"There is a normal human tendency to look for the magic bullet, but my friends, it doesn't exist," Piot said in one of his last speeches before he steps down as the head of UNAIDS.
"Can we now just agree for all that we have to come to terms with complexity and rather than to have this absurd search for the magic bullet?"
"Even the day we have a vaccine - and I hope we will have it - we will still need many things," he added.
Sub-Saharan Africa is home to two-thirds of the global total of 32.9 million people with the HIV virus. Piot called it "a perfect storm of small differences" that made Africa the continent where AIDS is the number one cause of death, according to the World Health Organisation.
"The agenda for the immediate future is clear: we need more of the same" being access to treatment and access to prevention, Piot stressed.
He acknowledged the difficulties in getting funding with the current financial crisis but insisted more funding was needed to fight AIDS in Africa.
"The need and the capacity to use the money will continue to grow in Africa over the years for a while and it will continue to grow until we are highly successful with HIV prevention," he warned in his overview of 25 years of AIDS in Africa.
The 15th International Conference on AIDS and Sexually Transmitted Infections in Africa (ICASA) runs until Sunday.