The first Aids, or acquired immune deficiency syndrome, cases were reported in the United States in 1981. But so far, only one person has been cured of human immunodeficiency virus (HIV).
That is 49-year-old American Timothy Ray Brown, who is also nicknamed "The Berlin Patient".
Mr Brown, who is homosexual, found out he was HIV-positive in 1995, while attending school in Berlin, Germany.
HIV causes Aids.
Just over a decade later, he was diagnosed with acute myeloid leukaemia, a form of cancer.
After chemotherapy failed, a blood cancer specialist had recommended a bone marrow transplant, using bone marrow from someone with a natural genetic mutation known to be resistant to HIV.
The mutation disables the CCR5 gene, which is like a door handle to a person's immune system cells. By doing so, the HIV has no way of infecting the cells.
Mr Brown underwent the transplant in 2007, and also stopped taking his antiretrovirals.
His HIV has not returned, and in July 2012, he formed the Timothy Ray Brown Foundation - now called the Cure For Aids Coalition - dedicated to fighting HIV and Aids.
He had said: "I'm the proof in concept that a cure for HIV is possible...
"I want to give people hope that medical science would be able to come up with a cure."
This article was first published on Nov 20, 2015.
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