Loss of Taste and Smell Sensation in COVID-19: A Questionnaire Based Multicontinental Study with Review

Abstract

Introduction: Taste buds are the peripheral organs of gustation and are located mainly in the tongue epithelium and palate. Taste buds further sample the chemical makeup of foods and beverages for nutrient content, palatability, and potential toxicity. On the other hand, the smell acts as a major factor and mostly functions involuntarily thereby identify chemical makeup and protecting from potential toxic insult. The coronavirus disease 2019 (COVID-19) is an ongoing viral pandemic that emerged from East Asia and quickly spread to the rest of the world. An important highlight is an atypical new presentation of the disease: patients with olfactory and gustatory dysfunctions.
 Objectives: To know whether the loss of taste and smell are a reliable symptomatic indicator in early diagnosis of COVID as well as how it impacts on the nutrition and early patient’s recovery.
 Results: A questionnaire originally developed by AAO – NHS (American academy of oto – laryngology neck and head surgery) was modified to include the questions related to loss of taste. We have included a total of 512 patient of which 82.4% were females. The common risk factor reported by our patients was close contact with a potentially confirmed case which accounted for 46.1%. The common comorbidities reported in the population has largely been related to breathing problems in the form of asthma 10.2%, sinus and smoking allergies of 5.7% which is a known factor in the spread of Covid in these patients. We have noticed in our population that there was a loss of smell and taste noticed in all the subjects and among them 66.5% reported with anosmia and 52.3% reported with ageusia which was either overlooked or not understood by most of the patients. Hyposmia and Parosmia was 18.6% and 14.9% respectively while Hypogeusia and dysgeusia was 32.2% and 15.4% indicating that though complete loss of taste is less when compared to complete loss of smell but alteration in taste is much higher and was felt for a much longer duration of time and often reported but complete remission from loss of taste is not completed.
 Conclusion: Loss of smell and taste should be considered as one of the reliable symptomatic indicators to covid infection and an active attempt should be made for its early remission for the patients to return back to normal intake of food leading to adequate nutrient supply