The smell test

The smell test

Something as simple as a 50-cent scratch-and-sniff could hold the keys to stemming the spread of the coronavirus at a fraction of the cost and time of high-tech tests, new CU Boulder research suggests.

“A lot of people have joked about this idea, but this is the first effort to ask in a rigorous, mathematical way: Could screening for loss of smell actually work?” author Roy Parker, a professor of biochemistry at CU said. “We were surprised by how good the results were.”

For the study, Parker and Dan Larremore, an assistant professor of computer science, teamed up with CU alumnus Derek Toomre, a professor at the Yale School of Medicine who has developed a call phone app test that assesses sense of smell.

Studies show that, when simply asked about their symptoms, only about half of people with COVID-19 report loss of smell, aka anosmia. But when given a standardized test, that number rises to eight in 10, even among people with no other symptoms.

That’s far more prevalent than fever, which impacts fewer than one in four people with the virus. Anosmia also lasts longer, affecting patients for a week or more while fever may only last a day or two. In addition, while fever is associated with many diseases, loss of smell without a stuffy nose is highly specific to COVID.

The team used modeling to predict the effect of smell-testing in several hypothetical scenarios, including: on a college campus where individuals were tested once a week, every three days or daily; and at a one-day event where it was used for point-of-entry screening.

In each case, the sniff-test served not as a definitive diagnostic test, but as a screening tool. Those who failed would then be referred for a gold-standard PCR or a rapid antigen test. In general, it was found that scratch-and-sniffs every three days worked better than weekly PCR tests in curbing infection at a tiny fraction of the price.

“We found that you could reduce risk inside by 75 percent if you tested everybody, and it would only cost about 50 cents each,” Parker said.

Although the test is not commercially available yet, the team has applied for Emergency Use Authorization from the FDA. If approved, they could swiftly ramp up production to hundreds of millions of tests per week.

The findings have not yet been published in a peer-reviewed journal, and the authors caution that more research is necessary, but they are optimistic. “This is not a silver bullet,” said Larremore. “But it could be another useful tool in our repertoire."

Top Stories

Weathering COVID
01/14/2021
Weathering COVID
By Missy Votel

With homeless plight worsened by pandemic, winter survival kits come to rescue

Read More
Taking a new route
01/14/2021
Taking a new route
By Max Owens

Ouray Ice Fest comes out of the gorge and onto the screen for 2021

Read More
Sharper focus
01/14/2021
Sharper focus
By by Andrea Dukakis / Colorado Public Radio

State clarifies vaccine plan, proposes moving ages 65-69 up ladder

Read More
The world of Phil
12/31/2020
The world of Phil
By Missy Votel

Friends, family remember the life and times of a reluctant legend
 

Read More
Read All in Top Stories

The Pole

Last dance
01/14/2021

The Sundance Kid is riding off into the sunset. Last month, Robert Redford announced he is selling his Sundance resort, north of Provo, Utah. The resort, which Redford founded more than 50 years ago, is being bought by real estate investment firms Broadreach Capital Partners and Cedar Capital Partners.

Gotta get up to get down
01/07/2021
The Bluebird has landed. Colorado’s first “backcountry-only” ski area fired up the, uh, skin tracks Dec. 31, 2020. Located on Bear Mountain, along the Continental Divide between Kremmling and Steamboat, the idea was the brainchild of ski buddies Erik Lambert and Jeff Woodward. The idea behind Bluebird is a ski area that caters to pretty much everyone, provided they don’t mind slogging for their turns.
The smell test
12/31/2020

Something as simple as a 50-cent scratch-and-sniff could hold the keys to stemming the spread of the coronavirus at a fraction of the cost and time of high-tech tests, new CU Boulder research suggests.

Sorry, folks
12/10/2020

A ride or hike might seem like a good idea during the current nonwinter. But before you head out, be forewarned that even though it feels like summer, winter wildlife closures went into effect Dec. 1 on some Durango outdoor playgrounds. The closures, which remain in place through April 15 to protect wintering deer and elk, include:

Read All Stories in the Pole