title: Cost-Effectiveness of Frequent HIV Testing of High-Risk Populations in the United States.
abstract: OBJECTIVE
  Data showing a high incidence of HIV infection among men who have sex with men (MSM) who had annual testing suggest that more frequent HIV testing may be warranted. Testing technology is also a consideration given the availability of sensitive testing modalities and the increased use of less-sensitive rapid, point-of-care antibody tests. We assessed the cost-effectiveness of HIV testing of MSM and injection drug users (IDUs) at 3- and 6-month intervals using fourth-generation and rapid tests.
  
  
  METHODS
  We used a published mathematical model of HIV transmission to evaluate testing intervals for each population using cohorts of 10,000 MSM and IDU. We incorporated HIV transmissions averted due to serostatus awareness and viral suppression. We included costs for HIV testing and treatment initiation, and also treatment costs saved from averted transmissions.
  
  
  RESULTS
  For MSM, HIV testing was cost saving or cost effective over a 1-year period for both 6-month compared with annual testing and quarterly compared with 6-month testing using either test. Testing IDU every 6 months compared with annually was moderately cost effective over a 1-year period with a fourth-generation test, while testing with rapid, point-of-care tests or quarterly was not cost effective. MSM results remained robust in sensitivity analysis, whereas IDU results were sensitive to changes in HIV incidence and continuum-of-care parameters. Threshold analyses on costs suggested that additional implementation costs could be incurred for more frequent testing for MSM while remaining cost effective.
  
  
  CONCLUSIONS
  HIV testing of MSM as frequently as quarterly is cost effective compared with annual testing, but testing IDU more frequently than annually is generally not cost effective.
authors.affiliation: Division of HIV/AIDS Prevention, National Center for HIV, Viral Hepatitis, STD and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA.
authors.forename: Angela B
authors.initials: AB
authors.lastname: Hutchinson
authors.forename: Paul G
authors.initials: PG
authors.lastname: Farnham
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Sansom
authors.forename: Emine
authors.initials: E
authors.lastname: Yaylali
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Mermin
mesh_terms: D015331:Cohort Studies; D003362:Cost-Benefit Analysis; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000191:economics* / Q000453:epidemiology / Q000635:transmission; D017048:Health Care Costs; D018451:Homosexuality, Male; D006801:Humans; D015994:Incidence; D008297:Male; D000067716:Point-of-Care Testing / Q000191:economics; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015819:Substance Abuse, Intravenous / Q000150:complications*; D013997:Time Factors; D014481:United States / Q000453:epidemiology