1 INTRODUCTION
Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 evolved to a pandemic [1,2]. There are reports of early olfactory and/or gustatory dysfunction even before molecular confirmation of SARS-CoV-2 infection [1-7]. Smell and taste complaints in COVID-19 appear to have somehow different features compared to those related to other viruses [8-10].
The primary hypothesis of this study was that COVID-19-infection causes a functional deterioration of gustatory function, as measured by EGM, at the regions supplied by the trigeminal, facial and glossopharyngeal nerves. Secondary hypotheses of our study were: a. that COVID-infection causes structural alterations of the taste buds, more specifically of the fungiform papillae, b. that COVID-infection induces a functional olfactory decline, c. that COVID-infection causes structural alterations of the nasal mucosa, d. that structural and functional changes regarding olfaction and taste correlate and e. that the above structural and functional changes improve with time, more specifically 4 to 6 weeks after hospital discharge.