Development and deployment of a rapid recombinase polymerase amplification Ebola virus detection assay in Guinea in 2015

Abstract

In the absence of a vaccine or specific treatments for Ebola virus disease (EVD), early identification of cases is crucial for the control of EVD epidemics. We evaluated a new extraction kit (SpeedXtract (SE), Qiagen) on sera and swabs in combination with an improved diagnostic reverse transcription recombinase polymerase amplification assay for the detection of Ebola virus (EBOV-RT-RPA). The performance of combined extraction and detection was best for swabs. Sensitivity and specificity of the combined SE and EBOV-RT-RPA were tested in a mobile laboratory consisting of a mobile glovebox and a Diagnostics-in-a-Suitcase powered by a battery and solar panel, deployed to Matoto Conakry, Guinea as part of the reinforced surveillance strategy in April 2015 to reach the goal of zero cases. The EBOV-RT-RPA was evaluated in comparison to two real-time PCR assays. Of 928 post-mortem swabs, 120 tested positive, and the combined SE and EBOV-RT-RPA yielded a sensitivity and specificity of 100% in reference to one real-time RT-PCR assay. Another widely used real-time RT-PCR was much less sensitive than expected. Results were provided very fast within 30 to 60 min, and the field deployment of the mobile laboratory helped improve burial management and community engagement.

Biosafety standards for working with Crimean-Congo hemorrhagic fever virus

“…Organizations such as the Centers for Disease Control and Prevention, USA, the National Institutes for Health, USA, the World Health Organization and the European Committee for Standardization should revise international recommendations accordingly. Technical advances arising from the successful deployment of mobile BSL-3 laboratories in the West African outbreak of Ebola disease (Chen et al, 2015;Faye et al, 2015;Inglis, 2015;Wölfel et al, 2015) should be exploited to derive cost-effective improvements to diagnostic laboratories in the CCHF endemic countries. In particular, the use of flexible-walled or hard plastic glove boxes for extraction of nucleic acids and inactivation of sera would greatly improve laboratory safety.…”

“…Of 11 laboratories performing virus isolation and propagation, six did so in BSL-4 facilities and five in lowergrade facilities (Fernandez-Garcia et al, 2012). Enquiries made for purposes of the present review revealed that in Slovenia, Turkey and Senegal, CCHFV diagnostic samples were handled at BSL-2 for years before a BSL-3 laboratory was finally available for research.…”

“…Reported CFRs include 25 % from South Africa (Burt, 2015), 26 % from Kosovo (Humolli, 2015) and 15 % from Iran and Bulgaria (Sadegh, 2015;Christova, 2015). A structured epidemiological investigation in South Africa revealed that all or most infections in that country result in clinical disease (Fisher-Hoch et al, 1992). Analysis of ProMED entries on CCHF from 1998 through 2013 reveals a CFR of 13 % among 3426 cases reported from Turkey, Russia, Iran, Pakistan and Afghanistan (Ince et al, 2014).…”

INMI/Emergency NGO Italian Laboratory Established In Sierra Leone during Ebola Virus Disease Outbreak in West Africa

“…For this purpose, all of the deceased in districts of Conakry most recently affected by the Ebola virus outbreak had to be tested. The field deployment of a mobile suitcase laboratory using RPA which provided results in 30-40 minutes helped to improve burial management and community engagement in the Matoto district in Conakry [30].…”

The Pasteur Laboratory associated with the Ebola Treatment Center of Macenta (Guinea)

“…In this context, the IPD laboratory and collaborators adapted and optimised a rapid test based on isothermal reverse transcription recombinase polymerase amplification (RT-RPA) for the detection of Ebola virus [11,12]. A mobile laboratory consisting of a mobile glove box and a Diagnostics-in-Suitcase (DiaS) powered by a battery and solar panel was used.…”