Prevalence of taste and smell dysfunction in mild and asymptomatic COVID-19 patients during Omicron prevalent period in Shanghai, China: a cross-sectional survey study

Abstract

ObjectivesCOVID-19, which is caused by SARS-CoV-2, is a severe threat to human health and the economy globally. This study aimed to investigate the prevalence of taste and/or smell dysfunction and associated risk factors in mild and asymptomatic patients with Omicron infection in Shanghai, China.DesignThis was a questionnaire-based cross-sectional study.SettingCOVID-19 patients at the makeshift hospital in the Shanghai World Expo Exhibition and Convention Centre were recruited from March to April 2022.ParticipantsIn total, 686 COVID-19-infected patients who were defined as mild or asymptomatic cases according to the diagnostic criteria of New Coronavirus Pneumonia Prevention and Control Programme ninth edition (National Health Commission of China, 2022) were enrolled.MeasuresData to investigate taste and smell loss and to characterise other symptoms were collected by the modified Chemotherapy-induced Taste Alteration Scale and Sino-Nasal Outcome Test-22 questionnaires. The risk factors for the severity of taste/smell dysfunction were analysed by binary logistic regression models.Results379 males (379/686, 55.2%) and 307 females (307/686, 44.8%) completed the questionnaires to record recent changes in taste and smell ability. A total of 302 patients (44%) had chemosensory dysfunction with Omicron infection, of which 22.7% (156/686) suffered from both taste and smell dysfunction. In addition, cough (60.2%), expectoration (40.5%), fever (33.2%) and sore throat (32.5%) were common symptoms during Omicron infection. The quality-of-life-related indicators were negatively associated with participants’ self-reported taste and smell dysfunction.ConclusionsThe prevalence of taste or/and smell dysfunction in patients with Omicron infections was 44%. Individuals with chemosensory dysfunction had significantly higher rates of various upper respiratory influenza-like symptoms, xerostomia and bad breath. Moreover, smell dysfunction was a risk factor for the prevalence of taste dysfunction in patients with Omicron infection.Trial registration numberChiCTR 2200059097.

Impacts of COVID-19 on Food Choices and Eating Behavior among New Zealand University Students

“…Approximately 25% of the participants reported sensory change, and only around 5% reported complete loss of taste or smell, compared to the 40–60% experiencing smell or taste changes in a meta-analysis of studies based on objective measures [ 4 ]. However, this finding is consistent with more recent evaluations of smell and taste loss in COVID-19 patients [ 55 , 56 ], with evidence suggesting that the occurrence of smell and taste changes has decreased in more recent variants of COVID-19 [ 57 ]. For example, an analysis of 12 reports of patients infected with COVID-19 during the Omicron wave had a pooled estimated olfactory dysfunction of only 13% [ 14 ].…”

A Review on the Epidemiology and Mechanism of Actions of Olfactory Dysfunction as a Sequela of SARS-CoV-2 Infection

“…However, increased co-morbidities and prescription drugs in elderly individuals could additionally impact the clinical course of OD [69,70]. Additionally, fever, cough, expectoration, stuffy nose, nasal congestion, purulent nasal, sore throat, foul breath, and xerostomia (oral dryness) are typical symptoms observed in patients with OD and patients who have suffered from three or more upper respiratory symptoms were prone to experience OD [71].…”

“…Based on the findings of multivariate analysis, risk factors associated with reporting a loss of smell were younger age [67,68], asthma [72], emphysema [73], female sex [29,[46][47][48][49], or cough [49,71,74]. A clinical risk category approach by Johnson et al (2022) [72], revealed the high-risk patients and individuals who were most likely to get serious infections and poor clinical outcomes.…”

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“…About 1 in 5 people with COVID-19 report persistent (i.e., lasting more than 10 days) COVID-19-related anosmia (loss of the sense of smell), hyposmia (reduced sense of smell) or parosmia (distorted sense of smell; e.g., Chary et al, 2020 ; Chiesa-Estomba et al, 2020 ; Antolín-Amérigo et al, 2021 ; Printza et al, 2021 ). A similar proportion of people with COVID-19 report ageusia (loss of the sense of taste), hypogeusia (reduced sense of taste) or dysgeusia (altered perception of taste), with many people reporting both smell and taste impairment ( Wang et al, 2023 ). Even though the prevalence of COVID-19-associated smell and taste impairment decreased with later variants of the virus ( Boscolo-Rizzo et al, 2022 ), it still appears significant for the Omicron variant at around 12% in people with European ancestry ( von Bartheld and Wang, 2023 ).…”