PARIS - A 15-minute, on-the-spot blood test for Ebola was as accurate in a patient trial as the most widely used laboratory-based test, its US developers said yesterday.
An affordable, rapid diagnostic test would be invaluable to health workers on the ground, allowing them to quickly identify and isolate infected individuals and curtail the spread of the deadly haemorrhagic virus.
Named ReEBOV, the kit manufactured by Colorado-based Corgenix works with a drop of blood from a finger prick and a test strip that changes colour in five to 15 minutes. It requires little training to use, although one potential drawback is that it needs refrigeration.
The standard test in use today, RealStar RT-PCR, requires analysis of much larger blood samples at a laboratory with a high biosafety level and trained staff - facilities often not within easy reach of outbreak zones.
"Laboratory results can sometimes take days to return," said a press statement issued by The Lancet medical journal, which published the study results.
For the trial, Dr Nira Pollock, of the Boston Children's Hospital, and a team used both the ReEBOV and RealStar tests on 105 suspected Ebola patients in February at two government treatment centres in Sierra Leone - one of three countries hardest hit by the current outbreak.
ReEBOV detected all 28 Ebola cases diagnosed by RealStar - a 100 per cent level of sensitivity - but much faster.
However, the research also revealed disconcerting data on the reliability of RealStar, which is manufactured by German company altona Diagnostics.
Six of the 77 RealStar-negative cases tested positive with ReEBOV. And further checks with an alternative RealStar-like test called Trombley, not yet in wide use, revealed a handful of cases with low virus levels that were missed by the other tests.
This meant that the team could not determine how accurate ReEBOV is in patients in the early phase of infection when virus levels are low.
While other prototype fast-track tests are being developed and tested, ReEBOV is the only one to have been granted emergency-use status by the World Health Organisation.