Historically, laboratory tests were conducted to identify recent infections [1, 2, 3]. Antibody-based tests for recent infection (TRI) can distinguish recent from long-term HIV infection [4, 5]. Their interpretation is challenged by factors that can cause ‘false-recent’ results such as :
- Variable immune responses at the individual-level,
- Variable performance of the assay across diverse HIV-1 subtypes and across populations with naturally low viral loads, or
- Current ART use and advanced HIV disease.
To improve the accuracy of interpretation, recent infection testing algorithms (RITAs) incorporate the TRI result with other markers of chronic infection (e.g., low viral load, evidence of treatment) .
Rapid tests for recent infection (RTRIs), such as the Asante HIV-1 Rapid Recency Assay, combine verification of HIV diagnosis and differentiation between recent and long-term HIV-1 infection in one testing device [8, 9, 10]. The test can be completed in 20 minutes, making it a fast way to test individuals. An advantage of the RTRI in comparison to a conventional laboratory-based TRI is that it can be applied in routine HIV testing services (HTS) and the results can be returned to the tested client with appropriate counseling during the visit.
Evaluations of the RTRI provide preliminary data on diagnostic accuracy of the test and mean duration of recent infection detected by the test, which is approximately six months. RTRI tests pave the way for a HIV recent infection surveillance system as part of routine HTS to detect and characterize recent HIV infection among newly diagnosed HIV cases.
- Murphy G, Parry JV. Assays for the detection of recent infections with human immunodeficiency virus type 1. Eurosurveillance, 2008, 13:pii=18966.
- Le Vu S et al. Performance of an immunoassay at detecting recent infection among reported HIV diagnoses. AIDS, 2009, 24:1773–1779.
- Parekh BS et al. Quantitative detection of increasing HIV type 1 antibodies after seroconversion: a simple assay for detecting recent HIV infection and estimating incidence. AIDS Research and Human Retroviruses, 2002, 18:295–307.
- Wei X et al. Development of two avidity-based assays to detect recent HIV type 1 seroconversion using a multisubtype gp41 recombinant protein. AIDS Research and Human Retroviruses, 2010, 26:61–71.
- Barin F et al. Development and validation of an immunoassay for identification of recent human immunodeficiency virus type 1 infections and its use on dried serum spots. Journal of Clinical Microbiology, 2005, 43:4441–4447.
- Centers for Disease Control and Prevention (CDC). Consultation on Advancing HIV Incidence Surveillance Summary. https://www.cdc.gov/hiv/pdf/statistics_cahivis.pdf. Accessed February 8, 2019.
- World Health Organization (WHO). UNAIDS/WHO Working Group on Global HIV/AIDS and STI Surveillance: When and how to use assays for recent infection to estimate HIV incidence at a population level, 2011.
- Soroka SD et al. Modification of rapid human immunodeficiency virus (HIV) antibody assay protocols for detecting recent HIV seroconversion. Clinical and Diagnostic Laboratory Immunology, 2005, 12:918–921.
- UNAIDS, Global HIV Strategic Information Working Group. Recent infection testing algorithm technical update: Applications for HIV surveillance and programme monitoring, 2018.
- World Health Organization (WHO). WHO Working Group on HIV Incidence Measurement and Data Use: Meeting Report, 2018.