title: Assessment of Oral Fluid HIV Test Performance in an HIV Pre-Exposure Prophylaxis Trial in Bangkok, Thailand.
abstract: BACKGROUND
  Rapid easy-to-use HIV tests offer opportunities to increase HIV testing among populations at risk of infection. We used the OraQuick Rapid HIV-1/2 antibody test (OraQuick) in the Bangkok Tenofovir Study, an HIV pre-exposure prophylaxis trial among people who inject drugs.
  
  
  METHODS
  The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial. We tested participants' oral fluid for HIV using OraQuick monthly and blood using a nucleic-acid amplification test (NAAT) every 3 months. We used Kaplan-Meier methods to estimate the duration from a positive HIV NAAT until the mid-point between the last non-reactive and first reactive oral fluid test and proportional hazards to examine factors associated with the time until the test was reactive.
  
  
  RESULTS
  We screened 3678 people for HIV using OraQuick. Among 447 with reactive results, 436 (97.5%) were confirmed HIV-infected, 10 (2.2%) HIV-uninfected, and one (0.2%) had indeterminate results. Two participants with non-reactive OraQuick results were, in fact, HIV-infected at screening yielding 99.5% sensitivity, 99.7% specificity, a 97.8% positive predictive value, and a 99.9% negative predictive value. Participants receiving tenofovir took longer to develop a reactive OraQuick (191.8 days) than participants receiving placebo (16.8 days) (p = 0.02) and participants infected with HIV CRF01_AE developed a reactive OraQuick earlier than participants infected with other subtypes (p = 0.04).
  
  
  CONCLUSIONS
  The oral fluid HIV test performed well at screening, suggesting it can be used when rapid results and non-invasive tools are preferred. However, participants receiving tenofovir took longer to develop a reactive oral fluid test result than those receiving placebo. Thus, among people using pre-exposure prophylaxis, a blood-based HIV test may be an appropriate choice.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT00119106.
authors.affiliation: Bangkok Tenofovir Study Group, Bangkok, Thailand.
authors.forename: Pravan
authors.initials: P
authors.lastname: Suntharasamai
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.|Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Michael
authors.initials: M
authors.lastname: Martin
authors.affiliation: Bangkok Tenofovir Study Group, Bangkok, Thailand.
authors.forename: Kachit
authors.initials: K
authors.lastname: Choopanya
authors.affiliation: Bangkok Tenofovir Study Group, Bangkok, Thailand.
authors.forename: Suphak
authors.initials: S
authors.lastname: Vanichseni
authors.affiliation: Bangkok Tenofovir Study Group, Bangkok, Thailand.
authors.forename: Udomsak
authors.initials: U
authors.lastname: Sangkum
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.
authors.forename: Pairote
authors.initials: P
authors.lastname: Tararut
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.
authors.forename: Wanna
authors.initials: W
authors.lastname: Leelawiwat
authors.affiliation: Bangkok Metropolitan Administration, Bangkok, Thailand.
authors.forename: Rapeepan
authors.initials: R
authors.lastname: Anekvorapong
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Mock
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.
authors.forename: Thitima
authors.initials: T
authors.lastname: Cherdtrakulkiat
authors.affiliation: Bangkok Metropolitan Administration, Bangkok, Thailand.
authors.forename: Manoj
authors.initials: M
authors.lastname: Leethochawalit
authors.affiliation: Bangkok Metropolitan Administration, Bangkok, Thailand.
authors.forename: Sithisat
authors.initials: S
authors.lastname: Chiamwongpaet
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Roman J
authors.initials: RJ
authors.lastname: Gvetadze
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Janet M
authors.initials: JM
authors.lastname: McNicholl
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Lynn A
authors.initials: LA
authors.lastname: Paxton
authors.affiliation: Thailand Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Somyot
authors.initials: S
authors.lastname: Kittimunkong
authors.affiliation: Thailand MOPH - U.S. CDC Collaboration, Nonthaburi, Thailand.|Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Marcel E
authors.initials: ME
authors.lastname: Curlin
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D005260:Female; D015483:HIV Antibodies / Q000097:blood / Q000276:immunology; D015658:HIV Infections / Q000175:diagnosis* / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D015498:HIV-2 / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods* / Q000592:standards*; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D065129:Pre-Exposure Prophylaxis; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000068698:Tenofovir / Q000627:therapeutic use; D013785:Thailand; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents; D015483:HIV Antibodies; D011933:Reagent Kits, Diagnostic; D000068698:Tenofovir