SARS-CoV-2 (CoV-2) is a coronavirus which is causing the actual COVID-19
pandemic. The disease caused by 2019 new coronavirus (2019-nCoV) was named
coronavirus disease-19 (COVID-19) by the World Health Organization in February 2020.
Primary non-specific reported symptoms of 2019-nCoV infection at the prodromal phase are malaise, fever, and dry cough. The most commonly reported signs and symptoms are
fever (98%), cough (76%), dyspnea (55%), and myalgia or fatigue (44%). Nonetheless,
recent reports suggest an association between COVID-19 and altered olfactory and taste
functions, although smell seems to be more affected than taste. These associations of
smell and taste dysfunctions and CoV-2 are consistent with case reports describing a
patient with SARS with long term anosmia after recovery from respiratory distress, with
the observation that olfactory function is commonly altered after infection with endemic
coronaviruses, and with data demonstrating that intentional experimental infection of
humans with CoV-299 raises the thresholds at which odors can be detected. Post-viral
anosmia and is one of the leading causes of loss of sense of smell in adults, accounting
for up to 40% cases of anosmia. Viruses that give rise to the common cold are well known
to cause post-infectious loss, and over 200 different viruses are known to cause upper
respiratory tract infections. I reviewed the possible mechanisms of smell and taste loss in
COVID-19. I concluded that since the existence of such a relationship is likely, it is highly
recommended that those patients who experience complications such as smell and/or taste
loss, even as unique symptoms, should be considered as potential SARS-CoV-2 virus
carriers.