Scientists may have created a vaccine that could cure someone who has already been infected with the HIV/AIDS virus.

The vaccine was tested on a non-human primate version of the virus called simian immunodeficiency virus (SIV), which can lead to AIDS in monkeys, an Oregon Health and Science University press release reported.

"To date, HIV infection has only been cured in a very small number of highly-publicized but unusual clinical cases in which HIV-infected individuals were treated with anti-viral medicines very early after the onset of infection or received a stem cell transplant to combat cancer," Louis Picker, M.D., associate director of the OHSU Vaccine and Gene Therapy Institute, said. "This latest research suggests that certain immune responses elicited by a new vaccine may also have the ability to completely remove HIV from the body."

The researchers employed a common virus called CMV to help with the vaccine. When they modified CMV it "generates and indefinitely maintains so-called "effector memory" T-cells that are capable of searching out and destroying SIV-infected cells," the press release reported.

About 50 percent of the monkeys that were infected with SIV fell ill for a short period of time and then cleared the virus from their system completely with the help of the vaccine.

"Through this method we were able to teach the monkey's body to better 'prepare its defenses' to combat the disease," Picker said. "Our vaccine mobilized a T-cell response that was able to overtake the SIV invaders in 50 percent of the cases treated. Moreover, in those cases with a positive response, our testing suggests SIV was banished from the host. We are hopeful that pairing our modified CMV vector with HIV will lead to a similar result in humans."

The lab is now working to figure out why only half of the monkeys had this response to the vaccine.

The fight to cure HIV/AIDS has been long-winded. The "Man Who Can't Catch AIDS," Stephen Crohn, recently committed suicide at the age of 66 after suffering what was believed to be "survivor's guilt," the New York Daily News reported.

The man lost many close friends and even his partner to the virus, but was never infected himself due to a mutation in his white blood cells.

Crohn participated in studies during his lifetime that helped researchers understand how AIDS spreads throughout the body.

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