One in five U.S. adult infected with HIV do not know it.
Nearly one in five U.S. adults infected with HIV does not know it. Reuters//Yannis Behrakis

CHICAGO (Reuters) - Only 28 percent of the 1.2 million Americans living with HIV have the infection under control, increasing the risk that they will spread the disease to others, U.S. health officials said on Tuesday.

A big part of the problem is that one in five U.S. adult infected with HIV do not know it. Of those who are aware, only half receive ongoing medical care and treatment, the U.S. Centers for Disease Control and Prevention said in its latest report on HIV in America.

It's now very clear that we have the tools to stop HIV in an individual and to stop the spread of HIV in a community, CDC Director Dr. Thomas Frieden said in a telephone interview.

We also know that taking treatment for HIV can prevent people from progressing to AIDS and from developing many of the serious complications of HIV, which unfortunately does remain an incurable infection, Frieden said.

Recent studies have shown that suppressing the virus through treatment reduces the spread of HIV to partners by as much as 96 percent.

CDC's report, released ahead of World AIDS day on December 1, focuses on increasing rates of HIV testing and treatment.

It follows new global AIDS priorities set by U.S. Secretary of State Hillary Clinton focused on HIV-fighting drugs as a way of preventing new infections that could bring the goal of an AIDS-free generation within reach.

The global plan also seeks to reduce mother-to-child transmission of HIV and expand voluntary male circumcision.

In this country, we already do a very good job with maternal-child transmission prevention, Frieden told Reuters.

He said the major area of need in the United States is in strengthening the cascade of care by improving access and making sure people continue taking their medication to ensure the virus in their body is kept low enough to prevent the spread of the infection.

The fact that nearly three quarters of Americans living with HIV still have the virus circulating in their bodies, damaging their brains and immune systems and putting their sexual partner at risk is something we think we can do a lot about, he said.

TESTING CAMPAIGN

To reach groups at the greatest risk, the CDC is launching a new campaign urging regular testing for young black gay and bisexual men, a population in which both HIV and syphilis infections continue to rise.

Frieden said studies have shown that black gay and bisexual do not engage in riskier behaviors than other gay men.

It's just that the infection has gotten into this community and therefore it's particularly important that people in the community get tested and treated, he said.

The campaign includes advertising in gay and black neighborhoods in six cities where infections in this population are highest: Atlanta, Baltimore, Houston, New York City, Oakland, California and Washington, D.C.

While the number of Americans newly infected with HIV remained stable between 2006 and 2009, infections rose nearly 50 percent among young black gay and bisexual men, according to a CDC report released in August.

Men who have sex with young men -- which includes openly gay and bisexual men and those who do not identify themselves as gay or bisexual -- remain most heavily affected.

While this group represents 2 percent of the overall U.S. population, they accounted for 61 percent of all new HIV infections in 2009.