At least 45% of American adults have been tested for HIV at least once, an increase of five percentage points and 11.4 million people since 2006, the Centers for Disease Control and Prevention said Tuesday. But that still leaves 55% of adults, and 28.3% of adults with risk factors for contracting HIV, who have never been tested, the agency said in a Vital Signs report. About 48% of women have been tested, but only 41% of men.
The CDC estimates that about 1.1 million Americans are HIV-positive and that about 200,000 of them do not know it because they have never been tested. More than 30% of those who do become diagnosed as HIV-positive do so only after they have been positive for several years, which makes controlling the infection much more difficult. A growing body of evidence also suggests that prolonged unrecognized infection also increases the risk of cardiovascular disease and other medical problems not directly related to AIDS. When people learn they are infected, they can also take steps to protect their sexual partners.
These facts prompted the CDC to recommend in 2006 that HIV testing become a routine part of all medical care for adults and adolescents and that people at high risk of infection, particularly gay males, but also those who abuse intravenous drugs, be tested once a year. All pregnant women should also be tested to protect their infants. Before 2006, the percentage of Americans who had ever been tested had plateaued at 40% between 2001 and 2006.