While the new single sounds like something Lennox would have made with the rock group the Eurythmics, the singer told The Sunday Times of London there is a deeper meaning behind "Sing."

"For years, I've been wondering how I can maximize what I do to tell people about HIV in Africa," Lennox said. "With 'Sing,' I'm encouraging women at risk to find out about their status because there's such a stigma about talking about AIDS in the places where it's most rife."

Among the celebrity singers who accepted Lennox's invitation to record "Sing" were Madonna, Shakira and Celine Dion.

The Times said "Sing," which Lennox performed at last December's World AIDS Day Concert in South Africa, will be available online Monday and will be in retail stores March 17.