Study find HIV drugs already in use can cut risk of infection in couples.
New AIDS research could change the way HIV-infected patients are treated as medications are found to curb the spread of the virus dramatically.
Treating HIV-infected men and women with anti-retroviral drugs sooner rather than later can reduce the likelihood they will pass the virus to uninfected sexual partners by 96-percent.
This result of a large, international clinical trial was so significant researchers interrupted the study years before it was supposed to end so all participants could benefit.
"Patients were healthier; fewer infections, and most importantly there was a very dramatic reduction of transmission of HIV from the infected person to their sexual partner," says Dr. Myron Cohen of the University of North Carolina, the study's lead researcher.
More than 1,700 sexually active couples participated and were split into two groups.
In one, the infected partner started taking a combination of anti-retroviral drugs immediately.
In the second group, the patient waited to take the medicine until they experienced certain symptoms or effects of the virus.
"They were counseled about safer sex, and they were provided free condoms and we did everything in our power to reduce the probability of a transmission," notes Dr. Cohen.
There was only one case of HIV transmission in the group that started immediate treatment.
There were 27 in the delayed treatment group.
Those infected also had fewer HIV-related illnesses when they started taking the drugs immediately.
Anti-retroviral treatment is a life-long committment; once you start it, you really can't stop.
It's costly and can come with side effects.
Still, this shows when treatment comes early the benefits extend to both the patients and their partners.
Nearly all of the couples were heterosexual, so experts say this news can not be applied to same-sex couples.