Researchers investigate an at-home 'scratch-and-sniff' test for COVID-19

Sara LaJeunesse
December 22, 2020

UNIVERSITY PARK, Pa. — A self-administered "scratch-and-sniff" test for COVID-19 may be around the corner, according to researchers at Penn State, the University of Florida and Arizona State University. The team, which received $912,000 from the National Institutes of Health, will analyze two different smell tests with a goal of developing inexpensive, at-home tests to help identify new cases of COVID-19 and provide a warning sign of a community outbreak in time to thwart it.

“In 2020 alone, COVID-19 cost a million lives worldwide,” said John Hayes, professor of food science at Penn State and a principal investigator of the study. “It is critical that we develop new tools that can mitigate the spread of the deadly SARS-CoV-2 virus. Unfortunately, definitive SARS-CoV-2 testing has proven difficult to implement in many countries, including the United States, due to technical, financial and governmental hurdles to universal access and timely processing. Symptom-based screening offers a valuable, albeit imperfect, complement to viral testing that can help identify many individuals with the disease for isolation as well as for treatment.”

The researchers will evaluate the results of two self-administered, scratch-and-sniff smell tests. The first involves asking users to identify odors such as smoke, strawberry, chocolate and onions, while the second is designed to reveal a participant’s sensitivity to different concentrations of the same odor.

“One thing that’s become very apparent with COVID-19 is that there’s no single symptom that is universal for everyone who has the disease, but one of the most common is smell loss, especially early, sudden smell loss,” said Steven Munger, director of the University of Florida's Center for Smell and Taste and lead principal investigator of the study. “There are a growing number of studies that suggest 50% to 70% of individuals with COVID-19, even if they don’t have another symptom, are experiencing smell loss.”

The two-year project, funded by the Coronavirus Aid, Relief and Economic Security (CARES) Act and the NIH’s RADx-rad program, includes participants who are COVID-positive and COVID-negative from diverse racial and ethnic backgrounds and who live in the communities surrounding the University of Florida, Penn State and Arizona State. Participants will be asked to use the two different smell tests to determine which is a better predictor of a COVID diagnosis.

Separately, the investigators also will recruit participants in residential and workplace communities in those same areas to take a smell test weekly over six weeks to track how many become COVID-positive in an effort to predict COVID emergence in a community.

“If you suddenly see an increase in smell loss in a dormitory, for example, that could be an early warning sign of community spread,” said Munger.

Cara Exten, assistant professor of nursing at Penn State and a co-investigator on the project, added that olfactory testing could provide a leading indicator for the emergence of COVID-19 “hot spots.”

“Identifying where COVID-19 outbreaks are occurring, in real time, is essential for authorities to make public health decisions and for private actors to develop targeted safety strategies,” said Exten. “For example, until local outbreaks can be identified rapidly, many teachers and parents may not feel safe bringing children into a school environment, many businesses may not be able to safely re-open, and individuals will be unable to gauge the personal risks associated with travel or simply going to work.”

As part of the NIH RADx-rad program, the team will share study data weekly with an NIH-funded Data Coordination Center using automated computational tools developed by principal investigator Richard Gerkin, a data scientist at Arizona State University. By analyzing data continuously, the team can increase the speed at which its findings can be applied in the fight against COVID-19.

“We really needed a team science approach here, given all the various moving parts,” said Hayes. “By having a behavioral scientist, a biologist, an epidemiologist and a data modeler all bringing our respective expertise to bear, we can tackle this urgent problem.” 

According to the team, the next step after the study concludes could be to seek approval from the U.S. Food and Drug Administration to use a smell test to formally diagnose COVID-19. Such a test could provide another weapon in the fight against the coronavirus.

“Even though vaccines seem to be on the horizon and COVID testing is becoming more accessible in a variety of environments, there are still plenty of people who have a hard time getting tested or being tested regularly enough to adequately screen for COVID-19,” said Munger. “Augmenting that type of testing with smell testing could provide an inexpensive and distanced way of identifying people who have acquired COVID-19 and helping them to get treatment or isolation early on.”

(Media Contacts)

Last Updated December 22, 2020