ABSTRACT
BACKGROUND: The aetiology of idiopathic facial nerve palsy (Bell's palsy, BP) and sudden sensorineural hearing loss (SSNHL) are not known. It has been proposed that common respiratory tract viruses play a part in the pathophysiology of these diseases. OBJECTIVES: The incidence of many infectious diseases decreased during the lockdown of the society that took place during the COVID-19 pandemic. We investigated a possible change in the incidence of BP and SSNHL during the lock-down. MATERIAL AND METHODS: We searched the patient records for all BP and SSNHL cases between 1 Jan 2017 - 31 Aug 2020 at the hospital district of Helsinki and Uusimaa that covers a population of about 1.2 million. RESULTS: The mean monthly incidence on BP decreased during the COVID-19 pandemic lock-down. No change in the SSNHL incidence was discovered. CONCLUSIONS AND SIGNIFICANCE: There is reason to speculate that one aetiologic reason for BP are transmittable respiratory tract pathogens.