Loss of smell or taste as the only symptom of COVID-19

Abstract

Background: Olfactory and taste disorders (OTDs) have recently been reported among patients with COVID-19, and it has been hypothesised that oral and nasal tissues may contain host cells of SARS-CoV-2. We report on two cases (spouses) with SARS-CoV-2 infection with self-reported OTDs, but otherwise no typical respiratory symptoms of COVID-19.

Case presentation: A man in his nineties (index patient) had respiratory symptoms and dysgeusia, and was diagnosed with COVID-19. His daughter-in-law and son had no respiratory COVID-19 symptoms. However, they experienced complete loss of smell and taste, respectively, 7 and 10 days after their first close contact with the index patient. Both tested positive for SARS-CoV-2 RNA.

Interpretation: Our case histories support recent reports hypothesising that anosmia and ageusia may be the only symptoms of SARS-CoV-2 infection, and that SARS-CoV-2 may infect oral and nasal tissues. Together, these findings may inform future research, diagnosis, prevention and treatment of COVID-19.