HIV Testing Updates and Challenges: When Regulatory Caution and Public Health Imperatives Collide

Abstract

Numerous improvements in HIV testing technology led recently to the first revision of recommendations for diagnostic laboratory testing in the USA in 25 years. Developments in HIV testing continue to produce tests that identify HIV infection earlier with faster turnaround times for test results. These play an important role in identifying HIV infection during the highly infectious acute phase, which has implication for both patient management and public health interventions to control the spread of HIV. Access to these developments, however, is often delayed by the regulatory apparatus for approval and oversight of HIV testing in the USA. This article summarizes recent developments in HIV diagnostic testing technology, outlines their implications for clinical management and public health, describes current systems of regulatory oversight for HIV testing in the USA, and proposes alternatives that could expedite access to improved tests as they become available.

Selecting an HIV Test: A Narrative Review for Clinicians and Researchers

“…Because the virological and serological events following HIV infection determine when various targets become detectable, 3,4 understanding this timeline is essential for understanding the limitations of different tests across clinical and research settings.…”

“…Since the US Food and Drug Administration (FDA) approved the first HIV diagnostic test in 1985, four additional “generations” of antibody tests for HIV have been developed; each improves incrementally on its predecessor(s) in terms of performance and shortening of the window period 3,8 (Figure 2). The official nomenclature for HIV testing is currently changing, with categorizations based on analytic target(s) instead of generation numbers.…”

“…For POC tests, the detection reagent is often a conjugate of protein A (an immunoglobulin-avid, recombinant bacterial peptide) with colloidal gold or selenium. 3 The increased purity of synthetic antigens contributed to a shortening of the median window period from 45 days for viral lysate assays (such as the Western blot) 10 to 31 days with current IgG sensitive POC tests. 4 The antibody-based supplemental test (which has replaced the Western blot in the US testing algorithm 8 ), is a specialized, rapid, IgG sensitive laboratory assay featuring multiple recombinant antigens from both HIV-1 and HIV-2.…”

“…3 POC tests are portable and easy to use, and the ability to perform HIV testing on oral transudate or fingerstick whole blood eliminates the need for venipuncture and the handling, processing, or storage of blood. This can make the entire encounter self-contained, allowing for anonymous testing where permitted by law.…”

Human Immunodeficiency Virus

“…Later, the introduction of luminescent chemicals for detection in chemiluminescence assays offered shorter incubation and reaction times, decreasing test turnaround time. In addition, third-generation assays detect patient IgG and IgM, allowing for earlier detection of HIV antibody production, well before WB positivity, and reducing the window period to 3 to 4 weeks (18,19).…”