Increase in infected corneal ulcerations in dogs during the northern Colorado's 2020 wildfire season

Objective In the fall of 2020, Colorado experienced the two largest wildfires in state history. The smoke blanketed the college town of Fort Collins, Colorado, the location of the Veterinary Teaching Hospital at Colorado State University (CSU-VTH). The objective for this cross-sectional observational study was to evaluate how these wildfires and the corresponding elevated air quality index (AQI)) was associated with infected corneal ulcerations in dogs when compared to the two previous years. Animals Seventeen dogs were included in this study. Procedures Medical records from dogs presented to the CSU-VTH ophthalmology service with infected corneal ulcerations in August, September, and October of 2020, 2019, and 2018 were evaluated. Only corneal ulcerations with growth on their microbial cultures were included in this study. Results The study revealed a significant increase in prevalence of infected corneal ulcerations in dogs presented to the CSU-VTH during the three wildfire months of 2020 that is, 3.5% (9/255) when compared with the two previous years, 2019: 1.0% (4/383, p = 0.04), and 2018: 0.9% (4/457) (p = .01). The AQI (mean +/- standard error) was also significantly elevated for dogs that presented with infected corneal ulcerations in 2020 (70.2 +/- 5.8) compared with 2019 (19.7 +/- 8.7) and 2018 (45.6 +/- 8.7) (p < .01). Conclusions and clinical relevance Elevation of AQI from wildfires seems to be correlated with an increased prevalence of infected corneal ulceration in dogs. As the duration and frequency of wildfires continues to rise globally, the effects of these wildfires on animal health should be investigated further.