The aim of this multicenter study was to investigate and characterize the occurrence of olfactory and gustatory disorders in patients with laboratory-confirmed COVID-19 infection. A total of 417 mild-to-moderate COVID-19 patients were included in the study; in particular 85.6% and 88.0% of patients reported olfactory and gustatory dysfunctions, respectively. Moreover, olfactory dysfunction appeared before the other symptoms of the infection in 11.8% of cases. The early olfactory recovery rate was 44.0%. Females were significantly more affected by olfactory and gustatory dysfunctions than males. The authors concluded that olfactory and gustatory disorders are prevalent symptoms in European COVID-19 patients, who may not have nasal symptoms such as nasal obstruction or rhinorrhea. Moreover, they underlined how sudden anosmia or ageusia need to be recognized as important symptoms of the COVID-19 infection.
https://www.ncbi.nlm.nih.gov/pubmed/32253535
by Marialuisa Zedde and Francesco Cavallieri