Prince Harry thinks the lack of youth education about HIV is "totally absurd".
The 32-year-old royal made the remarks during an appearance at the London School of Hygiene and Tropical Medicine, where he called for an end to the stigma surrounding the disease.
He said: "To me it is totally absurd that in today’s world that young people, the first time they know or the first time they hear anything about HIV and Aids, is probably by the time it is too late.
"HIV needs to be treated exactly the same as any other disease, and between us hopefully we can eradicate the stigma and give these young people an opportunity to stand up."
During the discussion group staged by his charity Sentebale, the British royal was introduced to three young people from Lesotho and Botswana, who discussed their experiences of living with HIV.
Tloto, an 18-year-old girl from Botswana, told the Evening Standard newspaper: "I decided to discuss my status so I can grant them courage, I can give hope to those who are hopeless."
Meanwhile, Ts’epang, 19, from Lesotho, was pleased to have been afforded the opportunity to pass on knowledge to children aged 12 to 14.
Ts’epang said: "We learned they didn’t know about HIV-related issues, but now they know with the information we gave them."
Since it was founded in 2006, Sentebale has provided adolescent-friendly HIV testing to more than 21,000 people.