FDA Approves First Ebola Test for Emergency Use

FDA announced on Dec. 23, 2014 that it had approved Roche Diagnostics’ Ebola test for emergency use. The LightMix Ebola Zaire rRT-PCR (real-time reverse transcription polymerase chain reaction) test is designed for use in patients with symptoms related to the Ebola Zaire virus. The test has not been FDA-approved for general use; it is made by TIB MOLBIOL and distributed by Roche.

The recent Ebola outbreak in West Africa has driven the need to test for the virus as soon as possible, to ensure proper isolation and treatment. According to Reuters, Roche claims that the test can generate results in a little over three hours. FDA said that this is the first test that it has approved for the detection of Ebola Zaire virus. The test is authorized only for use with EDTA whole blood or TriPure-inactivated blood specimens.

The one-tube assay test reverse-transcribes RNA templates into cDNA copies, which then go through PCR with cyclic heating and cooling to amplify a specific DNA region. The probe anneals to a specific target sequence located between the forward and reverse primers. During the extension phase of the PCR cycle, the 5’ nuclease activity of Taq polymerase degrades the probe, causing the reporter dye to separate from the quencher dye, generating a fluorescent signal. With each cycle, additional reporter dye molecules are cleaved from their respective probes, increasing the fluorescence intensity. Fluorescence intensity is monitored at each PCR cycle.

Sources:
FDAReutersTIB Molbiol