90% of patients contaminated by COVID-19 Have Lost Their Sense Of Smell
An European study led by a French research team at Hopital Foch in Paris (Suresnes) has concluded that nearly 90% of contaminated patients by coronavirus have lost their sense of smell.
Patients with laboratory-confirmed COVID-19 infection were recruited from 12 European hospitals. The following epidemiological and clinical outcomes have been studied: age, sex, ethnicity, comorbidities, general and otolaryngological symptoms. Patients completed olfactory and gustatory questionnaires based on the smell and taste component of the National Health and Nutrition Examination Survey, and the short version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS).
A total of 417 mild-to-moderate COVID-19 patients completed the study (263 females). The most prevalent general symptoms consisted of cough, myalgia and loss of appetite. Face pain and nasal obstruction were the most specific otolaryngological symptoms. 85.6% and 88.0% of patients reported olfactory and gustatory dysfunctions, respectively.
There was a significant association between both disorders (p<0.001). Olfactory dysfunction (OD) appeared before the other symptoms in 11.8% of cases. The sQO-NS scores were significantly lower in patients with presumed anosmia compared with normosmic or presumed hyposmic individuals (p=0.001). Among the 18.2% of patients without nasal obstruction or rhinorrhea, 79.7% had olfactory dysfunction. The early olfactory recovery rate was 44.0%. Females were significantly more affected by olfactory and gustatory dysfunctions than males (p=0.001).
The researchers stated that olfactory and gustatory disorders are prevalent symptoms in European COVID-19 patients, who may not have nasal symptoms. The sudden olfactory and gustatory dysfunctions need to be recognized by the international scientific community as important symptoms of the COVID-19 infection.