AIDS 30th Anniversary (VIDEO)

After 30 years, there are reasons to be optimistic about the fight against HIV and AIDS.

This weekend marks the 30th anniversary of the disease's discovery. The number of people living with HIV continues to increase, but in some ways, that shows progress is being made to combat the disease.

With the help of early treatment and antiretroviral therapy, many HIV patients go on to live into old age, according to the Center for Disease Control and Prevention.

For those, like retired nurse Kate Ratcliff, who remember the early days of the disease, that's a marked change from 30 years ago.

"It was frightening," Ratcliff said of the disease's first years. "[It was] upsetting and terribly, terribly sad."

But Timothy Brown provides even more hope for those seeking to finally conquer HIV and AIDS. He received a blood stem cell transplant to treat his leukemia in 2007. It not only cured his leukemia, it got rid of his HIV as well.

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