UC Davis unveils rapid test that can identify COVID-19 in 20 minutes

UC Davis unveils rapid test that can identify COVID-19 in 20 minutes

Photo Credits: Quinn Spooner / Aggie. A student spits into a vial during the saliva portion of a COVID-19 test conducted at the Hutchison Drive parking lot screening center on October 8, 2020.

Test can detect both COVID-19 and flu in proteins

On Nov. 12, UC Davis unveiled a rapid COVID-19 test which will be able to check for coronavirus and the flu at the same time. The results will be revealed in just 20 minutes, the university press release said, and the test is one of just a few available in the nation at this time. 

The rapid test, notable for its accuracy, will be used primarily in urgent situations so that doctors and nurses can administer care quickly. 

“We have educated our physicians to use this test when urgent medical decisions need to be made,” said Dr. Nam Tran, an associate clinical professor in the department of pathology and Laboratory Medicine who spearheaded efforts to validate the test, via email. “So this is not just [necessary in] emergency situations. An elderly symptomatic person who would be at risk for COVID-19 and/or influenza would clearly benefit, even if they just had the flu.

Since March, the university has been running studies about the potential rapid test, and has also been testing the accuracy of the cobas Liat (lab in a tube) System in a study sponsored by Roche Diagnostics. UC Davis Health did not respond for comment after multiple requests at the time of publication of this article. 

The new Liat testing device relies on a high-accuracy PCR (Polymerase Chain Reaction)-based method. The PCR method takes place inside a robot operated by skilled clinical laboratory scientists, leaving little room for error. 

These molecular tests rely on the RNA of the coronavirus. In this case, only a very small amount of genetic material is necessary to detect COVID-19. The PCR replicates the RNA from the nasal or throat swab so that it will become visible. 

“By analogy, a microscope magnifies a small microbe so you can see it, PCR in this case ‘magnifies’ the number of DNA or RNA of a pathogen so we can detect it with a test,” Tran said.

According to the press release, most coronavirus tests until now have been antigen-based, using a throat or nasal swab to check for proteins identified with COVID-19. Although antigen tests are inexpensive and can be administered relatively quickly, they are less accurate, with a potential false negative rate of 20%. 

By contrast, the PCR method has become increasingly central to more accurate COVID-19 testing methods, because the tests are nearly 100% accurate. Previously, they took much longer to produce results, but the Liat rapid test expedites the process and can easily detect viral RNA, even among asymptomatic or pre-symptomatic cases of COVID-19. 

Amid a notable spike in coronavirus cases nationwide, the university also recently expanded its testing capacity on-campus, making a rapid saliva-based test available to select subgroups of employees and students who may not be experiencing COVID-19 symptoms. 

According to Vice Chancellor Kelly Ratliff, testing is expected to be made available to all university employees by December, and it will be required for those who use campus facilities. 

“We are all excited about expanding our testing capacity,” said Chancellor Gary May via email.


Written by: Rebecca Bihn-Wallace –– campus@theaggie.org