UW-Madison researchers develop saliva testing to screen for COVID-19

MADISON, Wis. – University of Wiconsin-Madison researchers are testing volunteers for COVID-19 with a new saliva test, hoping to increase the frequency of testing and speed of results in our community.

Teams are testing volunteers at three sites on campus, along with staff at a local elementary school, planning to expand testing to children, as well as to coaches and players at UW athletic facilities.

Dave O’Connor, a professor in the Department of Pathology and Laboratory Medicine, works in the AIDS Vaccine Research Laboratory studying emerging viruses and their impact. Still, the work he’s currently doing wasn’t expected.

“If you told me a year ago we would be testing for a novel, potentially-fatal coronavirus behind a bike shed in 2020, I would have thought that would be absolutely bonkers,” O’Connor said.

O’Connor’s wife, Shelby O’Connor, is an assistant professor in the same department co-leading the project.

“The last month has been a whirlwind,” she said.

She explained volunteers spit into “little, what we call pointy straws, which are pipette tips, and we collect that into a tube.”

Instead of using specialized instrumentation to conduct polymerase chain reaction, or PCR, as used for diagnostic swab tests, researchers test the saliva using reverse-transcriptase loop-mediated isothermal amplification, or RT-LAMP. Using that method, Dave and Shelby O’Connor said after a few simple steps, a color-change in the test tube will show the results of the test in a matter of hours.

“It is a little more of a simple type of test you train non-scientists to do,” said Dawn Dudley, a senior scientist in the same department. “That would be the point, if you can do this on site at a workplace you could get test results back quickly.”

Dudley helped adapt the test to use saliva. She said it’s more feasible to use more often with patients than the swab test and that frequent testing offers a better shot at detecting the virus and quarantining those who test positive more quickly.

“A test is a snapshot in time, and I think that’s a great advantage of a test like this,” she said. “For frequent testing, saliva is the way to go and easy to get.”

The test is non-diagnostic, meaning if patients tests positive, it’s a good indicator they have the virus, but they will still have to confirm that with a diagnostic test, like those given at hospitals and public testing sites.

Dave O’Connor said the test will still detect the virus in the most contagious patients, who can be connected with most community spread.

“Testing like this will hopefully be able to identify them more quickly because you can test more people, you can do it more quickly and you can find the people at greatest risk,” he said, adding that the rapid testing can take some pressure off of diagnostic testing.

“You can imagine testing 100 people, and if 95 people are cleared by this testing, then that’s 95 people the diagnostic tests don’t necessarily need to handle if those people are at very low risk,” Dave O’Connor said. “But that requires some flexibly in thinking about how testing can work, as well as some understanding that testing like this is really most akin to getting a fever check when you walk into a building.”

Researchers hope this testing could be done in workplaces and schools to safely bring people back, but said more work has to be done first.

“The success is, every day we have a negative test result, we have no positives, everyone’s looking negative every day,” Shelby O’Connor said. “I think that would be a success, but we can’t get to that point until community cases have been driven down.”

She and Dave O’Connor stressed the saliva testing is still in the research phase and they’re looking into how feasible putting this type of testing into place is.

“Are people really going to want to come in and spit into a pointy straw every day they go into a workplace or everyday they go onto the athletic field?” Shelby O’Connor said. “I have no idea.”

Salus, a Madison-based company, is working to make the saliva test more accurate.