Washington University’s saliva test for Covid-19 faster and easier


RESEARCHERS at the Washington University School of Medicine in St. Louis have developed a new saliva test to detect the SARS-CoV-2 virus faster and easier. The results from this diagnostic test are available in a few hours, and therefore easily communicated to people who were tested within the day. The test does not require special swabs or reagents that may be in short supply because it is highly sensitive to detecting even tiny levels of virus in a saliva sample.

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 in collaboration with the biotechnology company Fluidigm. The test could help simplify and expand the availability of COVID-19 diagnostic testing across broad populations. This test does not rely on the extraction of viral RNA to detect the virus, which his a time-consuming and expensive process. It 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.

The test allows individuals to collect saliva samples themselves by spitting into a small test tube, eliminating the need for healthcare workers to insert long nasal swabs deep into the nasal cavity. This allows the rapid testing of large numbers of people. The researchers have verified the saliva test against the standard nasal swab tests and found that the new test results aligned with the standard test results — whether positive or negative — in all cases.