Baltimore Launches HIV Nucleic Acid Testing Program

Baltimore health clinics have started to provide nucleic acid testing, which can detect HIV one to two weeks after infection, the Baltimore Sun reports (Bor, Baltimore Sun, 7/12). NAT, which was developed in 1999, is used to test units of donated blood for HIV. NAT can detect minute amounts of viral genetic material in pooled plasma samples by amplifying gene fragments of the virus. If a pool tests positive for HIV, the individual sample can be detected and removed for further processing, and the donor can be deferred and notified. Because NAT looks for the virus and not antibodies, health professionals are able to identify HIV-positive patients in the days immediately following infection -- when they are most contagious (Kaiser Daily HIV/AIDS report, 3/22). Baltimore in 2004 had the fifth highest number of new AIDS cases of any U.S. city, the Sun reports. The city performs about 22,000 HIV tests annually in public health and mobile van clinics, as well as through community agencies. According to Emily Erbelding, chief of medical services for the sexually transmitted infection department of the city's Health Department, of those who are tested, about 3%, or 660 people, test HIV-positive. With the new test, the health department should be able to diagnose 25 to 30 HIV-positive people annually who otherwise would not have tested positive, Erbelding said. The test "offers patients the opportunity to learn their HIV status earlier in the infection and gives the city the ability to understand where HIV infection is occurring now," Joshua Sharfstein, the city's health commissioner, said, adding, "That knowledge is the key to intervening and slowing down the spread of the virus." To date, the state has identified 12 new HIV cases using NAT, Robert Myers, deputy director of laboratories for the state Department of Health and Mental Hygiene, said. The testing initiative receives funding from $320,000 in general revenues approved by the City Council, the Sun reports. North Carolina in 2002 became the first state to use NAT for HIV testing. Los Angeles, Rochester, N.Y., San Francisco and Seattle have begun using NAT as well, the Sun reports (Baltimore Sun, 7/12).