Elsevier

Journal of Clinical Virology

Volume 97, December 2017, Pages 22-25
Journal of Clinical Virology

Full length article
Detection and differentiation of HIV-2 using the point-of-care Alere q HIV-1/2 Detect nucleic acid test

https://doi.org/10.1016/j.jcv.2017.10.013Get rights and content

Highlights

  • The Alere q HIV-1/2 Detect is a rapid point-of-care HIV nucleic acid test.

  • It can qualitatively detect and differentiate HIV-1 and HIV-2 in whole blood or plasma samples.

Abstract

Background

The Alere q HIV-1/2 Detect test (Alere Detect) is a rapid point-of-care (POC) nucleic acid test (NAT) that can detect and differentiate HIV-1 and HIV-2 in 25-μL whole blood or plasma samples. The Alere Detect test has been validated for early infant diagnosis of HIV-1 infection, and it is the only POC NAT device currently known to detect HIV-2, which is endemic in West Africa.

Objectives

To evaluate the sensitivity detecting HIV-2 RNA and the differential performance of the Alere Detect.

Study design

Plasma samples from non-HIV (n = 4), HIV-1 (n = 22), HIV-2 (n = 111; 29 Group A, 2 Group B) and HIV-1/HIV-2 dually-seropositive (n = 8) participants in Senegal and the United States and HIV-2 reference strains (3 Group A, 1 Group B) were tested by Alere Detect, Abbott RealTime HIV-1 and the University of Washington HIV-2 RNA quantitative (UW HIV-2) assays.

Results

The Alere Detect correctly differentiated between HIV-1 and HIV-2 in all 80 (100%) patient samples with detectable HIV RNA (n = 20 HIV-1, 60 HIV-2). The overall HIV-2 detection concordance between Alere Detect and the UW HIV-2 assay was 68% (54/80); the concordance improved to 100% (30/30) for samples with HIV-2 RNA >300copies/mL. Neither assay detected HIV-2 RNA in 31 of 111 HIV-2 seropositive samples.

Conclusions

The Alere Detect test is a novel device detecting HIV RNA in clinical samples, and differentiating HIV-1 and HIV-2 with a high level of specificity. It has the potential for use as a rapid HIV-2 NAT-based diagnosis tool in resource-limited settings and to confirm HIV-2 infection for the CDC 4th generation HIV-1/2 diagnostic algorithm.

Introduction

HIV-2 is endemic in West Africa with limited global spread primarily to countries with socio-economic ties to the region [1], [2], [3], [4]; there are an estimated 1–2 million patients infected with HIV-2 worldwide [5], [6], [7]. Compared to HIV-1, patients infected with HIV-2 often have a longer asymptomatic stage, slower decline in CD4 + T-cells and decreased acquired immunodeficiency syndrome (AIDS)-associated mortality [8], [9], [10], [11]. In areas where HIV-2 and HIV-1 co-circulate, a substantial number of patients are dually-infected with both HIV types [12], [13], [14]. The correct differentiation between HIV-1 and HIV-2 infection is critical for diagnosis, antiretroviral therapy (ART) and medical management of HIV-infected individuals [15].

Current methods for distinguishing between HIV-1 and HIV-2 rely on differential immunoassays with varying sensitivity and specificity [16], [17]. The Alere q HIV-1/2 Detect (Alere Detect) test is a rapid point-of-care (POC) nucleic acid test (NAT) providing several advantageous characteristics for HIV diagnosis: 1) the requirement for only 25 microliters plasma or whole blood per test; 2) test completion within one hour; 3) detection and differentiation of HIV-1 Group M/N, HIV-1 Group O and HIV-2 nucleic acid; and 4) the only currently available POC NAT able to detect HIV-2 [18]. Two studies have demonstrated the feasibility of the Alere Detect test to diagnose HIV-1 infection for HIV-1-exposed infants in South Africa and Mozambique [19], [20]. Here, we evaluated the performance of the Alere Detect test for the detection of HIV-1 and HIV-2 in plasma samples collected from HIV-1, HIV-2 and differentiation of HIV-1 from HIV-2, in dually-seropositive patients.

Section snippets

Objectives

Our objectives were to evaluate the sensitivity detecting HIV-2 RNA in plasma samples and the differential performance between HIV-1 and HIV-2 RNA by the Alere q HIV-1/2 Detect.

Patient HIV samples and controls

Clinical plasma samples from HIV-seronegative, HIV-1, HIV-2 and HIV-1/HIV-2 dually-seropositive patients from Senegal and the United States were tested. All study subjects were provided written informed consent, and specimens were collected with human subject approval from the UW Institutional Review Board and the Senegalese Ministry of Health Ethic Committee (CNERS). All clinical specimens were de-identified as required by the UW Humans Subjects Division.

Senegalese HIV-2 and HIV-1/HIV-2

Qualitative detection of HIV-2 RNA in plasma samples

Of 111 plasma samples collected from HIV-2 seropositive patients, 31 samples (27.9%) were not detected by either the Alere Detect or the UW HIV-2 assay (Table 1). Of the 80 total samples detected or quantified by the UW HIV-2 assay (median = 108 copies/mL, range: <10–96,000 copies/mL), 54 samples (67.5%) were detected by the Alere Detect. The overall concordance for detection between the Alere Detect and the UW HIV-2 assay was 54/80 (68%; 95%CI. 56.1% to 77.6%); the concordance improved to 42/46

Discussion

In this study, we evaluated the ability of the Alere q HIV-1/2 Detect, a rapid POC NAT platform, to detect and differentiate HIV-1 from HIV-2 RNA in plasma samples collected from HIV-infected persons. To our knowledge, this is the first study of a device that detects and differentiates HIV-1 and HIV-2 nucleic acid, which makes this device suitable for use in HIV-2 endemic regions. The 4th-generation (2014) CDC algorithm for HIV diagnostic testing differentiates HIV-1 from HIV-2 infection [25],

Conflict of interest

All authors approved the final manuscript.

Financial disclosures

This study was supported by grants from the National Institutes of Health/National Institute of Allergy and Infectious Diseases (AI-060466) and Alere Technologies, GmbH (GSG); and the University of Washington Center for AIDS Research (AI-027757) and AIDS Clinical Trials Group Laboratory Center (AI-106701) (RWC) and AI-068618. Dr. Gottlieb has received funding and research support from Gilead Sciences (USA), Merck & Co. (USA), Janssen Pharmaceutica (Belgium), Cerus Corp. (USA), Alere, GmbH

Competing interests

None.

Ethical approval

UW IRB and the Senegal EC (CNERS).

Acknowledgements

We thank the study participants, families and study staff. The members of the UW-Dakar HIV-2 Study Group also includes: Fatou Traore, Khadim Faye, Marie Pierre Sy, Bintou Diaw, Mbaye Ndoye, Amadou Bale Diop, Marianne Fadam Diome (Clinique des Maladies Infectieuses Ibrahima DIOP Mar, CHNU Fann, Universite Cheikh Anta Diop de Dakar, Dakar, Senegal); Jean Philippe Diatta, Raphael Bakhoum, Juliette Gomis, (Région Médicale de Ziguinchor, Ziguinchor, Casamance, Senegal), Stephen Hawes, Noelle

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  • Cited by (0)

    1

    Current affiliation: BLINK AG, Germany.

    2

    Current affiliation: Dekra Certification GmbH, Germany.

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