Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms

Gerkin, Richard C., Ohla, Kathrin, Veldhuizen, Maria G., Joseph, Paule V., Kelly, Christine E., Bakke, Alyssa J., Steele, Kimberley E., Farruggia, Michael C., Pellegrino, Robert, Pepino, Marta Y., Bouysset, Cédric, Soler, Graciela M., Pereda-Loth, Veronica, Dibattista, Michele, Cooper, Keiland W., Croijmans, Ilja, Di Pizio, Antonella, Ozdener, M. Hakan, Fjaeldstad, Alexander W., Lin, Cailu, Sandell, Mari A., Singh, Preet B., Brindha, V. Evelyn, Olsson, Shannon B., Saraiva, Luis R., Ahuja, Gaurav, Alwashahi, Mohammed K., Bhutani, Surabhi, D'Errico, Anna, Fornazieri, Marco A., Golebiowski, Jérôme, Hwang, Liang-Dar, Öztürk, Lina, Roura, Eugeni, Spinelli, Sara, Whitcroft, Katherine L., Faraji, Farhoud, Fischmeister, Florian Ph. S., Heinbockel, Thomas, Hsieh, Julien W., Huart, Caroline, Konstantinidis, Iordanis, Menini, Anna, Morini, Gabriella, Olofsson, Jonas K., Philpott, Carl M. ORCID:, Pierron, Denis, Voznessenskaya, Vera V. and Albayay, Javier and GCCR Group Author (2021) Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms. Chemical Senses, 46. ISSN 0379-864X

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In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.

Item Type: Article
Additional Information: © The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail:
Uncontrolled Keywords: anosmia,chemosensory,coronavirus,hyposmia,olfactory,prediction,physiology,sensory systems,physiology (medical),behavioral neuroscience ,/dk/atira/pure/subjectarea/asjc/1300/1314
Faculty \ School: Faculty of Medicine and Health Sciences > Norwich Medical School
UEA Research Groups: Faculty of Medicine and Health Sciences > Research Centres > Lifespan Health
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Depositing User: LivePure Connector
Date Deposited: 09 Jan 2021 01:21
Last Modified: 19 Oct 2023 02:52
DOI: 10.1093/chemse/bjaa081

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