Utility of the FebriDx point-of-care test for rapid triage and
identification of possible coronavirus disease 2019 (COVID-19)
Abstract
Abstract Background Differentiating viral from bacterial acute
respiratory infections (ARIs) remains challenging, due to the
non-specific clinical manifestations. The COVID-19 pandemic is putting
extraordinary strain on healthcare resources. To date, molecular testing
is available but has a long turnaround time and therefore cannot provide
results at the point-of-care (POC) thereby exposing
COVID-19/Non-COVID-19 patients to each other while awaiting diagnosis.
Methods This observational study prospectively evaluated the utility of
a triage strategy including FebriDx, a POC fingerstick blood test that
differentiates viral from bacterial ARIs through simultaneous detection
of Myxovirus-resistance protein A (MxA) and C-reactive protein (CRP), in
rapidly determining viral cases requiring immediate isolation and
confirmatory molecular testing, from non-infectious patients or
bacterial infections requiring antibiotics. Results 75 consecutive
patients were screened, 48 eligible cases were tested with FebriDx, 36
were confirmed viral infection and 35/36 had COVID-19. 31/35 COVID-19
cases tested positive for SARS-CoV-2 via rRT-PCR and (4/35) had a
clinical diagnosis of probable COVID-19 based on symptoms,
epidemiological history, and chest imaging (PPV 100% (35/35)). 13 cases
were FebriDx viral negative and rRT-PCR was also negative. In one case,
it was not possible to determine the exact cause of infection, although
a viral infection could not be excluded. Including this patient, FebriDx
NPV was 92.3% (12/13), exceeding the NPV of rRT-PCR a 68.3% (13/19),
and diagnostic sensitivity was conservatively calculated at 97% (35/36)
compared to 82.9% (29/35) for initial rRT-PCR. The diagnostic
specificity of both FebriDx and rRT-PCR was 100%. Conclusions: FebriDx
could be deployed as part of a reliable triage strategy for identifying
possible COVID-19 patients with symptomatic ARI in the COVID-19
pandemic. Key words: Pandemic; COVID-19; SARS-CoV-2; pneumonia; viral;
point of care; infection