title: Screening Yield of HIV Antigen/Antibody Combination and Pooled HIV RNA Testing for Acute HIV Infection in a High-Prevalence Population.
abstract: OBJECTIVE
  Although acute HIV infection contributes disproportionately to onward HIV transmission, HIV testing has not routinely included screening for acute HIV infection.
  
  
  OBJECTIVE
  To evaluate the performance of an HIV antigen/antibody (Ag/Ab) combination assay to detect acute HIV infection compared with pooled HIV RNA testing.
  
  
  METHODS
  Multisite, prospective, within-individual comparison study conducted between September 2011 and October 2013 in 7 sexually transmitted infection clinics and 5 community-based programs in New York, California, and North Carolina. Participants were 12 years or older and seeking HIV testing, without known HIV infection.
  
  
  METHODS
  All participants with a negative rapid HIV test result were screened for acute HIV infection with an HIV Ag/Ab combination assay (index test) and pooled human immunodeficiency virus 1 (HIV-1) RNA testing. HIV RNA testing was the reference standard, with positive reference standard result defined as detectable HIV-1 RNA on an individual RNA test.
  
  
  METHODS
  Number and proportion with acute HIV infections detected.
  
  
  RESULTS
  Among 86,836 participants with complete test results (median age, 29 years; 75.0% men; 51.8% men who have sex with men), established HIV infection was diagnosed in 1158 participants (1.33%) and acute HIV infection was diagnosed in 168 participants (0.19%). Acute HIV infection was detected in 134 participants with HIV Ag/Ab combination testing (0.15% [95% CI, 0.13%-0.18%]; sensitivity, 79.8% [95% CI, 72.9%-85.6%]; specificity, 99.9% [95% CI, 99.9%-99.9%]; positive predictive value, 59.0% [95% CI, 52.3%-65.5%]) and in 164 participants with pooled HIV RNA testing (0.19% [95% CI, 0.16%-0.22%]; sensitivity, 97.6% [95% CI, 94.0%-99.4%]; specificity, 100% [95% CI, 100%-100%]; positive predictive value, 96.5% [95% CI, 92.5%-98.7%]; sensitivity comparison, P < .001). Overall HIV Ag/Ab combination testing detected 82% of acute HIV infections detectable by pooled HIV RNA testing. Compared with rapid HIV testing alone, HIV Ag/Ab combination testing increased the relative HIV diagnostic yield (both established and acute HIV infections) by 10.4% (95% CI, 8.8%-12.2%) and pooled HIV RNA testing increased the relative HIV diagnostic yield by 12.4% (95% CI, 10.7%-14.3%).
  
  
  CONCLUSIONS
  In a high-prevalence population, HIV screening using an HIV Ag/Ab combination assay following a negative rapid test detected 82% of acute HIV infections detectable by pooled HIV RNA testing, with a positive predictive value of 59%. Further research is needed to evaluate this strategy in lower-prevalence populations and in persons using preexposure prophylaxis for HIV prevention.
authors.affiliation: Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Peters
authors.affiliation: New York City Department of Health and Mental Hygiene, New York City.
authors.forename: Emily
authors.initials: E
authors.lastname: Westheimer
authors.affiliation: San Francisco Department of Public Health, San Francisco, California.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Cohen
authors.affiliation: University of North Carolina at Chapel Hill, Chapel Hill.
authors.forename: Lisa B
authors.initials: LB
authors.lastname: Hightow-Weidman
authors.affiliation: San Francisco Department of Public Health, San Francisco, California5Alameda County Department of Public Health, Oakland, California.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Moss
authors.affiliation: New York City Department of Health and Mental Hygiene, New York City.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Tsoi
authors.affiliation: ICF International, Atlanta, Georgia.
authors.forename: Laura
authors.initials: L
authors.lastname: Hall
authors.affiliation: San Francisco Department of Public Health, San Francisco, California.
authors.forename: Charles
authors.initials: C
authors.lastname: Fann
authors.affiliation: New York City Department of Health and Mental Hygiene, New York City7Mount Sinai School of Medicine, New York City, New York.
authors.forename: Demetre C
authors.initials: DC
authors.lastname: Daskalakis
authors.affiliation: University of North Carolina at Chapel Hill, Chapel Hill.
authors.forename: Steve
authors.initials: S
authors.lastname: Beagle
authors.affiliation: Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Pragna
authors.initials: P
authors.lastname: Patel
authors.affiliation: Callen Lorde Community Health Center, New York City, New York.
authors.forename: Asa
authors.initials: A
authors.lastname: Radix
authors.affiliation: North Carolina Department of Public Health, Raleigh.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Foust
authors.affiliation: San Francisco Department of Public Health, San Francisco, California.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Kohn
authors.affiliation: University of North Carolina at Chapel Hill, Chapel Hill.
authors.forename: Jenni
authors.initials: J
authors.lastname: Marmorino
authors.affiliation: San Francisco Department of Public Health, San Francisco, California5Alameda County Department of Public Health, Oakland, California.
authors.forename: Mark
authors.initials: M
authors.lastname: Pandori
authors.affiliation: New York City Department of Health and Mental Hygiene, New York City.
authors.forename: Jie
authors.initials: J
authors.lastname: Fu
authors.affiliation: Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Taraz
authors.initials: T
authors.lastname: Samandari
authors.affiliation: University of North Carolina at Chapel Hill, Chapel Hill.
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Gay
mesh_terms: D000208:Acute Disease; D000328:Adult; D002140:California / Q000453:epidemiology; D005260:Female; D015483:HIV Antibodies / Q000032:analysis*; D015488:HIV Antigens / Q000032:analysis*; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000235:genetics*; D018451:Homosexuality, Male / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009518:New York; D009657:North Carolina / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012367:RNA, Viral / Q000032:analysis*; D012680:Sensitivity and Specificity
chemical_list: D015483:HIV Antibodies; D015488:HIV Antigens; D012367:RNA, Viral