ABSTRACT
Background: Olfactory dysfunction (OD) is a common symptom of COVID-19 with a prevalence of 5 to 98 percent according to geographical region and method of evaluation. Although recovery is reported within the first month in many cases, long-term observations are rare. Therefore, we aimed to assess the course of chemosensory function in COVID-19 patients within three to six months after the infection with SARS-CoV-2. Methodology: Sixty-two patients (43f and 19m;mean age/ SD: 40.513.6 years;range: 18-68 years) with SARS-CoV-2 infection and subjective OD participated in this singlecenter study. At first, patients performed questionnaires and chemosensory tests at home, and then, further psychophysical tests were performed at the clinic. Results: Three to six months after the acute infection 80% still showed some degree of OD by applying orthonasal olfactory test (“Sniffin' Sticks / TDI”). After a mean interval of 219.1 days (SD 67.6;range: 113-330) between first day of OD and follow-up testing, the mean TDI score was 26.8 points (SD 5.5;range 5.0-37.5). Furthermore, 64.5% reported improvement, 6.5% deterioration and 29% no change of OD until follow-up. Conclusions: The prevalence of persisting OD associated with SARS-CoV-2 may be higher than expected. Moreover, subjective assessment of chemosensory function seems to improve, but reconvalescence fails to appear in the majority.