JMIR Publications

ABSTRACT

Background:

Acute otitis media is a common complication of viral upper respiratory infections. However, large-scale epidemiological data on this association at the population level are scarce. This study aimed to investigate the ecological association between influenza-like illness (ILI) and emergency room (ER) visits for ear and mastoid diseases in Taiwan over a nine-year period.

Objective:

The present study aims to investigate the temporal association between the national incidence of influenza-like illness and emergency room visits for ear and mastoid process diseases in Taiwan over a nine-year period from 2016 to 2024. By leveraging nationwide public health data, we seek to: (1) describe and compare the temporal trends of national ILI activity and H60-H95 emergency visits; (2) quantify the correlation between their annual aggregates; and (3) discuss the observed patterns, particularly the impact of the COVID-19 pandemic, within the context of public health.

Methods:

This was a retrospective, national-level ecological time-series study using publicly available surveillance data from 2016 to 2024. National monthly ER visit counts for ILI were obtained from the Taiwan Centers for Disease Control. National annual mean ER visit rates for ear and mastoid diseases (ICD-10-CM: H60-H95) were calculated from the Taiwan Ministry of Health and Welfare Statistics Portal, which provides county-level data. We assessed the correlation between the annual aggregates of these two national-level metrics.

Results:

A moderate, positive, but not statistically significant correlation was observed between the total annual national ILI visits and the national annual mean H60-H95 ER visit rate (Pearson's r = 0.546, p = 0.128, n=9 years). Visual inspection of the time-series data revealed a notable parallel trend, with both ILI activity and ear disease ER visits declining concurrently during the COVID-19 pandemic (2020–2021) and subsequently recovering. ILI activity demonstrated a consistent and strong winter seasonality.

Conclusions:

This study observed a temporal association between national ILI trends and emergency visits for ear diseases, particularly evidenced by their synchronous decline during the COVID-19 pandemic. While the annual correlation did not reach statistical significance, likely due to the limited number of years in the time series, the observed trends support the public health value of respiratory virus prevention. Future research with longer time-series data is warranted to confirm the statistical significance of this association.