On the second day of a major international AIDS conference in Amsterdam, the two lent their mega-wattage star power to calls for action to end the lingering stigma around the virus and protect generations to come.
"Young people are the only age group where HIV infections are rising, not falling," warned rock star and veteran AIDS campaigner Elton John as he announced the launch of the MenStar Coalition.
"We have to do much, much more to bring men, especially younger men more fully into the fold," he insisted.
The coalition brings together different partners, including the UN's Unitaid and the US fund PEPFAR, as John warned that 24- to 35-year-old men were accessing HIV testing and treatment at "unacceptably low rates".
Much work has been done to protect women and girls but "we can't solve the whole problem if we are only addressing half the situation," John said.
"If we want to win this fight, if we want to end AIDS once and for all, we must make men part of the solution" and teach them to protect themselves, "not only their wives and girlfriends, their sisters, and daughters, but also critically their brothers and their sons."
- 'Dangerous complacency' -
Some 15,000 delegates -- researchers, campaigners, activists and people living with the HIV virus which causes AIDS -- have gathered for the five-day war council, amid dire warnings the AIDS epidemic could yet spiral out of control.
"The progress we have fought so hard for is at risk from a dangerous complacency," Prince Harry told conference delegates.
"Too many around the world are still ignoring the damaging knock-on effects on education and other community services for not prioritising HIV prevention and treatment."
The new initiative was focused on "the tough but essential work of truly changing mindsets," the Duke of Sussex said.
"Inspired by the growing alarm of the rate of new HIV infections among young women, this campaign is bravely tackling the root of this problem -- the lack of awareness of HIV prevention amongst hard-to-reach young men."
He urged people to unite around the "smashing of a deadly stigma" surrounding HIV, "and calling out the prejudice that is still there".
South African actress Charlize Theron agreed as she addressed the day's opening plenary session entitled: "Breaking the barriers of inequity".
"We have come a long way as a global community from that moral panic that defined early stages of this epidemic," she told the audience.
But she warned that "most of us now know and understand that HIV is not just about sex or sexuality... We know it is linked to the second-class status of women and girls worldwide."//AFP