An breakthrough new COVID-19 saliva test, named SalivaDirect, received emergency use approval from the US Food and Drug Administration, potentially opening the door to broader testing. 

The new FDA-approved test, developed by researchers from the Yale School of Public Health, is about as sensitive as a traditional COVID-19 test, but is less invasive to perform, easier to store, and compatible with a variety of platforms. It could also be priced as low as $10 per test. 

FDA Commissioner Stephen M. Hahn called the test “groundbreaking” in a press release.

“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,” he said. 

To collect a test sample, people are asked to think about a favorite food or upcoming meal to generate saliva, then simply spit into a sterile tube. The process is much less invasive than a traditional COVID-19 test, which requires trained professionals to stick swabs far up the nose and down the throat to collect samples.  

And unlike previously approved COVID-19 saliva tests, the samples for this test don’t need to be refrigerated, nor do they require many reagents. This cuts down the cost of the materials needed for the test to under US $5 per test. 

“We simplified the test so that it only costs a couple of dollars for reagents, and we expect that labs will only charge about $10 per sample,” said Nathan Grubaugh, whose lab developed the Yale test. “If cheap alternatives like SalivaDirect can be implemented across the country, we may finally get a handle on this pandemic, even before a vaccine.” 

From The National Basketball Association To The FDA

Yale’s breakthrough saliva diagnostic was tested first on samples from an unusual cohort of people – players in the US National Basketball Association (NBA).

NBA players had previously been using a saliva test developed by Rutgers University that cost anywhere from US $60 to $150 per test. However, in a trial sponsored by the NBA and the National Basketball Players Association, the Yale test yielded similarly accurate results for less than a fifth of the price. 

The Yale test circumvents one key step that other tests on the market take – it doesn’t use expensive reagents to stabilize the sample and extract the virus’ genetic material. Instead, the Yale test relies on cheaper reagents and a heating step to separate the virus’ genetic material from the rest of the sample. While this causes the test to be slightly less sensitive, it makes the test much cheaper than most widely used alternatives. 

And while the test has been used so far in NBA players, the Yale researchers hope it can quickly be adapted for broader use. Grubaugh and his co-authors have said they do not wish to commercialize the test. 

The test works with a variety of commonly available reagents and platforms, and the protocol for running the test has been made publicly available.  

Image Credits: Flickr: Penn State Health, Flickr: Prachatai.