Québec Wildfires and Respiratory Emergency Department Visits in Charlottesville, Virginia

The decline in air quality from wildfires is known to have detrimental health impacts locally, but less is known about the effects far from the source. To address this gap, we analyzed visits to the University of Virginia Emergency Department from 2017 to 2023 by examining the impact of elevated PM_2.5 levels on respiratory visits. For this analysis, high exposure days were defined as those with PM_2.5 levels 2 or more standard deviations above the 2017-2023 average, specifically during the summer of 2023 when the Québec wildfires plume was advected over central Virginia. The results showed higher odds ratios on high PM_2.5 days compared to dates with normal exposure (1.190 [1.026,1.380]). This result was observed in males (1.388, [1.122,1.716]) and in white individuals (1.220 [1.009, 1.475]). Additionally, a comparison of mean ED visit departures (detrended and deseasoned) revealed that same day respiratory visits were significantly elevated on high exposure days (mean departure difference =  + 1.886, p = 0.027). These findings indicate that wildfires can have measurable health impacts in areas far from their origin.