Update 7:15 p.m. Feb. 20: Cal Poly professors are not able to measure how much COVID-19 is in a person’s body at the time of the test.
Flashback to March of 2020. The COVID-19 virus is an emerging fear throughout the world. The long-term effects are unknown and it is beginning to infiltrate nations rapidly.
Hone into San Luis Obispo, California — a small town on the Central Coast. Biology professor Jean Davidson was approached by a physician from French Hospital. Fears of limited capacity to test for the virus were looming. The hospital posed the following question to the professors: Are you able to develop a homegrown test for the virus?
Davidson approached a fellow biology professor, Nathaniel Martinez, to collaborate with the hope of producing a valid test. They responded to the physician at the hospital with a, “we’ll see.”
Little did they know that the coming weeks would be full of protocols, recruitment of students and the development of a reliable in-house diagnostic test that would be implemented campus-wide.
The Development of the Test
After spending nearly two weeks in the laboratory together, the professors came to the conclusion that an in-house COVID-19 test could be accomplished.
The professors pressed pause and continued their normal teaching schedule for the rest of the year. Cal Poly sent students home for a two week spring break. Then came summer.
August approached Cal Poly and the university was confronted with a crossroad: should students be brought back onto campus? The university administration called the professors in to discuss logistics of an in-house COVID-19 test. The first question was, “can you do this?” next came, “by when can you do this?” and lastly, “how much is this all going to cost?”
After meeting with the administration, the professors set goals. They aspired to create a test with equipment that they already had within the department’s labs while also increasing capacity by changing or eliminating elements of the current protocol on campus.
A few more weeks were spent in the lab developing a saliva test with the instruments they had. The test was modeled after a saliva test developed at Yale University. Then, the university approached them with another question.
“Are you able to get to a point where you are surveilling the campus, students and faculty included, every week?” the administration asked.
This meant that the professors required a test to be valid enough to run 20,000 to 25,000 tests a week, averaging 4,000 tests a day.
A New Kind of Test
Eventually, Cal Poly’s saliva test did not resemble Yale’s model at all. Regardless of the saliva aspect, it was fully developed in-house. The test not only gave binary results — defining a “positive” or “negative” indication of if the saliva sample contained COVID-19, but it was also able to show how much virus is within the individual at the time of testing.
Knowing how much COVID-19 a person is infected with is becoming more important, according to Martinez.
“We want those with very high viral loads out of the system and to isolate; those that only have small amounts of remnants are not as relevant in terms of public health,” Martinez said.
Video by Matthew Bornhorst
Cost Efficiency for the University
As the professors dove deeper into establishing ways to test the entire campus weekly, more members joined the team. There were roughly six members that all had experience in different fields, such as molecular biology, robotics and coding.
One main contributor to cost efficiency was the decision to pool samples. Instead of testing every individual sample, the team pools five samples in one group to test together. If a group tests positive for COVID-19, the team will then go back and test the individual samples to see who actually has the virus.
The test is only used for asymptomatic students, faculty and staff, so the frequency of positive tests is relatively low, making this pooling process highly efficient.
With this tactic, they are able to test 800 samples a day instead of 4,000 samples a day, saving time and money.
Back On Campus
Come September and October, students were invited to return to campus. Freshmen moved into their respective dorms and some classes continued in-person instruction while the majority of classes resumed an online format.
During these months, the team came to the conclusion that each test would cost less than one dollar to run. They began validating their test against the one that was being used at the campus health center. The health center has been implementing a test that is approved by the FDA which makes the validation of the saliva test highly reliable.
Collecting saliva for samples is more convenient than using the nasal swab. There is no way to miscollect a sample unless someone misses the tube, Martinez said.
The nasal swab is the most effective way to test for COVID-19, but it’s easy to do it wrong, Martinez said. The test requires a skilled professional and is uncomfortable for the patient. The collection in which the patient swabs only the front of their own nose, the test currently in use at Cal Poly, is less reliable. With a self-conducted collection such as this one, it’s possible that individuals will not collect the cells needed to show if they actually have COVID-19 or not.
To check to see if the saliva test was accurate, the team ran their results against the swabs conducted at the health center. By November and December, they knew that their saliva test worked.
“We had a really good sensitive test on our hands with the saliva test,” Martinez said.
Cal Poly’s Very Own
The process of running internal validations from collection to results means that a majority of the procedures happen outside of the lab. It takes five to 10 people per task. Some of those tasks include collection, transportation, identification, placement on corresponding racks and the scanning of each sample. The members of the team stressed that they depend on strict organization.
There are currently 17 undergraduate students employed at the lab and more are expected to be hired as they continue. Students working within the lab are asked to spend a minimum of 10 hours per week conducting research. One student involved within the lab is a biology sophomore concentrating in cellular and molecular biology. Aside from her crowded schedule, Kae Nurge is very thankful to be a part of this effort.
“I got an email from VanderKelen that said she heard I was interested in the lab and she asked if I would be willing, I have no idea who said I was willing, still to this day I have no idea,” Nurge said. “But that’s what’s so amazing, I’m very grateful for this opportunity that fell on my lap.”
What Comes Next
Saliva testing is intended to be a faster experience. Without the obligation to monitor one-on-one collection as was needed with the nasal swab, students will form rows and spit into a tube once they reach their place in line.
Bubbling beneath the surface the researchers are considering the “what ifs” in the future. Some of the big questions they face include: what populations of viruses are present at Cal Poly, and are they changing? In addition, they are looking to develop testing for antibodies.
“We don’t want to find ourselves in the position that we were in during March,” Martinez said. “We have learned a great lesson, we have to keep our finger on the pulse a little more as to what might surprise us.”
Martinez expressed great appreciation for the Cal Poly administration including an aside to President Jeffrey Armstrong. Armstrong insisted that the students and faculty involved deserve all the credit.
“I am very proud of the work done by Dr. Martinez,” President Armstrong said. “[He] is awesome and represents the best of the teacher-scholar model and thus empowers learn by doing for students.”