A new saliva test to detect the SARS-CoV-2 virus has been developed by researchers at Washington University School of Medicine in St. Louis. Results from the COVID-19 diagnostic test are available in a few hours and, ideally, able to be communicated to people tested within a day. Highly sensitive to detecting even tiny levels of the virus in a saliva sample, the test does not require special swabs and reagents that have been in short supply.
Developed in collaboration with the biotechnology company Fluidigm, the test could help simplify and expand the availability of COVID-19 diagnostic testing across broad populations. Such testing does not rely on the extraction of viral RNA to detect the virus – a time-consuming and expensive process – and could be scaled up easily, in part because people can collect their own saliva samples, relieving health-care workers of the need to conduct sample collection as they do for nasal and throat swab tests.
On Aug. 25, Fluidigm received emergency use authorization (EUA) from the Food and Drug Administration as the manufacturer of the test. This authorization allows the university to perform the test. Washington University filed a separate EUA application with the FDA that is still pending.
The saliva test was developed by a large, highly skilled team from the Department of Genetics and the McDonnell Genome Institute, both at Washington University School of Medicine.
“This is a significant advance in COVID-19 testing that is a simpler, faster and more economical test that can greatly expand our ability to detect the level of COVID-19 infection within the community via large-scale population screening for the SARS-CoV-2 virus,” said Jeffrey Milbrandt, MD, PhD, the James S. McDonnell Professor and head of the Department of Genetics and the McDonnell Genome Institute.
According to the researchers, the test will allow for rapid testing of large numbers of people, which is essential for a safe return to work or school as economies strive to open up. Supporting its mission of education and research, Washington University’s faculty, staff and students could return to campus and potentially be screened to monitor levels of the virus in the community and stop it from spreading. The ability to scale up the number of tests that can be conducted also has the potential to help St. Louis city and county as well as the state of Missouri and regional businesses reopen safely. The saliva tests also could be given periodically to residents of nursing home and retirement communities, who are more vulnerable to infection because of age. Those who test positive could be quickly identified and quarantined.
“People can collect the sample themselves, and it doesn’t require an uncomfortable nasal swab,” Milbrandt said. “Another problem with current testing is the shortage of certain lab supplies that are required to process viral samples. We have developed a method to process the saliva samples that doesn’t require these specialized supplies.”