The United Nations estimates that about 34 million people are living with the human immunodeficiency virus (HIV) that causes AIDS. In a report released ahead of the International AIDS Society's 2012 annual meeting set for next week in Washington, D.C., it said that the number of worldwide AIDS-related deaths fell to 1.7 million last year from some 1.8 million in 2010. AIDS deaths peaked at 2.3 million in 2005.

The decline has been fueled by greater access to medications that help more people live with the disease. An estimated 8 million people in lower-income countries are receiving antiretroviral drugs, and the United Nations has set a target to raise that to 15 million by 2015.

Funding for HIV prevention and treatment totaled $16.8 billion last year. Of that amount, $8.2 billion came from international sources including the United States, which donated 48 percent of it. The amount of money spent by poor and middle-income countries reached $8.6 billion last year, surpassing international investment for the first time. The U.N. estimates that another $5 billion is needed to reach its 2015 goals.

The U.N. is also talking with pharmaceutical companies about how to improve access to lower-cost versions of simpler HIV treatments that combine several drugs in a single pill.

"We need innovation which will reduce the cost of medicine," Michel Sidibe, executive director of UNAIDS, said during a telephone interview. "If we want to maintain people on second- and third-line medicine it will not be possible with the price of the drugs we have today."

Paul De Lay, UNAIDS deputy executive director, speaking a briefing in Geneva, said overall progress in treating the disease could be jeopardized by a surge in infection seen in smaller patient groups, including in Eastern Europe and the United States.

"We are looking at an epidemic that's going to last another 40 to 50 years to get down to what we would consider the lowest possible number of infections," De Lay said.

"It reminds us that prevention must be sustained, just the way we talk about sustaining treatment. Until we have a vaccine this is still going to have to be part of all countries' health programs," he said.

LOOKING FOR MORE OPTIONS

Public health officials are considering wider use of HIV medications in people who are not infected with the virus but have a high risk of contracting it. Earlier this week, U.S. health regulators for the first time approved use of Gilead Sciences Inc's Truvada drug for preventing HIV.

Such antiretroviral drugs, also sold by companies like GlaxoSmithKline and Merck & Co, are designed to keep the virus that causes AIDS in check by suppressing viral replication in the blood.

Researchers are also working on using HIV-fighting antibodies to prevent infection, and they say their efforts could yield a licensed vaccine.

In the meantime, treating more people infected with HIV remains a priority. UNAIDS estimated that in sub-Saharan Africa, a region encompassing countries like Kenya, Nigeria and South Africa, 31 percent fewer people died from AIDS-related causes in 2011 compared with 2005.

The region "has actually been able to scale up more than other parts of the world, more than Eastern Europe and Central Asia, more than North Africa and the Middle East, and even more than Asia, with a 62 percent coverage rate of people eligible for treatment able to access treatment," said Dr. Gottfried Hirnschall, director of the HIV Department at the World Health Organization.

Access to therapy also led to lower rates of AIDS-related deaths in Latin America, the Caribbean and Oceania.

In Western and Central Europe, as well as North America, where antiretroviral therapy is extensively available, the combined number of AIDS-related deaths has varied little over the past decade, totaling about 29,000 last year, according to the United Nations.

Death rates were also stable in Asia at an estimated 330,000, while AIDS-related deaths continued to rise in Eastern Europe, Central Asia, the Middle East and North Africa.

New infections among children declined for the second year in a row amid focused efforts to protect them and their mothers against HIV. About 330,000 children were newly infected with HIV in 2011, down from 570,000 in 2003.

(Editing by Michele Gershberg, Maureen Bavdek and M.D. Golan)

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