90-minute COVID-19 test has high sensitivity, specificity
A rapid, 90-minute COVID-19 test was shown to have 94% sensitivity and 100% specificity, according to research published in Lancet Microbe.
“These results suggest the test, which can be performed at a patient’s bedside without the need to handle any sample material, has comparable accuracy to standard laboratory testing,” Graham S. Cooke, MD, PhD, a National Institute of Health Research professor of infectious diseases in the department of infectious disease at Imperial College London, said in a press release.
Cooke and colleagues obtained two nasopharyngeal swab samples each from participants in three hospitals who were self-referred health care workers with suspected COVID-19, patients who presented to the ED with suspected COVID-19, or hospital inpatients with or without suspected COVID-19.
For the test, known as the CovidNudge, patient sample swabs were inserted directly into a cartridge that contained all the components required for RT-PCR reactions. This included technical replicants of seven SARS-CoV-2 gene targets and human ribonuclease P control, which helped to ensure the adequacy of patient samples.
Samples were tested using both the CovidNudge platform and standard laboratory platforms.
Researchers collected 386 paired samples, with 67 samples testing positive on the CovidNudge point-of-care platform and 71 samples testing positive on standard laboratory tests.
Cooke and colleagues determined that the overall sensitivity of CovidNudge was 94% (5% CI; 86–98) and the overall specificity was 100% (95% CI; 99–100).
They found that the sensitivity of the CovidNudge test varied by group, with a sensitivity of 93% in health care workers (95% CI; 84–98), 100% in ED patients (95% CI; 48–100) and 100% in hospital inpatients admissions (95% CI; 29–100).
The specificity of the test was consistent among all three participant groups.
Cooke and colleagues found that the performance of point-of-care testing was similar during periods when there was a high background prevalence of laboratory positive tests (25%; 95% CI, 20–31) and a when there was a low prevalence in laboratory positive tests (3%; 95% CI, 1–9).
According to the press release, the test is currently used in eight hospitals in London and will be rolled out nationwide across the United Kingdom.
“Many tests involve a trade-off between speed and accuracy, but this test manages to achieve both,” Cooke said in the press release. “Developing an effective bedside test in under three months has been an incredible collaboration between teams of engineers, clinicians and virologists.”