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The researchers, from the University of Colorado Boulder, report their development in a preprint article that has yet to be peer reviewed.
While scientists are working to develop vaccines for SARS-CoV-2 and treatments for the disease that it causes, COVID-19, they are also trying to develop more effective testing procedures.
Until an effective vaccine and treatment protocol are developed, emergency measures will likely continue, in order to counter reoccurring waves of the pandemic. In addition to social distancing and good hygiene, widespread testing can help limit the spread of the virus.
Preprint research has suggested that up to 70% of people with SARS-CoV-2 who are younger than 60 could be asymptomatic. Testing as many people in a community as possible can identify asymptomatic people, who can then self-isolate to curb the virus’ spread.
When it comes to testing, time is of the essence. Findings of a different preprint study suggest that the speed of results is crucial: The longer a person does not know that they have the virus, the longer they can infect other people.
In the United States, the current turnaround time for results is slow. According to the researchers behind the present study:
“Many SARS-CoV-2 tests require that biospecimens be collected, transported to centralized labs, logged, queued, processed, analyzed, and then [the] results [are] communicated back to the agency that sent the sample for testing and finally delivered to the person who had the test.”
Now, however, the University of Colorado Boulder team has developed a SARS-CoV-2 test that can produce a result in 45 minutes.
Moreover, it requires no expensive, complicated equipment, meaning that it could be deployed widely in communities, not only in laboratories and hospitals.
According to Prof. Sara Sawyer, senior author of the research and a virologist at the university’s Department of Molecular, Cellular, and Developmental Biology, “Every test that has been approved to date requires that the sample, even if it’s saliva, be processed in a clinical diagnostic lab or at a doctor’s office, using sophisticated equipment. That can take up to 9 days right now.”
Nicholas Meyerson, Ph.D., the lead author of the research, adds:
“We are facing a serious testing shortage in this country right now, as more people want to get tested and diagnostics labs are overwhelmed. We’ve developed a test that could get results to people much faster.”
This experimental test requires a person to spit into a tube, add a solution, seal the tube, and return it for analysis.
Testing staff then run the test using pipettes, a heating source, and an enzyme mixture — all of which are readily available and easy to transport.
The aim is to identify specific regions of the SARS-CoV-2 genome. If the test is positive, the reaction tubes turn from pink to yellow. If the test is negative, the tubes stay pink.
To check the effectiveness of the test, the researchers added an inactive form of SARS-CoV-2 at various concentrations to 30 out of 60 saliva samples, randomized the samples, then gave them to colleagues to test.
“The test predicted with 100% accuracy all of the negative samples, and 29 of [the] 30 positive samples were predicted accurately,” says Meyerson.
A second party are currently validating the researchers’ findings.
Although the test appears to be slightly less sensitive than current COVID-19 tests, the researchers argue that its ability to produce rapid results is more important, when it comes to restricting the spread of the virus.
According to Prof. Roy Parker, director of the university’s BioFrontiers Institute:
“Our modeling showed that whether a test is sensitive or supersensitive is not that important. What is important is frequent testing, with the test results returned as fast as possible, which identifies more infected people faster and can limit new infections.”
Dr. Parker and colleagues have demonstrated this in a preprint article, which is also awaiting peer review.
Nonetheless, if the findings are verified following peer review then they will be valuable in helping to significantly increase both the number of SARS-CoV-2 tests available to a country and the speed with which their results can be returned.