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Published on: September 13, 2024
COVID-19 Viral Load in the Severity of and Recovery From Olfactory and Gustatory Dysfunction
Ryan H W Cho1, Zion W H To1, Zenon W C Yeung1
1Department of Otorhinolaryngology-Head and Neck Surgery, United Christian Hospital and Tseung Kwan O Hospital, Hong Kong.
Objectives/Hypothesis:
This study investigated olfactory and gustatory dysfunction in the 2020 novel coronavirus disease (COVID-19) patients, and their correlations with viral load evaluation.
Study Design:
Prospective cross-sectional cohort study.
Methods:
One hundred forty-three symptomatic patients being screened for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were invited to participate. The clinical data of 83 confirmed COVID-19 subjects were collected, with 60 patients who were symptomatic but negative for COVID-19 recruited as controls. The prevalence and severity of and recovery time for olfactory and gustatory dysfunction, and cycle threshold (Ct) values from a SARS-CoV-2 polymerase chain reaction assay of nasopharyngeal and deep throat swabs were collected. Their correlations with Ct values were reported.
Results:
Thirty-nine (47.0%) and 36 (43.4%) COVID-19 patients reported olfactory and gustatory dysfunction, respectively. The results of one-way analysis of variance did not show statistically significant relationships between the Ct values and severity of olfactory and gustatory dysfunction (P = .780 and P = .121, respectively). Among the COVID-19 patients who reported smell and taste loss, 28/39 (71.8%) and 30/36 (83.3%) experienced complete recovery, respectively. The mean recovery time was 10.3 ± 8.1 days for olfactory dysfunction and 9.5 ± 6.8 days for gustatory dysfunction. The recovery time was not correlated with the Ct values (Pearson correlation coefficient, smell: -0.008, P = .968; taste: -0.015, P = .940).
Conclusions:
There is a high prevalence of olfactory and gustatory dysfunction in COVID-19. However, the severity of and recovery from these symptoms have no correlations with the viral load of SARS-CoV-2.
Level Of Evidence:
4 Laryngoscope, 130:2680-2685, 2020.
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