Differential Recovery Trajectories of Emergency Otolaryngologic Conditions across the COVID-19 Pandemic: A Six-year Longitudinal Study from an Urban Emergency Center

The study analyzed the impact of the COVID-19 pandemic on emergency otolaryngologic conditions in 99,324 patients at an urban clinic in Osaka, Japan, between 2019 and 2024. Total emergency visits declined to approximately half of baseline in 2020 and gradually recovered through 2024, but did not fully return to pre-pandemic levels. Infectious respiratory diseases fell to 23 to 50 percent of baseline in 2020 and partially recovered to 69 to 103 percent by 2024. However, laryngitis exceeded baseline levels, reaching 132 percent in 2023. Sudden sensorineural hearing loss dropped to 39 percent in 2020 and remained reduced through the end of the study. Traumatic emergencies showed incomplete recovery, reaching only 55 to 69 percent of baseline by 2024. The results demonstrate heterogeneous, condition-specific recovery trajectories that reflect changes in pathogen burden and alterations in healthcare-seeking behaviors among patients.