At least six testing sites in San Francisco, New York City and Los Angeles earlier this month discontinued use of OraSure Technologies' oral OraQuick Advance Rapid HIV 1/2 Antibody Test, as CDC and FDA investigate reports of an abnormal number of false positive results from the tests, the Los Angeles Times reports (Lin/Chung, Los Angeles Times, 12/20). The test requires users to swab their gums and then place the swab in a holder. After 20 minutes, one line appears on the strip if the HIV result is negative, and two appear if the result is positive (Kaiser Daily HIV/AIDS Report, 12/16). The San Francisco Department of Public Health announced that of 9,400 tests conducted at 14 public health clinics in the city in 2005, 49 HIV-positive results from OraQuick oral tests later were determined to be false positives. In addition, New York City Assistant Health Commissioner Susan Blank said the city recorded 30 false-positive results in November after recording an average of about five false-positive results in previous months (Kaiser Daily HIV/AIDS Report, 12/12). The New York City Department of Health and Mental Hygiene, the L.A. Gay and Lesbian Center, the University of California-San Francisco AIDS Health Project and three smaller testing centers in San Francisco have stopped offering the oral test to patients because of concerns about false positive results, according to the Times. The testing sites now use the OraQuick blood test (Los Angeles Times, 12/20). The rapid blood test, which uses blood collected from a "finger stick," has not had comparable issues with false positives (Kaiser Daily HIV/AIDS Report, 12/16). However, other prominent testing sites -- including the AIDS Healthcare Foundation in Los Angeles, Gay Men's Health Crisis Center in New York and Whitman-Walker Clinic in Washington, D.C. -- have not reported abnormal increases in false positives. FDA and CDC officials said they are investigating complaints of false positives but, to date, have not found data that warrant pulling the test off the market. "Some false positive results are expected with any HIV" test, FDA spokesperson Kimberly Rawlings said, adding that "additional testing is always needed to confirm true positive results" (Los Angeles Times, 12/20).