MSU Saliva Test Offers Non-Intrusive Scan For COVID-19

Aug 28, 2020

Michigan State University begins its fall semester next week under the shadow of COVID-19.  A team of researchers is working on a saliva test than can track the coronavirus from a group of people back to infected individuals. 


The standard COVID-19 nasal swab is a pain in the nose.  It’s uncomfortable, and can make you cough and sneeze.

 

Dr. Jack Lipton understands that.

 

He’s a professor of translational neuroscience at Michigan State University’s research site in Grand Rapids.  He figured there had to be a painless way to collect COVID samples. 

 

Turns out, there is.

 

“A couple of other laboratories were using saliva and they were getting good yield of virus from those samples,” says Lipton.

 

Lipton heads what he and his colleagues have dubbed “The Spartan Spit Team.”  They’re developing a test kit for analyzing saliva.  It’s a cardboard box with a tube to collect the sample. 

 

Unlike an individual swab test, saliva collection can test a pool of donors.  Samples are analyzed using digital droplet polyermase chain reaction (PCR) machines.

 

First, though, saliva must be broken down into a thinner form.  There’s an enzyme that breaks it down naturally, but it’s hard to come by. 

 

So the team has come up with a mechanical solution to make the spit less gooey: beads. 

 

“They’re made out of ceramic and they're a three-millimeter bead,” says research associate Allyson Cole-Strauss.  “We have to put four of these into every single one of those sample collection tubes.”

 

Saliva donors are placed into two different pools of eight to 12 people.  If one pool turns up positive, then each person must be tested individually.  But if two pools light up, that intersection can be traced to a single individual.

 

This graph depicts 96 saliva samples. If two test pools intersect at a common point, it may indicate a positive case of COVID-19.
Credit Courtesy / MSU Dept. of Translational Neuroscience

 

However, even if someone tests positive with a saliva kit, there’s still one more step to make sure. 

 

“It’s a screening test,” says Ingham County Health Officer Linda Vail.  “Because of the less specificity and sensitivity of the test, then typically what you’ll see is somebody go on and get a confirmatory test after that.”

 

Vail says the county is working with MSU to develop a procedure for conducting those confirmatory tests.

 

If we wait for people to get symptoms, we are going to be way too late by the time we find them. This gives us a chance to get in there and act quickly.

Lipton’s team plans to run up to 10,000 samples a week.  He says he doesn’t expect the university’s decision to move undergraduate courses online to alter that projection. 

 

The saliva test is voluntary, so Lipton is appealing to the MSU community’s social conscience to make it a success.  He’s urging people to return their kits the day they produce their sample.  Lipton says cooperation is vital in a situation in which many people may be asymptomatic.

 

“If we wait for people to get symptoms, we’re going to be way too late by the time we find them,” Lipton says.  “So, this gives us a chance to get in there and act quickly.”