Shifting patterns of acute otitis media and mastoiditis through COVID-19 Era: analysis of pre-pandemic, pandemic, and post-pandemic dynamics.

Objective: To evaluate the impact of the COVID-19 pandemic on acute otitis media (AOM) and acute mastoiditis (AM) by analyzing longitudinal changes in disease incidence, clinical presentations, complications, and microbial patterns across pre-pandemic, pandemic, and post-pandemic periods.

Methods: A retrospective cohort study examining pediatric AOM and AM cases (age ≤ 15 years) at a tertiary medical center between March 2015 and February 2024. Cases were categorized into three periods: pre-COVID (March 2015-February 2020), lockdown (March 2020-February 2021), and post-lockdown (March 2021-February 2024). We assessed disease incidence, microbiology, complications, and clinical outcomes.

Results: Among 6,673 patients (6,221 AOM, 452 AM), AOM cases significantly decreased during lockdown (301/year) vs. pre-COVID (658/year) (p = 0.041) but returned to baseline in post-lockdown (758/year). AM showed similar trends without statistical significance. Complications of AM per case were highest during lockdown (0.52) vs. pre-COVID (0.39), with increased mastoidectomy rates (28% vs. 18.4%). Positive culture rates increased post-COVID (52.7-73.7%), and mean hospitalization duration was longest during lockdown (8.56 days vs. 7.96 pre-COVID, p = 0.005).

Conclusions: The COVID-19 pandemic induced a significant temporary reduction in acute otitis media and acute mastoiditis cases, primarily during lockdown periods. Despite the initial decrease, disease incidence returned to pre-pandemic baseline levels post-lockdown. Notably, the lockdown period showed higher complication rates and longer hospitalization durations, suggesting potential delays in medical care, but overall disease patterns remained fundamentally unchanged.