There is some good news about the pandemic this World AIDS Day. Fewer people are becoming infected with HIV than at the peak of the epidemic, according to Unaids. But we can't be complacent: 2.6 million people became newly infected in 2009, and the epidemic still rages with a vengeance in southern Africa.
Yet a revolution in HIV prevention may be at hand, and it might just be found in a pill, a microbicide gel, and — perhaps most importantly — the personal courage of Pope Benedict XVI.
The pill is Truvada, which combines two antiretroviral drugs usually given to people already infected with HIV. It prevents the virus from replicating, and it is already available by prescription in many countries. A well-designed study published last week in the New England Journal of Medicine found that 44 percent of people who took the drug as prophylactic were less likely to get infected than an equal number taking a placebo. (The study looked at 2,500 gay men from the United States and five other countries.)