The nonprofit International Antiviral Society-USA cited new evidence that untreated infection with the human immunodeficiency virus that causes AIDS can also lead to a range of other conditions, including cardiovascular disease and kidney disease. In addition, data have shown that suppressing HIV reduces the risk of an infected person passing the virus to another person.

"We are no longer only focused on traditional AIDS-defining infections. We know that HIV is doing damage to the body all the time when it is not controlled," said Dr. Melanie Thompson, principal investigator of the AIDS Research Consortium of Atlanta and a member of the Antiviral Society panel.

The recommendations are global, but mainly aimed at "resource-rich" countries who can cover the cost of the medications, she said. The guidelines were published in the Journal of the American Medical Association at the start of the International AIDS Society's 2012 conference, which runs from Sunday through Friday in Washington, DC.

In addition to studies showing that treatment with antiretroviral drugs reduces the risk of HIV transmission, trials have shown a protective effect when the drugs are used by at-risk people who are not already infected with the virus.

U.S. health regulators earlier this month approved use of Gilead Sciences' Truvada for HIV-negative adults who are at risk of acquiring the virus. Like other antiretroviral drugs, the Gilead pill is designed to keep the virus that causes AIDS in check by suppressing viral replication in the blood.

"The drugs are convenient, have very little side effects and their benefits are becoming clearer and clearer -- both for the infected person and from a public health standpoint," said Dr. Paul Volberding, director of the Center for AIDS Research at the University of California, San Francisco and another member of the panel.

CHECKING WHITE BLOOD CELL LEVELS

The guidelines echo those issued in March by the U.S. Department of Health and Human Services, which also cited improved drugs and new studies showing patients benefit from treatment regardless of their level of infection-fighting white blood cells.

Previous recommendations called for antiretroviral drugs to be started for only patients whose CD4 cell counts had fallen below 500 per cubic millimeter of blood.

A normal CD4 count in a healthy adult varies between 500 and 1,200, according to HHS.

Earlier guidelines were based largely on the potential for health complications associated with initial antiretrovirals as well as concerns that patients without symptoms might not adhere to the therapy.

"The risk/benefit of the kinds of therapies we had available led us to be more restrictive in terms of when to start treatment," Dr. Thompson said.

The availability of new multidrug combination pills has made it easier for patients to take them consistently and has lessened the risk of drug resistance, she said.

"We were really focusing on the treatment aspect of it and didn't have the prevention data, which we now have," Dr. Volberding said.

The United Nations estimates that around 34 million people are living with HIV, including more than 1.2 million Americans.

The World Health Organization recommends that people diagnosed with HIV start taking antiretroviral therapy when their CD4 cell count hits 350 or less. It said this week that it is reviewing recent studies pointing to the potential benefits of giving the drugs earlier, before the immune system starts to weaken.

(Reporting By Deena Beasley; Editing by Michele Gershberg and M.D. Golan)

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