Wildfire Smoke Exposure Worsened COVID-19 Outcomes

A new study published in Science Advances found that wildfire smoke significantly worsened the toll of COVID-19 in California, Oregon, and Washington during the record 2020 fire season. Researchers linked spikes in fine particulate matter (PM2.5: tiny particles less than 2.5 micrometers in diameter that burrow deep into the lungs) with thousands of additional COVID-19 cases and hundreds of deaths.

PM2.5 is considered one of the most harmful components of smoke because of its ability to slip past the body’s natural defenses and trigger inflammation in the respiratory system. The study suggests that this immune “distraction” may weaken the body’s ability to fight off SARS-CoV-2, effectively creating a one-two punch: wildfire smoke stresses the lungs, while COVID-19 exploits the compromised defenses.

 

Citation

Zhou, X., et al. (2021). Excess of COVID-19 cases and deaths due to fine particulate matter exposure during the 2020 wildfires in the United States. Science advances, 7(33), eabi8789. https://doi.org/10.1126/sciadv.abi8789