A Rapid and Automated Sample-to-result HIV Load Test for Near-patient Application

Background: Current viral load tests for human immunodeficiency virus (HIV) can only be performed in laboratory environments, require highly trained operators and expensive equipment, and have a turnaround time of several hours to days. The Liat HIV Quant Assay proves that such nucleic acid testing can be performed rapidly and easily, allowing application at the point of care.

Methods: The Liat Analyzer automates the entire assay, including sample preparation, amplification, and detection, in a self-contained and closed-tube system. Dynamic range, limit of detection, and subtype specificity were evaluated. Clinical samples were tested retrospectively to correlate the result of this assay with those of commercial HIV load assays.

Results: The Liat assay demonstrated linearity of >6 logs (R(2), 0.98) and a limit of detection of 57 copies/mL. HIV-1 group M (clades A-H), group O, and HIV-2 were detected. Testing of clinical samples showed a high degree of concordance between the copy numbers detected by the Liat assay and those detected by the Siemens and Roche assays (92.0% and 88% correlation coefficient of the log copy number, respectively). The time from sample collection to result was 88 min.

Conclusions: Results suggest that the Liat HIV Quant Assay has performance equivalent to that of commercial HIV load assays and significantly reduces assay time, simplifies test operation, and provides biocontainment to allow operation in nonlaboratory settings.