Smell and taste disorders in Spanish patients with mild COVID-19

Introduction: Coronavirus disease 2019 (COVID-19) has spread rapidly throughout the world. Smell and/or taste disorders have emerged as a very frequent symptom as the disease has spread in Europe. Spain is one of the European countries with the highest number of infections.

Objective: This study aimed to investigate the clinical progression of smell and taste disorders in Spanish patients with mild COVID-19.

Methods: An online survey was used to conduct a cross-sectional study of patients who presented sudden smell and/or taste disorders during the 2 months of total lockdown due to COVID-19 in Spain.

Results: In our sample, 91.18% of respondents with impaired smell and/or taste and who were able to undergo PCR testing were positive for SARS-CoV-2 infection. Anosmia and ageusia presented in isolation in 6.5% of participants. The remaining 93.5% presented other mild symptoms: headache (51.6%), cough (51.6%), myalgia (45.2%), asthaenia (38.7%), nasal congestion or rhinorrhoea (35.5%), fever (41.9%), low-grade fever (29.0%), odynophagia (25.8%), or diarrhoea (6.5%). The mean duration of anosmia was 8.33 days, with patients subsequently manifesting hyposmia; complete resolution occurred after a mean of 17.79 days. In 22.6% of respondents, olfactory deficits persisted. All participants recovered their sense of taste.

Conclusions: Olfactory and gustatory disorders are prevalent symptoms in mild COVID-19. Most patients do not present associated nasal congestion or rhinorrhoea and a small group of patients present these alterations in isolation.

Keywords: Ageusia; Anosmia; COVID-19; Hiposmia; Hyposmia; Pandemia; Pandemic.