key: cord-0730103-dlzs39wc authors: Marinosci, Annalisa; Landis, Basile N.; Calmy, Alexandra title: Possible link between anosmia and COVID-19: sniffing out the truth date: 2020-04-17 journal: Eur Arch Otorhinolaryngol DOI: 10.1007/s00405-020-05966-0 sha: abe6da15f4a29d3a9c2e077f096b5d756fae2b21 doc_id: 730103 cord_uid: dlzs39wc nan biopsies have suggested a direct damage of the olfactory epithelium [8] . A recent study demonstrated that nasal epithelial cells display a very high angiotensin converting 2 (ACE2) expression in SARS-CoV-2 infection, thus allowing wide viral entry [9] . Consequently, peripheral nerve injury might occur causing anosmia, frequently observed in infected patients in our clinical practice. In light of the striking increase of reports of anosmia in association with the classically reported COVID-19 infection symptoms, we would like to propose the following assumptions: • Smell and/or taste loss may be a consistent accompanying symptom of SARS-CoV-2 infection. Most observations suggest transient anosmia with recovery after days to weeks, but it remains open in how many cases this impairment remains irreversible. • It raises the question to what extent the olfactory epithelium could serve as a nose-brain entry path, as this has been suggested in other diseases with accompanying olfactory impairment [10] . Although Li et al. [11] reported that some patients with COVID-19 showed neurological signs, such as headache, nausea and vomiting, it remains unclear if SARS-COV-2 induces short-or long-term neurological manifestations. • It remains to be seen if anosmia could predict acute respiratory failure in patients with COVID-19 as awareness of the presence of this impairment may have a guiding significance for the prevention and treatment of SARS-CoV-2-induced respiratory failure. Of note, anecdotal reports of this symptom have been recognized as sufficiently serious by otolaryngology societies in France, the United Kingdom and the USA and their members are actively recommended to look for it and to consider any new, unexplained anosmia as a potential COVID-19 case and to take all the necessary precautions. In conclusion, we believe that the scientific community should focus on this accompanying symptom to clarify the role of anosmia in Many questions need to be addressed and patients should probably be tested for olfaction when this is possible. Only a serious follow-up of this clinical observation will help us to understand the sudden rise of anosmia in parallel to the SARS-CoV-2 outbreak. Novel coronavirus (2019-nCoV) situation report-64 Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2 Olfactory and gustatory dysfunctions as a clinical presentation of mild to moderate forms of the coronavirus disease (COVID-19): a multicenter European study Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding New chemosensory component in the US national health and nutrition examination survey (NHANES): first-year results for measured olfactory dysfunction New evidence for high occurrence of olfactory dysfunctions within the population Complaints of olfactory disorders: epidemiology, assessment and clinical implications The olfactory nerve: a shortcut for influenza and other viral diseases into the central nervous system SARS-CoV-2 entry genes are most highly expressed in nasal goblet and ciliated cells within human airways The olfactory vector hypothesis of neurodegenerative disease: is it viable? The neuroinvasive potential of SARS-CoV2 may play a role in the respiratory failure of COVID-19 patients Conflict of interest None declared.