title: Epidemiology of HIV in the United States.
abstract: BACKGROUND
  The United States has a comprehensive system of HIV surveillance, including case reporting and disease staging, estimates of incidence, behavioral, and clinical indicators and monitoring of HIV-related mortality. These data are used to monitor the epidemic and to better design, implement, and evaluate public health programs.
  
  
  METHODS
  We describe HIV-related surveillance systems and review recent data.
  
  
  RESULTS
  There are more than 1.1 million people living with HIV in the United States, and approximately 56,000 new HIV infections annually. Risk behavior data show that 47% of men who have sex with men engaged in unprotected anal intercourse in the past year, and 33% of injection drug users had shared syringes. One third (32%) of people diagnosed with HIV in 2008 were diagnosed with AIDS within 12 months, indicating missed opportunities for care and prevention. An estimated 72% of HIV-diagnosed persons received HIV medical care within 4 months of initial diagnosis.
  
  
  CONCLUSIONS
  Conducting accurate and comprehensive HIV surveillance is critical for measuring progress toward the goals of the 2010 National HIV/AIDS Strategy: reduced HIV incidence, increased access to care, and improvements in health equity.
authors.affiliation: Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. alansky@cdc.gov
authors.forename: Amy
authors.initials: A
authors.lastname: Lansky
authors.forename: John T
authors.initials: JT
authors.lastname: Brooks
authors.forename: Elizabeth
authors.initials: E
authors.lastname: DiNenno
authors.forename: James
authors.initials: J
authors.lastname: Heffelfinger
authors.forename: H Irene
authors.initials: HI
authors.lastname: Hall
authors.forename: Jonathan
authors.initials: J
authors.lastname: Mermin
mesh_terms: D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D018451:Homosexuality, Male; D006801:Humans; D015994:Incidence; D008297:Male; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D012725:Sexual Behavior; D012919:Social Behavior; D015819:Substance Abuse, Intravenous / Q000150:complications; D013997:Time Factors; D014481:United States / Q000453:epidemiology