Establishing Ebola Virus Disease (EVD) diagnostics using GeneXpert technology at a mobile laboratory in Liberia: Impact on outbreak response, case management and laboratory systems strengthening

Abstract

The 2014–16 Ebola Virus Disease (EVD) outbreak in West Africa highlighted the necessity for readily available, accurate and rapid diagnostics. The magnitude of the outbreak and the re-emergence of clusters of EVD cases following the declaration of interrupted transmission in Liberia, reinforced the need for sustained diagnostics to support surveillance and emergency preparedness. We describe implementation of the Xpert Ebola Assay, a rapid molecular diagnostic test run on the GeneXpert platform, at a mobile laboratory in Liberia and the subsequent impact on EVD outbreak response, case management and laboratory system strengthening. During the period of operation, site coordination, management and operational capacity was supported through a successful collaboration between Ministry of Health (MoH), World Health Organization (WHO) and international partners. A team of Liberian laboratory technicians were trained to conduct EVD diagnostics and the laboratory had capacity to test 64–100 blood specimens per day. Establishment of the laboratory significantly increased the daily testing capacity for EVD in Liberia, from 180 to 250 specimens at a time when the effectiveness of the surveillance system was threatened by insufficient diagnostic capacity. During the 18 months of operation, the laboratory tested a total of 9,063 blood specimens, including 21 EVD positives from six confirmed cases during two outbreaks. Following clearance of the significant backlog of untested EVD specimens in November 2015, a new cluster of EVD cases was detected at the laboratory. Collaboration between surveillance and laboratory coordination teams during this and a later outbreak in March 2016, facilitated timely and targeted response interventions. Specimens taken from cases during both outbreaks were analysed at the laboratory with results informing clinical management of patients and discharge decisions. The GeneXpert platform is easy to use, has relatively low running costs and can be integrated into other national diagnostic algorithms. The technology has on average a 2-hour sample-to-result time and allows for single specimen testing to overcome potential delays of batching. This model of a mobile laboratory equipped with Xpert Ebola test, staffed by local laboratory technicians, could serve to strengthen outbreak preparedness and response for future outbreaks of EVD in Liberia and the region.

European Union training programme for tuberculosis laboratory experts: design, contribution and future direction

“…Resilient laboratory systems are critical to support TB programmes, infectious disease diagnostics and public health systems. Global Health crises such as the current Coronavirus disease 2019 (COVID-19) Pandemic and the 2014-16 West Africa Ebola outbreak highlight the importance of functional laboratory systems and diagnostic capabilities [19][20][21][22]. Unfortunately, laboratory systems and infrastructure have long been neglected and under-resourced in many settings.…”

Integrated Use of the GeneXpert Platform for TB, HIV and EVD testing in Liberia

“…However, the country faced another outbreak in June 2015, was declared free of transmission on September 2015, experienced three more cases in November 2015 and was again declared Ebola-free on January 2016.The magnitude as well as the frequent re-emergence of the EVD outbreak indicated the need for building sustained diagnostics to support surveillance and emergency preparedness. This can be achieved by building the capacity of clinical laboratory in such a way to shift in addressing any occurrence or re-occurrence of epidemic as well as emerging diseases [17].…”

“…Running the GeneXpert by Liberian nationals makes the preparedness and response to any future outbreak very sustainable. The integrated use of GeneXpert platform at EVD isolation facilities has strengthened preparedness and early response capabilities for future EVD outbreaks in Liberia [17]. the HIV 1 Viral load reagents and consumables were expired.…”

Development and Evaluation of a Duo Zaire ebolavirus Real-Time RT-PCR Assay Targeting Two Regions within the Genome

“…The assay correctly identified five different EBOV strains, Yambuku-Mayinga, Makona-C07, Yambuku-Ecran, Gabon-Ilembe, and Kikwit-956210, and correctly excluded all non-EBOV isolates tested [24]. Subsequently, the Xpert ® Ebola assay was used in the comparative study versus TaqMan RT-qPCR assays [25]) and in field studies [26][27][28]. Our aim in this study was not to challenge the Xpert ® Ebola with the Duo Gibb + Huang assay but to evaluate how complex it would be to transfer a test that was operational in a classic real-time TaqMan platform onto a Flex open cartridge provided with the Noro Bead EZR enzyme beads.…”