LSU Researchers Develop Saliva-based Test to Make COVID-19 Easier to Track
The new saliva-based test only requires spitting into a tube, avoiding the discomfort of nasopharyngeal swabs deep inside the nose.
Saliva-based tests will make it easier to track COVID-19 and monitor the spread of the virus—especially in large populations, such as in schools. The new test was developed by LSU Professors Stephania Cormier and Rebecca Christofferson (a respiratory immunologist with a joint position as the Wiener Chair Professor in the LSU Department of Biological Sciences and the LSU Pennington Biomedical Research Center, and an emerging viruses expert in the LSU School of Veterinary Medicine’s Department of Pathobiological Sciences).
August 6, 2020 Update: This is a pilot program to add to the growing data from LSU researchers and other scientists about how saliva-based testing can be used for COVID-19 surveillance. In terms of accessibility to this type of testing, LSU is showing utility, not mass availability at this time.
BATON ROUGE, August 3, 2020 — LSU Professors Stephania Cormier, a respiratory immunologist, and Rebecca Christofferson,
an emerging viruses expert, have developed a saliva-based test to help track COVID-19
in K-12 school children and teachers in Baton Rouge, Louisiana. This initiative was
recently mentioned at congressional hearings in Washington, D.C. where Assistant Secretary
for Health at the Department of Health and Human Services Admiral Brett Giroir, MD
testified that such programs are part of the robust surveillance system needed to
track COVID-19.
Last spring, Cormier and Christofferson set up the River Road Testing Lab at the LSU
School of Veterinary Medicine to help take some of the testing burden off of local
hospitals and help the state overcome many hurdles, including supply chain issues
and turnaround times for test results, which have been common challenges nation-wide.
Realizing how the discomfort of nasopharyngeal swabs deep inside the nose may prevent
some people from seeking out, agreeing to, and/or repeating testing, Cormier began
thinking of saliva as an alternative source for samples. Researchers across the country
had begun preliminary investigations into saliva as an alternative, with several studies
showing comparable test results for saliva and nasopharyngeal swabs.
“We found saliva-based tests to be as accurate as nasopharyngeal swabs.”—Rebecca Christofferson
“This is especially important for repeated testing for surveillance or research because
it could decrease the number of people who drop out of a study,” Christofferson said.
Nasopharyngeal swabs deep into the nasal cavity are considered the gold standard for
many respiratory disease tests. Rarely, however, have they been used on the scale
required to continuously test broad populations for something like COVID-19. When
the current pandemic started, most established and federally approved testing methods
in hospitals, clinics, and labs relied on nasopharyngeal swabs, which, other than
the discomfort, come with a few additional caveats—the tests should be administered
by healthcare professionals, require a viral or universal transport medium (VTM or
UTM) for storage and transport, and frequently make subjects sneeze or cough, which
is one of the reasons healthcare workers need to wear full protective gear to take
samples. Saliva-based tests, meanwhile, come with less disadvantages.
For the LSU team, development of the saliva-based test—with most of the work happening
at Pennington Biomedical Research Center (PBRC)—involved not only optimizing the assay,
or lab-based process, but also putting together an emergency use authorization and
submitting it to the U.S. Food and Drug Administration, or FDA. As part of this, the
researchers also had to validate their test and show that the results they were getting
with saliva were qualitatively equal to using nasopharyngeal swabs.
“We found saliva-based tests to be as accurate as nasopharyngeal swabs,” Christofferson
said. “A positive result with a nasopharyngeal swab meant a positive result with saliva,
and so on.”
One of the biggest challenges in switching from nasopharyngeal swabs to saliva-based
testing will involve a public education component.
“Snot,” Christofferson said. “Snot is not saliva. We don’t want people to just clear
their sinuses and give us what’s in there. We basically need you to drool into a tube—no
snot. Also, bits of food in the sample is less than ideal.”
“The mucus or snot interferes with the assay,” Cormier explained. “It took a lot of
back and forth with the protocol to get the samples we needed, but we did it.”
Elsa Hahne
LSU Office of Research & Economic Development
ehahne@lsu.edu
PBRC media contact Ted Griggs
Pennington Biomedical Research Center
ted.griggs@pbrc.edu
LSU media contact Ernie Ballard
LSU Media Relations
225-578-5685
eballa1@lsu.edu