Wildfires are becoming healthcare emergencies

Ontario's recent wildfires are a reminder that the health impacts of climate change extend well beyond the communities directly affected by the flames.

A recent study published in Nature demonstrates just how far those impacts can reach. The study estimated that smoke from the 2023 Canadian wildfires exposed 354 million people across North America and Europe to wildfire-related PM2.5 pollution, with an estimated 5,400 acute deaths and 64,300 chronic deaths attributable to this exposure across the two continents.[1]

The evidence shows that exposure to wildfire smoke increases the risk of healthcare utilization by 7% overall, including a 9% increase in emergency department visits and a 4% increase in hospital admissions.[2] In the Canadian studies included in the meta-analysis, wildfire smoke exposure was associated with 27% higher odds of disease-related healthcare utilization (OR 1.27; 95% CI: 1.10–1.46).[2]

Another recent systematic review of 139 peer-reviewed studies found that wildfires affect far more than respiratory health. Beyond asthma and cardiovascular disease, they disrupt healthcare access, contribute to poor mental health, displace communities, and create broader social and economic consequences that healthcare systems must manage long after the smoke has cleared.[3]

Emerging evidence also suggests that healthcare demand may peak after the smoke clears. A 2026 study observed a five-fold increase in respiratory-related healthcare claims during the week following wildfire smoke episodes, highlighting the importance of planning not only for the emergency itself, but also for the delayed surge in healthcare utilization.[4]

Collectively, the evidence points to a broader shift in thinking.

The question is no longer: How do we respond to wildfires?

It's: How prepared are our healthcare systems for climate-related health emergencies?

Healthcare organizations should be asking:

• Are our emergency preparedness plans designed for prolonged smoke events?

• Which populations are most vulnerable?

• Do we have the capacity to manage delayed increases in demand?

• How will we measure whether our preparedness strategies actually work?

  
  

As climate-related events become more frequent, resilience will not be defined by how effectively we respond during an emergency. It will be defined by how well we prepare before the next one.

The W&W Team

Sources:

1. Zhang Q, Wang Y, Xiao Q, Geng G, Davis SJ, Liu X, et al. Long-range PM2.5 pollution and health impacts from the 2023 Canadian wildfires. Nature. 2025;645:672-678. doi:10.1038/s41586-025-09482-1.

2. Fu P, Mago V. The association between fire smoke exposure and emergency department (ED) visits and hospital admissions (HA): a systematic review and meta-analysis. Heliyon. 2024;10(18):e38024. doi:10.1016/j.heliyon.2024.e38024.

3. Ye X, Ye Y, Huang X, Onega T. Wildfires and public health: a comprehensive review of human-centric studies. GeoHealth. 2026;10:e2025GH001534. doi:10.1029/2025GH001534.

4. Mayes JE Jr, Fufaa GD. Public health impact of wildfire smoke exposure: analysis of respiratory-related Medicaid claims in Wyoming. Cureus. 2026;18(2):e102912. doi:10.7759/cureus.102912.