LOS ANGELES, Aug. 7 (Xinhua) -- About one million to 1.1 million Americans are thought to be living with HIV, with the annual infecting rate reaching 56,300, according to a government report released on Thursday.

    Among those infected, 250,000 don't know it, the U.S. Centers for Disease Control and Prevention (CDC) said in the report.

    Just over 40 percent of the adult U.S. population, or about 10 percent has been screened at least once for HIV, said the report.

    The figure has remained stable since 2000 despite efforts to increase testing.

    In September 2006, the CDC recommended that all Americans be offered HIV testing as part of their routine medical care.

    Last year, the agency allocated additional funds to 23 jurisdictions to test an extra 20 million people, primarily African Americans, in hopes of identifying 20,000 more HIV-positive people.

    The goal of the increased testing is to identify infections at an earlier stage so people can begin receiving anti-AIDS drugs while the treatment can do more good. Late diagnosis increases the likelihood that the infection will proceed to more serious illness.

    In 2005, 38 percent of those newly diagnosed with HIV infections progressed to AIDS within a year, the report says.

    In addition, an HIV-positive individual who is unaware of the infection is three times as likely to transmit the virus as one who knows his or her status, CDC officials said.

    The CDC released the report to coincide with the International AIDS Conference being held this week in Mexico City.