Smell and taste disorders: warning signs for SARS-CoV-2 infection^☆

Brazil, the second most populous country in the Americas, faces a public health crisis with more than 66,000 confirmed cases and 5000 deaths from COVID-19. Due to the worldwide demand for tests to identify patients infected with SARS-CoV-2, health strategies are severely hindered by the lack of tests that can guide the correct and immediate isolation of positive cases of COVID-19. In the last few weeks, it was observed that the loss of smell/taste associated with COVID-19 has been a frequent complaint, mainly identified when evaluating the patient with appropriate tools. However, how useful are these symptoms in clinical practice, and especially in the absence of tests for SARS-CoV-2?

In a recent study, Menni et al.¹ showed that the combination of loss of smell/taste, fever, cough, was predictive for a positive test for COVID-19, with sensitivity of 0.54 (0.44; 0.63), specificity of 0.86 (0.80; 0.90) and, overall, the loss of smell/taste had a positive predictive value of 61.7%.

A multicenter European study also showed that anosmia and ageusia were independently and strongly associated with a positive COVID-19 test (anosmia: aOR = 10.9; 95% CI: 5.08–23.5; ageusia: aOR = 10, 2; 95% CI: 4.74–22.1).² In Brazil, without sufficient tests for a massive assessment of the population, especially in regions with few diagnostic and poor resources, the recommendation to isolate a patient with anosmia/ageusia complaint, starting from the medical consultation itself, has become a health strategy to try to control the spread of the virus.

In fact, the loss of smell/taste does not depend on nasal obstruction/rhinorrhea and can begin even before the typical signs/symptoms of COVID-19, thus becoming warning signs even in oligosymptomatic patients and, especially, in the initial stage of the disease, when high viral replication and transmissibility occur. The recovery of smell/taste, when it occurs, usually does so in the first two weeks after the resolution of COVID-19.³ However, new interpretations appear every week, and we believe that valuing and actively questioning the patient about olfactory/gustatory disorders can help, implemented not only by otorhinolaryngologists, but the entire health team working on the front line of the pandemic control.

Conflicts of interest

The authors declare no conflicts of interest.

• ☆
  Please cite this article as: Costa KV, Carnaúba AT. Smell and taste disorders: warning signs for SARS-CoV-2 infection. Braz J Otorhinolaryngol. 2020;86:393–4.

References

• ¹
  Menni C, Valdes A, Freydin MB, Ganesh S, Moustafa JE-S, Visconti A, et al. Loss of smell and taste in combination with other symptoms is a strong predictor of COVID-19 infection. medRxiv. 2020. Available from: https://www.medrxiv.org/content/10.1101/2020.04.05.20048421v1.full.pdf+html [accessed 15.05.20]
  » https://www.medrxiv.org/content/10.1101/2020.04.05.20048421v1.full.pdf+html
• ²
  Yan CH, Faraji F, Bs DPP, Boone CE, Deconde AS(a). Association of chemosensory dysfunction and COVID-19 in patients presenting with influenza-like symptoms. Int Forum Allergy Rhinol. 2020;10:806-813.
• ³
  Lechien JR, Chiesa-Estomba CM, De Siati DR, Horoi M, Le Bon SD, Rodriguez A, et al. Olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (COVID-19): a multicenter European study. Eur Arch Otorhinolaryngol. 2020;277:2251-2261.

Publication Dates

• Publication in this collection
  28 Aug 2020
• Date of issue
  Jul-Aug 2020