The Effect of Wildfires on the Rate of Violent Trauma in California

Introduction: Natural disasters may impact behavior and cause social destabilization. Recent research suggests potential changes in violent trauma rates following natural disasters; however, there is no clear evidence regarding the impact of wildfires. The study sought to evaluate the impact of wildfires on rates of violent trauma in California. Methods: Data from the California EMS Authority between 2017-2022, following 30 wildfires, was used. Violent trauma totals were calculated within the county of the wildfire incidence. The baseline rate was established two weeks before the fire, the active period expanded from the start of the fire through containment, and the post period extended two weeks post-containment. Multivariable linear regression was performed to compare changes in violent trauma rates and county-level co-variables. Analyses were adjusted for county median income, population, total structural damage, and the county baseline rate. Results: The baseline, active fire, and post-containment rate of violent trauma per county were 16. 2, 16. 1, and 13. 2 patients per week, respectively. Testing showed no significant difference in the rates of violent trauma during an active wildfire compared to baseline (z=0. 495, p=0. 62), and following the wildfire versus baseline (z=0. 51, p=0. 61). Further analysis showed that for every 10, 000 decrease in median income, there was an increase in weekly violent trauma by 1. 68 cases (95% CI 0. 0048, 3. 31; p=0. 049) during the wildfire, and an increase by 0. 94 cases (95% CI, -0. 32, 2. 2; p=0. 14) post wildfire. Conclusion: The findings demonstrate a potential reduction in violent trauma with increased county income, indicating potential disparities in community resilience based on income. Research with a larger population of wildfires is needed to further elucidate the impacts of wildfires and the potential protective factors against fluctuations in violence rates.