Fingerstick Rapid Diagnostic Test for Ebola Virus Disease Performs Well in the Field

Mary E. Wilson, MD reviewing Broadhurst MJ et al. Lancet 2015 Jun 25. Bhadelia N. Lancet 2015 Jun 25.

The ReEBOV point-of-care rapid diagnostic test for EVD had 100% sensitivity and 92% specificity in a small study population, as well as in reference-laboratory samples.

Currently, diagnosis of Ebola virus disease (EVD) requires venipuncture to collect blood for reverse-transcriptase polymerase chain reaction (RT-PCR) testing, which potentially exposes health workers and laboratory technicians to infective blood. The ReEBOV Antigen Rapid Test — a dipstick immunoassay — detects Ebola virus VP40 matrix protein antigen in whole blood collected by fingerstick or venipuncture or in plasma.

Using manufacturer-supplied test kits, investigators assessed ReEBOV performance in two Ebola care facilities in Sierra Leone. Patients who met the EVD case definition (N=105) had whole blood samples collected via venipuncture for RT-PCR and fingerstick samples obtained for the rapid diagnostic test. ReEBOV results were assessed by two readers, and by a third if results were discrepant. Testing was also performed on 284 consecutive whole blood samples submitted to the Public Health England reference laboratory in Sierra Leone.

In both test scenarios, ReEBOV showed 100% sensitivity and 92% specificity compared with RT-PCR. The ReEBOV positivity score increased with longer duration of illness. Two independent readers agreed about results for 100 of 105 rapid diagnostic tests. An alternative RT-PCR assay showed positive results for 3 of 18 samples that tested negative by both the ReEBOV and the standard RT-PCR.

Citation(s):

Broadhurst MJ et al. ReEBOV antigen rapid test kit for point-of-care and laboratory-based testing for Ebola virus disease: A field validation study. Lancet 2015 Jun 25; [e-pub].

Bhadelia N.Rapid diagnostics for Ebola in emergency settings. Lancet 2015 Jun 25; [e-pub].