AIDS claimed a string of celebrity victims in its early days, from Rock Hudson to Freddie Mercury, but fellow stars have played a major role in fighting the killer disease over the years since.
Elton John and Elizabeth Taylor were among leading figures who used their celebrity from the start to raise awareness and funds for research into HIV, as well as reducing the stigma of what was initially seen as a "gay plague."
Retired basketball player Magic Johnson has campaigned tirelessly since announcing in 1991 that he had contracted HIV, while pop icon Michael Jackson, a friend of Taylor's, was also a strong supporter before his death in 2009.
John's "White Tie and Tiara Ball" has become an annual star-studded fixture organized with his partner David Furnish since 1999 to raise funds for his Elton Joects in 55 countries since it was founded in 1992.
"Both Elton and David are absolutely passionate about the work of the Foundation. They are on the phone weekly getting updates ... and discussing stategy," said Anne Aslett, boss of EJAF's British arm.
"Celebrities can speak personally and emotionally ... This means their influence can be enormous," she told AFP, citing the impact of others including the late Princess Diana, Whoopi Goldberg and Sharon Stone.
AIDS first came to broad public notice in 1981, when US doctors noted an unusual cluster of deaths among young homosexuals in California and New York.
In the three decades since then it has killed nearly 30 million people, and 33 million others live with it or HIV, the virus that causes AIDS by destroying immune cells, according to 2009 World Health Organization (WHO) figures.
The first major celebrity victim was Hudson, whose admission that he was suffering from HIV in the early 1980s helped raise the profile of the disease. He died in 1985, aged 59.
Flamboyant US entertainer Liberace died in 1987 followed in 1990 by Scottish "Chariots of Fire" actor Ian Charleson and New York artist Keith Haring, who was only 31 when he died.
Queen frontman Mercury died the following year, perhaps the first high-profile pop star to succumb publicly to the disease. Jacques Morali, creator of camp music icons the Village People, died the same year.
Also in 1991 Oscar-winning British director Tony Richardson died, while Magic Johnson announced he was HIV positive, retired immediately and dedicated his life to fighting the deadly disease.
In 1992 "Psycho" actor Anthony Perkins, Britain's Denholm Elliott and sci-fi writer Isaac Asimov all died, followed by tennis star Arthur Ashe and ballet dancer Rudolf Nureyev in 1993.
The list of high profile AIDS victims has tailed off as awareness grew and more effective treatments were introduced -- at least in rich developed countries -- but celebrity campaigners kept fighting.
Screen siren Taylor, who died in March aged 79, regularly organized AIDS fund-raising benefits until her own health complications mounted.
"She saw this terrible disease, and she was angered by the fact that nobody was doing anything about it," said Kevin Frost, head of the Foundation for AIDS Research (amfAR), co-founded by Taylor in 1985.
"She just stepped right into the breach."
Magic Johnson, 51, was one of the first to benefit from the cocktail of antiretroviral medications which emerged in the mid-1990s to keep HIV in check -- and he believes his infection and survival were meant to be.
"This happened to me for a reason, and I know it was for me to help someone else," he said in an interview in Newsweek magazine ahead of the HIV anniversary.
But he is concerned that, while gays have taken steps to protect themselves, African Americans still treat the subject as taboo -- the HIV infection rate for black women was 15 times that for white women, according to 2006 figures.
"Those numbers really break my heart... The gay community has done such a great job of getting their message across, and it?s worked, But there is still such a stigma with the virus in our community, and that prevents any progress."
Some groups who benefit from celebrity funding play down the importance of star power, saying staying power is more important.
"In the world of AIDS advocacy, Elton is seen less as a celebrity and more as one of the real leaders in the fight," said Drew Altman of the Kaiser Family Foundation, one of dozens of groups backed by Elton John's Foundation.
"When he gets involved he sticks with it when others show only temporary interest," he told AFP.
But while the British singer has made a huge difference, after three decades there is still much more to be done, stresses Aslett.
"I know Elton would say we've lost so much and we've come so far because of AIDS, we cannot give up now. The fight against AIDS is mobilizing the greatest support even seen for a health issue," she said.
"As we go into the fourth decade since HIV first appeared, we must work towards an end for this global killer."