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COVID-19-Associated Chemosensory Loss Continues to Decline
Evan R Reiter1, Daniel H Coelho1, Evan French1
1Department of Otolaryngology-Head and Neck Surgery, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA.
Summary
Smell and taste loss, once a key COVID-19 symptom, is now less common with newer variants. This suggests these sensory changes may no longer reliably diagnose COVID-19 infection.
Area of Science:
- Infectious Diseases
- Neurology
- Otolaryngology
Background:
- Chemosensory disturbances, including smell and taste loss, were recognized as hallmark symptoms of COVID-19.
- Emerging evidence indicates a shift in the clinical presentation of COVID-19, with a declining frequency of olfactory dysfunction.
Purpose of the Study:
- To investigate the changing prevalence of smell and taste loss in relation to COVID-19 variants.
- To determine if chemosensory disturbances retain diagnostic value for COVID-19 in the era of Omicron variants.
Main Methods:
- Utilized the National COVID Cohort Collaborative database to identify patients diagnosed with COVID-19.
- Analyzed patient data for the presence of smell and taste loss within two weeks of diagnosis.
- Correlated symptom incidence with variant peak prevalence periods obtained from Covariants.org.
Main Results:
- Established a baseline for chemosensory loss rates during the "Untyped" variant period (April-June 2020).
- Calculated odds ratios for smell or taste disturbance, showing a significant decrease with Alpha, Delta, and Omicron (K, L, C, B) variants.
- Observed substantially lower odds ratios for Omicron subvariants compared to the baseline.
Conclusions:
- The declining incidence of smell and taste disturbances with recent COVID-19 variants, particularly Omicron, diminishes their predictive value.
- Smell and taste changes may no longer be a reliable indicator for diagnosing COVID-19 infection.
- Future diagnostic strategies should consider the evolving symptom profile of SARS-CoV-2 infections.
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