Chemosensory Dysfunction in Patients with COVID-19: What Do We Learn from the Global Outbreak?

Purpose of review Chemosensory dysfunction in the patients with COVID-19 has been reported frequently in the studies from different regions of the world. However, the prevalence of smell and/or taste disorders presents significant ethnic and geographic variability. In addition, the pathogenesis of chemosensory dysfunction remains unclarified. Recent findings This is a narrative review on the recent state of the prevalence, mechanism, and diagnostic and therapeutic strategy of chemosensory dysfunction in COVID-19 patients during the global pandemic. The chemosensory dysfunction was analysis based on recent studies, which either used questionnaires, Likert scales (0-10), or smell tests to estimate the smell and taste dysfunction. The ethnic and geographic difference of the prevalence of smell and/or taste disorders and the potential underlying mechanisms have been discussed. Several suggestions on the diagnosis and treatment of COVID-19 patients with smell and taste disorders were summarized for the physicians. This review provides a comprehensive overview of the current studies regarding the chemosensory dysfunction during the COVID-19 worldwide outbreak.