Prevalence and Duration of Acute Loss of Smell or Taste in COVID-19 Patients

Abstract

Initially, acute loss of smell (anosmia) and taste (ageusia) was not considered important symptoms for coronavirus disease 2019 (COVID-19). To determine the prevalence of these symptoms and to evaluate their diagnostic significance, we (approximately 150 physicians of the Daegu Medical Association) prospectively collected data of cases of anosmia and ageusia from March 8, 2020, via telephone interview among 3,191 patients in Daegu, Korea. Acute anosmia or ageusia was observed in 15.3% (488/3,191) patients in the early stage of COVID-19 and in 15.7% (367/2,342) patients with asymptomatic-to-mild disease severity. Their prevalence was significantly more common among females and younger individuals (P = 0.01 and P < 0.001, respectively). Most patients with anosmia or ageusia recovered within 3 weeks. The median time to recovery was 7 days for both symptoms. Anosmia and ageusia seem to be part of important symptoms and clues for the diagnosis of COVID-19, particularly in the early stage of the disease.

Keywords: Ageusia; Anosmia; COVID-19; Loss of Smell; Loss of Taste.

Fig. 1. Proportion of anosmia or ageusia in patients with coronavirus disease 2019 confirmed by polymerase chain reaction.

Fig. 2. Graph of recovery from anosmia and ageusia among patients with coronavirus disease 2019. (A) Recovery from anosmia. (B) Recovery time pattern of anosmia. (C) Recovery time pattern of ageusia. (D) Pattern of persistence of anosmia according to age group.