Wildfire-Linked ED Encounters Increased Eightfold With Onset of LA Wildfires

THURSDAY, Feb. 6, 2025 (HealthDay News) — The percentage of wildfire-associated emergency department encounters increased with onset of the Los Angeles County (LAC) wildfires in January 2025, according to research published in the Feb. 6 issue of the U.S. Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.

Emily Kajita, M.P.H., from the Los Angeles County Department of Public Health, and colleagues reviewed syndromic surveillance data to examine trends in all-cause and wildfire-associated emergency department encounters contemporaneous with the LAC wildfires. If fire or smoke inhalation-related terms were present in chief complaints and diagnoses, encounters were classified as wildfire-associated. Three periods were analyzed: Dec. 17, 2024, to Jan. 6, 2025 (baseline); Jan. 7, 2025, to Jan. 12, 2025 (phase 1: the first six days of the wildfires); and Jan. 13, 2025, to Jan. 19, 2025 (phase 2).

The researchers found that from baseline to phase 1, there was a 9 percent decrease in the average number of daily all-cause emergency department encounters (91 percent of baseline encounters), followed by an increase to 95 percent of baseline encounters in phase 2. There was an eightfold increase in the average percentage of emergency department encounters that were wildfire-associated, from 0.06 percent at baseline to 0.52 percent in phase 1, followed by a decrease to 0.20 percent in phase 2. The percentage of wildfire-associated emergency department encounters peaked on Jan. 8, 2025, at 1.01 percent. The increase in average percentage of wildfire-associated emergency department visits increased in alignment with the increase in average daily air quality index from 75 (moderate level of concern) at baseline to 110 (unhealthy for sensitive groups) in phase 1, followed by a decrease to 58 (moderate) in phase 2.

“These data demonstrate that the wildfires were associated with a decrease in total emergency department encounters across LAC, and that wildfire-associated emergency department encounters were temporally associated with worsening air quality,” the authors write.

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