More than 80 million adults between the ages of 18 and 64 were tested for HIV in 2009, a record high according to a Centers for Disease Control and Prevention (CDC) statement. In fact, it's an increase of more than 11 million since 2006, when the CDC recommended HIV testing become a part of routine care for adults and adolescents. The CDC estimates that more than 1.1 million adults are living with the virus in the United States—and one in five of them (about 200,000) doesn't know it. A critical part of fighting the HIV epidemic is reducing the number of undiagnosed cases, since HIV is mostly transmitted by people who don't know their status. The Obama administration's National HIV/AIDS Strategy has pledged to increase the percentage of HIV-positive people who know their status to 90 percent.

To read the CDC statement, click here.