Easier-to-use virus saliva tests start to catch on
As the coronavirus pandemic broke out across the country, health care providers and scientists relied on the standard method for detecting respiratory viruses: sticking a long swab deep into the nose to get a sample. The obstacles to implementing such testing on a mass scale quickly became clear.
Among them: Many people were wary of the unpleasant procedure, called a nasopharyngeal swab. It can be performed only by trained health workers, putting them at risk of infection and adding costs. And the swabs and chemicals needed to test for the virus almost immediately were in short supply.
Some places, like Los Angeles County, moved early to self- collected oral swabs of saliva and sputum, with the process supervised at drive-thru testing sites by trained personnel swathed in protective gear. Meanwhile, researchers began investigating other cheaper, simpler alternatives to the tried-and-true approach — including dribbling saliva into a test tube.
But the transition has not been immediate. Regulators and scientists are generally cautious about new, unproven technologies and have an understandable bias toward wellestablished protocols.
“Saliva is not a traditional diagnostic f luid,” said Yale microbiologist Anne Wyllie, part of a team whose saliva- based test, called SalivaDirect, received emergency use authorization from the Food and Drug Administration in August. “When we were hit by a virus that came out of nowhere, we had to respond with the tools that were available.”
Eight months into the pandemic, the move toward saliva screening is gaining traction, with tens of thousands of people across the country undergoing such testing daily. However, saliva tests still represented only a small percentage of the more than 900,000 tests conducted daily on average at the end of September.
Yale is providing its protocol on an open-source basis and recently designated laboratories in Minnesota, Florida and New York as capable of performing the test. Besides the Yale test, the FDA has authorized emergency use of several others, including versions developed at Rutgers University, the University of Illinois at Urbana- Champaign, the University of South Carolina and SUNY Upstate Medical University. A further advance, an athome saliva test, could be headed for FDA authorization, too.
Since the start of the pandemic, the Trump administration’s approach to testing has been hampered by missteps and controversy. As a key health agency during an unprecedented emergency, the FDA’s effectiveness relies on public trust in how it balances the need for speed in authorizing innovative products, like saliva tests and vaccines, with ensuring safety and effectiveness, said Ann Keller, an associate professor of health policy at the University of CaliforniaBerkeley.