Short Communication: Low False Recent Rate of Limiting Antigen-Avidity Assay Combined with HIV-1 RNA Data in Botswana

AIDS Res Hum Retroviruses. 2017 Jan;33(1):17-18. doi: 10.1089/AID.2016.0127. Epub 2016 Sep 7.


Cross-sectional estimation of HIV incidence could misclassify some established or chronic HIV infections as recent. Usually long-term nonprogressors, elite and viremic controllers, and individuals on ART contribute to misclassification. Local data on the false recent rate (FRR) could minimize misclassification during estimation of HIV incidence. To improve monitoring of HIV incidence, we estimated local FRR in Botswana. A total of 1,036 specimens from individuals infected for at least 1.5-2 years were sampled between 2004 and 2009 and tested using the limiting antigen (LAg)-avidity assay using a cutoff of 1.5 normalized optical density units. The FRR was 0.97% (10/1,036; 95% confidence interval [CI] 0.46-1.77). Four samples had HIV-1 RNA >1,000 cps/ml, giving an adjusted FRR of 0.39% (4/1,036; 95% CI 0.11-0.99). A combination of LAg and HIV-1 RNA load data resulted in FRR below 1% in the Botswana population.

Keywords: HIV incidence; HIV recency; cross-sectional incidence; false recency rate; limiting antigen assay.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibody Affinity*
  • Botswana / epidemiology
  • Diagnostic Errors*
  • Female
  • HIV Antigens / immunology*
  • HIV Infections / diagnosis*
  • HIV Infections / epidemiology
  • HIV Infections / immunology
  • HIV Infections / virology
  • Humans
  • Immunoassay / methods*
  • Incidence
  • Male
  • Molecular Diagnostic Techniques / methods*
  • RNA, Viral / blood*


  • HIV Antigens
  • RNA, Viral