title: Performance of the SAMBA I and II HIV-1 Semi-Q Tests for viral load monitoring at the point-of-care.
abstract: Although access to antiretroviral therapy for HIV infection is increasing in resource-poor countries, viral load testing for monitoring of treatment efficacy remains limited, expensive, and confined to centralized laboratories. The SAMBA HIV-1 Semi-Q Test is a nucleic acid-based amplification assay developed for viral load monitoring performed on either the semi-automated SAMBA I system for laboratory use or the fully automated SAMBA II system for point-of care use. We have assessed the performance characteristics of the SAMBA HIV-1 Semi-Q Test on SAMBA I and SAMBA II systems according to the Common Technical Specifications of the European Community's 98/79 In Vitro Diagnostic Medical Devices Directive. The sensitivity, specificity, reproducibility, and viral subtype coverage of the test were similar on the SAMBA I and SAMBA II platforms. The clinical performance on the SAMBA I system was compared with the Roche CAP/CTM assay and evaluated in-house with 130 patient specimens from London as well as in the field with 390 specimens in Kenya and Zimbabwe. The overall concordance between the SAMBA and CAP/CTM assays was 98.1%. The clinical performance of the test on the SAMBA II platform in comparison with the Abbott HIV-1 RealTime Assay was evaluated in-house with 150 specimens from Ukraine, yielding a concordance of 98.0%. The results thus show that the SAMBA HIV-1 Semi-Q Test performs equivalently on SAMBA I and SAMBA II, and they suggest that the test is suitable for implementation at the point-of-care in resource-poor regions where viral load testing is desperately needed but often unavailable.
authors.affiliation: Diagnostics Development Unit, Department of Haematology, University of Cambridge, Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK.
authors.forename: Neha
authors.initials: N
authors.lastname: Goel
authors.affiliation: Diagnostics Development Unit, Department of Haematology, University of Cambridge, Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK.
authors.forename: Allyson V
authors.initials: AV
authors.lastname: Ritchie
authors.affiliation: National Microbiology Reference Laboratory, Southerton, Harare ST749, Zimbabwe.
authors.forename: Sekesai
authors.initials: S
authors.lastname: Mtapuri-Zinyowera
authors.affiliation: Kenya Medical Research Institute/US CDC Research and Public Health Collaboration (KEMRI-CDC), Kisumu, Kenya.
authors.forename: Clement
authors.initials: C
authors.lastname: Zeh
authors.affiliation: Kiev Regional AIDS Center, Kyiv, Ukraine.
authors.forename: Tetiana
authors.initials: T
authors.lastname: Stepchenkova
authors.affiliation: Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Lehga
authors.affiliation: Department of Genitourinary Medicine and HIV, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, UK.
authors.forename: Annemiek
authors.initials: A
authors.lastname: De Ruiter
authors.affiliation: Diagnostics Development Unit, Department of Haematology, University of Cambridge, Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Farleigh
authors.affiliation: Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Edemaga
authors.affiliation: Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA.
authors.forename: Rosario
authors.initials: R
authors.lastname: So
authors.affiliation: Diagnostics for the Real World (Europe) Ltd., Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sembongi
authors.affiliation: Diagnostics Development Unit, Department of Haematology, University of Cambridge, Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK; Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA.
authors.forename: Craig
authors.initials: C
authors.lastname: Wisniewski
authors.affiliation: Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Nadala
authors.affiliation: Division of AIDS, Henry M. Jackson Foundation for Advancement of Military Medicine, National Institutes of Health, Fishers Lane, Rockville 5601, MD, USA.
authors.forename: Marco
authors.initials: M
authors.lastname: Schito
authors.affiliation: Diagnostics Development Unit, Department of Haematology, University of Cambridge, Science Village, Chesterford Research Park, Little Chesterford CB10 1XL, UK; Diagnostics for the Real World Ltd., 840 Del Rey Avenue, Sunnyvale 94085, CA, USA. Electronic address: hl207@cam.ac.uk.
authors.forename: Helen
authors.initials: H
authors.lastname: Lee
mesh_terms: D057205:Automation, Laboratory / Q000379:methods; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D007630:Kenya; D008131:London; D019095:Point-of-Care Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014455:Ukraine; D019562:Viral Load / Q000379:methods*; D015030:Zimbabwe
keywords: Diagnosis; HIV-1; Point-of-care; Therapy monitoring; Viral load