We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us

Download Mobile App

Rapid Olfactory Test Shows Potential as Screening Tool for COVID-19

By LabMedica International staff writers
Posted on 20 Jul 2021
Print article
A study that evaluated the feasibility of a novel, objective olfactory test as part of an initial screening for COVID-19 in adults with unknown disease status has concluded that olfactory dysfunction (OD) is one of the earliest and strongest predictors of COVID-19 infection, and thus is promising as a disease screening tool.

In the prospective, cross-sectional study, researchers at University of California, San Diego (La Jolla, CA, USA) enrolled healthy adults (aged ≥ 18 years) from a single college campus COVID-19 screening site. Participants were screened for OD using a novel scent card (SAFER Diagnostics) followed immediately by polymerase chain reaction (PCR) testing for SARS-CoV-2 from nasopharyngeal swabs. The SAFER card contained a single scent in a scratch-and-sniff label that the participant identified from 8 answer options: lemon, grape, floral, blueberry, banana, mint, unsure, or no scent. Answers were processed electronically via a QR code. An incorrect choice was classified as OD. Participant demographics, medical history, COVID-19 symptoms, and subjective smell function on a binary and 10-point visual analog scale (VAS, with 0 indicating no sense of smell and 10 indicating normal sense of smell) were also collected.

A total of 163 participants were prospectively screened for OD using the scent card followed by SARS-CoV-2 PCR testing. Of those who tested PCR-positive for COVID-19, 75% (12 out of 16) failed olfactory screening compared with 4.8% (7 out of 147) among those testing PCR-negative for COVID-19. The sensitivity, specificity, positive predictive value, and negative predictive value of the scent card in detecting those with COVID-19 were 75.0%, 95.2%, 63.2%, and 97.2%, respectively. Including the symptom fatigue along with OD achieved 93.8% sensitivity and 89.8% specificity in disease screening. The addition of fever and cough did not further increase sensitivity.

While only 37.5% (6 out of 16) of COVID-19 test-positive participants reported subjective anosmia, 75% failed screening with the scent card. A failed scent card screen was the greatest predictor of COVID-19 positivity (odds ratio [OR], 80.24; 95% CI, 14.77-435.90) when compared with other symptoms including cough, fever, fatigue, and a history of COVID-19 exposure. Thus, the study demonstrated that a rapid psychophysical olfaction test is feasible as a screening tool for COVID-19.

Related Links:
University of California, San Diego

Gold Supplier
SARS-CoV-2 Antigen Rapid Test
RapiSafe SARS-CoV-2 Antigen Rapid Test (Professional use)
Silver Supplier
Glass Beaker
Globe Glass Beakers, Griffin Style
Glucose & Lactate Measuremen Device
Multiplex Molecular Panel

Print article


Molecular Diagnostics

view channel
Image: New chip could make treating metastatic cancer easier and faster (Photo courtesy of Georgia Institute of Technology)

Simple Blood Test Detection Method Could Revolutionize Cancer Treatment

Cancer spreads via circulating tumor cells (CTCs) that travel through the blood to other organs, and they are nearly impossible to track. When a tumor starts metastasizing, it sheds its cell into the blood.... Read more
Copyright © 2000-2022 Globetech Media. All rights reserved.