Good news for anyone who isn’t a fan of the dreaded COVID-19 nasal swab: The Food and Drug Administration gave emergency approval to a “groundbreaking” COVID-19 saliva test out of Yale University on Aug. 15.
“Providing this type of flexibility for processing saliva samples to test for COVID-19 infection is groundbreaking in terms of efficiency and avoiding shortages of crucial test components like reagents,” said FDA Commissioner Stephen M. Hahn, M.D., in a news release.
In its own news release, Yale University said the test, SalivaDirect, is “simpler, less expensive, and less invasive” than the nasal swab test, yet it yields similar results.
“This is a huge step forward to make testing more accessible,” said Chantal Vogels, a Yale postdoctoral fellow and co-leader of the laboratory development and validation. “This started off as an idea in our lab soon after we found saliva to be a promising sample type of the detection of SARS-CoV-2, and now it has the potential to be used on a large scale to help protect public health. We are delighted to make this contribution to the fight against coronavirus.”
Although SalivaDirect is not the first saliva-based test approved by the FDA, the Yale researchers improved the saliva test method—making it less costly and easier to produce. So far, the Yale staff has only used it to test NBA players and staff, but that can change now that the FDA has signed off on it.
Yale said it doesn’t plan to commercialize the test. Instead, the university will partner with Jackson Laboratory for Genomic Medicine to examine how to scale production to provide tests across the country. Yale believes labs will only charge around $10 per sample.
“Wide-spread testing is critical for our control efforts,” Yale assistant professor Nathan Grubaugh said. “If cheap alternatives like SalivaDirect can be implemented across the country, we may finally get a handle on this pandemic, even before a vaccine.”
The FDA said SalivaDirect “enhances the capacity for increased testing” because it doesn’t need additional components—like expensive saliva collection tubes. Because the test does not rely on any “proprietary equipment from Yale,” it can be assembled and used in labs throughout the country.
Grubaugh explained to NPR that the test uniquely does not require a separate nucleic acid extraction step. The FDA said that’s significant because it eliminates the need for extraction kits that were also prone to shortages.
“We get rid of the most cumbersome stuff, which is extracting the nucleic acids,” Grubaugh said. “And we replace that with something that’s really simple. You add an enzyme, you heat it up, so you lose the most expensive step and the most time consuming and the most skilled.”
The test doesn’t just alleviate the discomfort often associated with the nasal swab tests—it also poses less risk to healthcare workers because the sample is self-collected by patients.
The FDA said that this is the fifth COVID-19 saliva test that it has approved. The administration originally approved the first saliva-based diagnostic test on April 13.
NPR reported another saliva test, called Shield T3, is administered to students two times a week at the University of Illinois at Urbana-Champaign. Martin Burke, the chemistry professor who helped design that test, said it provides results in three to six hours. Like SalivaDirect, the university plans to expand Shield T3 nationally.
“So fast and frequent—that’s absolutely the key,” Burke said. “You know, if you don’t get your results back for one or two days, beyond that, it’s pretty much useless in terms of being able to mitigate the spread.”