May 1, 2009
The New York Times on Friday examined an HIV blood test, which seeks out bits of the virus' RNA and can identify infections during the acute or primary phase. Standard rapid tests, which detect HIV antibodies, can provide immediate results but are not likely to identify an infection that has occurred in the past month. The RNA tests, which can identify infections in one week to 10 days, are able to detect infections in the early stages, when HIV is replicating but the immune system has not mounted a response. According to the Times, although many health officials and HIV/AIDS experts see detecting newly infected HIV-positive people as an "important next step in controlling the spread of HIV," the RNA test, the "only one capable of detecting the newest infections, has not been widely adopted for this purpose."
"People with acute infection have more virus in the blood, and if they're unaware they're infected, they're more likely to engage in risky behavior," Kenneth Mayer of Brown University said. He added that finding people with new infections sooner and providing them with counseling will help prevent the spread of HIV. Some studies indicate that newly infected HIV-positive people could be the source of 10% to 50% of all new HIV transmissions, the Times reports.
Although CDC has done pilot studies of RNA testing in some cities, current national guidelines focus more on widespread antibody testing. According to the Times, RNA testing has been tried rarely in part because it is expensive, requires drawing blood and laboratory work, and does not produce immediate results. However, health departments in North Carolina and San Francisco have used the RNA tests in some settings for a few years. These health departments have reduced costs by pooling several blood samples and testing them at the same time. Officials in these areas say that they have detected dozens of cases of acute HIV infection that were not detected through the standard test, adding that wider use of the RNA test is needed.
The Times reports that a less expensive version of the RNA test might be available soon. CDC recently launched a study to compare RNA testing with an advanced version of the standard test. The new version, called an antibody-antigen test, is easy to administer and can detect substances produced by HIV in its early stages. The new test appears to be able to identify 85% of the acute infections detected by the RNA and could be commercially available next year, according to CDC officials (Tuller, New York Times, 4/30).
If "everyone were tested" for HIV, the "stigma surrounding AIDS testing might decrease," columnist Michael Gerson writes in a Washington Post opinion piece, adding, "It takes only 20 minutes." According to Gerson, he recently received an HIV test in the Ward 7 neighborhood of Washington, D.C., which has become a "new ground zero in the American AIDS crisis." He adds that the disease primarily affects district residents who are "geographically isolated, often poor and thus largely invisible." Unity Health Care, which provides health services in Ward 7, recommends "three changes to confront the epidemic," Gerson writes, adding, "First, AIDS needs to be discussed at home." Second, staff members "argue for the 'routinization' of AIDS within the range of infectious diseases," Gerson writes, adding, "Third, testing needs to be broader." According to Gerson, people who are aware of their HIV-positive status are "more likely to change their behavior and get treatment for opportunistic infections. Early treatment can also reduce the virus to a nearly undetectable level in the body." This "raises an interesting prospect supported by" NIAID Director Anthony Fauci, Gerson writes, adding that although the prospect of developing an HIV/AIDS vaccine "remains unlikely in the short term, what if we were to begin treatment with AIDS drugs as soon as someone is diagnosed with HIV instead of waiting, as we do now, until later stages? Lower viral loads would inhibit transmission." The "obstacles are immense," Gerson writes, adding, "But even the attempt would have many good effects. It would encourage early care and effective prevention" (Gerson, Washington Post, 5/1).
Reprinted with permission from kaisernetwork.org. You can view the entire Kaiser Daily HIV/AIDS Report, search the archives, or sign up for email delivery at www.kaisernetwork.org/dailyreports/hiv. The Kaiser Daily HIV/AIDS Report is published for kaisernetwork.org, a free service of the Kaiser Family Foundation, by The Advisory Board Company. © 2009 by The Advisory Board Company and Kaiser Family Foundation. All rights reserved.