Vital signs: HIV testing and diagnosis among adults--United States, 2001-2009.

BACKGROUND: Human immunodeficiency virus (HIV) infection is a major cause of morbidity, mortality, and health-care expenditures in the United States. HIV testing and linkage to care are essential to identify persons early in their course of infection to prevent progression to acquired immunodeficiency syndrome (AIDS) and death, and to reduce transmission.
METHODS: CDC used 2001-2009 data from the National Health Interview Survey to estimate percentages of persons aged 18--64 years who reported ever being tested for HIV in the United States. Data from the National HIV Surveillance System were used to estimate numbers, percentages, and rates of HIV diagnoses, AIDS diagnoses, and late diagnoses of HIV infection (defined as an AIDS diagnosis made <12 months from an initial HIV diagnosis) for persons diagnosed with HIV infection during 2001--2008 and reported to CDC through June 2009; these were used to determine populations and regions most affected by HIV and AIDS, late diagnoses, and trends in late diagnoses over time.
RESULTS: The percentage of persons aged 18-64 years ever tested for HIV was stable at approximately 40% from 2001 to 2006, increasing to 45.0% in 2009. The percentage of persons with late diagnoses of HIV infection was stable at approximately 37% from 2001 to 2004, decreasing to 32.3% by 2007 (most recent data available). In the 37 states with mature HIV reporting systems in 2007, the percentage of persons diagnosed late ranged from 25.0% to 47.2%. In 2008, most HIV diagnoses, by race/ethnicity, were among blacks or African Americans (51.2%) and, by transmission category, were among non-drug-injecting men reporting male-to-male sexual contact (55.0%). AIDS diagnosis rates were highest in the South and Northeast census regions and in the most populated states.
CONCLUSIONS: The number of persons in the United States who report ever being tested for HIV is increasing, and fewer persons are being diagnosed late in their infection. However, nearly one third of diagnoses still occur late. Increased testing efforts are needed, particularly among populations that account for most HIV diagnoses. IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: All health-care providers should expand routine HIV screening so that all adults are tested. Members of populations with higher rates of HIV diagnoses and living in geographic areas with high HIV prevalence should be screened more frequently than others. Persons likely to be at high risk for HIV infection (e.g., gay, bisexual, and other men who have sex with men) should be tested at least annually. Public health officials should emphasize the importance of HIV testing and allocate resources to increase testing among populations with the highest rates of HIV diagnoses.