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bioRxiv · 10.1101/078501

Rapid molecular detection of Zika virus in urine using the recombinase polymerase amplification assay

Ahmed Abd El Wahed·Sabri S. Sanabani·Oumar Faye·Rodrigo Pessoa·Joao-Veras Patriota·Ricardo Rodrigues-Giorgi·Pranav Patel·Susanne Boehlken-Fascher·Olfert Landt·Matthias Niedrig·Paolo M. de A. Zanotto·Claus-Peter Czerny·Amadou A. Sall·Manfred Weidmann
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Abstract

BackgroundCurrently the detection of Zika virus (ZIKV) in patient samples is done by real-time RT-PCR. Samples collected from rural area are sent to highly equipped laboratories for screening. A rapid point-of-care test is needed to detect the virus, especially at low resource settings.\n\nMethodology/Principal FindingsIn this report, we describe the development of a reverse transcription isothermal recombinase polymerase amplification (RT-RPA) assay for the identification of ZIKV. RT-RPA assay was portable, sensitive (21 RNA molecules), and rapid (3-15 minutes). No cross-reactivity was detected to other flaviviruses, alphaviruses and arboviruses. Compared to real-time RT-PCR, the diagnostic sensitivity was 92%, while the specificity was 100%.\n\nConclusions/SignificanceThe developed assay is a promising platform for rapid point of need detection of ZIKV in low resource settings and elsewhere (e.g. during mass gathering).\n\nAuthor SummaryCurrently, Dengue (DENV), Zika (ZIKV) and Chikungunya (CHIKV) viruses represent a global threat. The clinical picture of the acute febrile diseases caused by DENV, ZIKV and CHIKV is very similar, in addition, the same mosquito vector is involved in the transmission cycle. The differentiation between them is of great importance as supportive treatment differs and the identification of any of the three viruses prompts implementation of control measures to avoid spreading of an outbreak. We have developed an assay for the detection of ZIKV genome. The assay based on isothermal \"recombinase polymerase amplification\" assay, which was performed at one temperature (42{degrees}C). The result was obtained in maximum of 15 minutes. Moreover, the assay is easy to be implemented at low resource settings.

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Ahmed Abd El Wahed, Sabri S. Sanabani, Oumar Faye, Rodrigo Pessoa, Joao-Veras Patriota, Ricardo Rodrigues-Giorgi, Pranav Patel, Susanne Boehlken-Fascher, Olfert Landt, Matthias Niedrig, Paolo M. de A. Zanotto, Claus-Peter Czerny, Amadou A. Sall, Manfred Weidmann. 2016-10-03. Rapid molecular detection of Zika virus in urine using the recombinase polymerase amplification assay. https://doi.org/10.1101/078501

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