It is necessary to assess olfactory and gustatory function in post covid‐19 patients, due to the omicron variant infection

Abstract

To the Editor:Boscolo-Rizzo et al. 1 concluded that although a proportion of patients recovered from enduring smell/taste dysfunction more than 1 year after coronavirus disease 2019 (COVID-19), some cases still showed a noteworthy remaining olfactory dysfunction 2 years after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection compared to matched normal subjects.Initial reports stated that the most frequent symptoms of COVID-19 infection were fever, cough, dyspnea, and myalgia or fatigue. 2,3 Several authors later described an association between COVID-19 and altered olfactory and taste functions. [4][5][6][7][8] SARS-CoV-2 enters the nasal and mouth tissues through the angiotensin-converting enzyme 2 (ACE2), which is copious in the nose. By entering the nose and mouth through this protein, it may cause temporary damage to the smell and taste nerves. [5][6][7][8][9][10][11][12] New variants of SARS-CoV-2 began to circulate due to virus mutations. The Omicron variant emerged in November 2021, although new lineages continue to spread globally. The SARS-CoV-2 omicron variant has significantly increased COVID-19 diagnoses with less severe clinical manifestations and decreased hospitalizations. The omicron wave has swelled faster than previous waves, completely displacing the delta variant within weeks and creating new worldwide concerns about the ability to achieve final pandemic control. 13,14 The symptoms associated with Omicron differ from "traditional" COVID-19 symptoms, more closely resembling those of the common cold. 15 One major COVID-19 symptom is rare in omicron patients: loss of taste and smell. 16,17 Some research suggested that 48% of people carrying the original mutation of the novel coronavirus lost smell, and 41% had a loss of taste; these numbers decreased to 23% for loss of taste and 12% for loss of smell among omicron-infected patients. 18 Consequently, many people may not realize they have contracted COVID-19 because fewer experience cough, fever, or loss of taste or smell. A virus in the higher respiratory tract is associated with increased transmissibility but with less severe disease, exhibiting similarities with flu strains. 19