NEW YORK — The rate of HIV infections diagnosed in the United States each year fell by one-third over the past decade, a government study finds. Experts celebrated it as hopeful news that the AIDS epidemic may be slowing in the United States.
The reasons for the drop aren't clear. It might mean fewer new infections are occurring. Or that most infected people already have been diagnosed, so more testing won't necessarily find many more cases.
"It could be we are approaching something of a 'ceiling effect,' " said one study leader, David Holtgrave of Johns Hopkins University.
The study found that 16 out of every 100,000 people ages 13 and older were newly diagnosed with HIV in 2011, a steady decline from 24 out of 100,000 people in 2002.
The study was released online Saturday by the Journal of the American Medical Association. It is part of the journal's special report on HIV research, issued ahead of the International AIDS Conference that starts today in Melbourne, Australia.
HIV is the virus that causes AIDS, which destroys the immune system. The World Health Organization estimates 35 million people globally have the virus. In the United States, 1.1 million people are thought to be infected, though many don't know it.