FAQ Category: General

Can clinical history be used to improve recency classification?

Yes. In addition to VL testing as a part of RITA, recency classification can also be improved by using clinical history to identify and exclude from TRI testing persons presenting to HTS with advanced HIV disease, low CD4+ T cell count, prior HIV diagnosis and prior/long-term ARV use. However, HIV diagnosis and subsequent ARV initiation with…
Read more

How should an RTRI result with a faint long-term line be interpreted?

Any visible line, even if weak, should be interpreted as present. The long-term line measures the evolving antibody avidity and a person could truly be at the transition point between recent and long-term infection. In this case, the test may show a faint long-term line which may be detected differently by different testers.

What should be done for persons who have an HIV diagnosis and an RTRI result with only the control line (i.e., RTRI inconclusive or negative)?

Although this may happen, it should be rare. In countries where regulation or policy permits, programs may consider repeating the national algorithm to confirm HIV-positive status (if retesting for verification was not done). In general, RTRI should be repeated and the results recorded. Irrespective of RTRI results, the national HIV testing algorithm is always the…
Read more

Can the RTRI be conducted using dried blood spot (DBS)?

No. Unlike LAg-Avidity EIA, RTRI should not be performed using DBS. The RTRI should be performed using whole blood, plasma or serum specimens.

Does the RTRI detect acute HIV infection?

No. The RTRI does not detect acute HIV infection. Persons who have acute HIV infection do not have HIV antibodies and will test HIV-negative by a national HIV testing algorithm that uses HIV antibody tests. Thus, in countries where the national HIV testing algorithm is based on antibody detections, persons with acute infection will not…
Read more

Does the RTRI work among persons with HIV-2?

No. The RTRI was developed for the detection of recent HIV-1 infection. The long-term line of the test includes only HIV-1 specific antigen. Therefore, the RTRI cannot be used to detect recent infections among persons diagnosed with HIV-2. If used in geographical areas where HIV-2 is prevalent (or if HIV-2 infection is suspected), it is…
Read more

What is a Recent Infection Testing Algorithm (RITA)?

A RITA is a combination of laboratory tests used to classify an HIV infection as recent or long-term. A RITA helps A RITA is a combination of laboratory tests used to classify an HIV infection as recent or long- term. A RITA helps to reduce false recent classification when individuals are on ART and virally…
Read more

How does the RTRI compare to the HIV-1 LAg-Avidity EIA?

Both RTRI and LAg-Avidity EIA use the same gp41 multi-subtype protein and are based on the same principle of using limiting antigen to distinguish recent from long-term infections. However, the LAg-EIA is a laboratory-based assay requiring specialized equipment, while RTRI is a rapid test in lateral flow format and can be performed at HIV testing…
Read more

Who makes RTRI tests?

Currently RTRI technology has been commercialized by two manufacturers as 1) Asante HIV-1 Rapid Recency Assay (Sedia Biosciences, Portland, OR, USA) and 2) Maxim Swift Recent Infection Assay (Maxim Biomedical Incorporated, Rockville, MD, USA). Asante is available as 100 tests or 20 tests per kit, while Maxim Swift RIA is available as 20 tests per…
Read more

Who can perform the RTRI?

RTRIs should be performed by well-trained and certified staff and can be conducted at HIV testing location, in a health facility, or in a laboratory as an additional test for surveillance among persons who are newly diagnosed with HIV using the national diagnostic testing algorithm.