained fairly stable from 2000 to 2003 in 32 states where statistics are available, according to a report in the CDC's Morbidity & Mortality Weekly Report, which was released Dec. 1. However, diagnoses did go up by 5 percent among men, apparently because of increases in cases affecting gay and bisexual males.
The CDC also reported that about 10 percent of Americans aged 18 to 64 reported being tested for HIV in the previous year.
While diseases like AIDS usually get more attention, genital herpes is much more common. According to the CDC, an estimated 18 percent of Americans aged 14 to 49 are infected with herpes simplex virus type 2, the most common cause of genital herpes.
Many of those infected take Acyclovir -- which is prescribed an estimated 4.4 million times a year in North America -- during herpes outbreaks. However, herpes can sometimes be transmitted when infected people don't realize they're contagious. Also, the disease makes people more susceptible to HIV infection, and may have more impact on the AIDS epidemic than any other sexually transmitted disease, Buchbinder said.
Herpes appears to contribute to the transmission of HIV by creating genital ulcers that break down the mucous barriers that provide protection against germs. Even small "micro lesions," which don't produce noticeable symptoms, could make it easier for the AIDS virus to get through, Buchbinder said.
Herpes creates another problem: When people have herpes outbreaks, the immune system dispatches white blood cells to the affected area.
"They're the very cells that HIV infects," Buchbinder said. Along with the disruption of mucous barriers, "it's kind of a double whammy. You've got a breakdown of the normal immune response, and you're mobilizing those cells that HIV attacks."
Participants in the study will be randomly assigned to take either Acyclovir or a placebo on a regular basis; they will all take Acyclovir when they have herpes outbreaks. The drug has few side effects and, at about $30 to $40 a month, it's fairly inexpensive, Buchbinder said.
More information
To learn more about new AIDS studies in San Francisco, visit the city's Department of Public Health.
