Wildfires raging in the West may also be fueling the coronavirus pandemic, according to a new study that has linked thousands of COVID-19 infections and hundreds of deaths to smoke from the blazes.
Smoke from wildfires contains high levels of dangerous fine particulate matter or “PM 2.5,” which is known to blunt the body’s white blood cell function in the lungs. The impact compromises the body’s immune response, making people more susceptible to the virus.
Harvard University researchers estimated that there were nearly 20,000 extra COVID-19 infections and 750 deaths associated with wildfire smoke exposure between March 15 and Dec. 16, 2020 in three western states.
The study, published Friday in Science Advances, was co-authored by members of Harvard’s T.H. Chan School of Public Health.
Using publicly available daily data on both COVID-19 cases, deaths and PM 2.5 in Washington, Oregon and California, the researchers estimated the association between PM 2.5 and the “epidemiological dynamic” of cases and deaths, adjusting for “confounding factors” like weather, seasonality, long-term trends, mobility and population.
The Dixie Fire burns down a hillside towards Diamond Mountain Rd. near Taylorsville in Plumas County, Calif., on Friday, Aug. 13, 2021.
(AP Photo/Noah Berger)
Using their statistical model, the team – also from the John A. Paulson School of Engineering and Applied Sciences and the Environmental Systems Research Institute in Redlands, California – found that wildfire smoke had an impact on COVID-19 cases and deaths for up to four weeks after exposure.
Across all counties, the study found that a daily increase of 10 µg/m3 in PM 2.5 each day for 28 days was associated with an 11.7% increase in coronavirus cases and an 8.4% increase in deaths.
Washington’s Whitman County showed the largest effect on COVID-19 cases, with the percentage of total cases attributable to high levels of PM 2.5 of wildfire days at 18.2%.
Additionally, Calaveras, California, showed the largest effect on coronavirus deaths with a percentage of total COVID-19 deaths attributable to high levels of PM 2.5 on wildfire days at 137.4%.
The Golden State’s Butte County – where the North Complex Fire wreaked havoc last year – topped the list for both percentages, with 17.3% of total cases attributable to high levels of PM 2.5 on wildfire days and 41% of total COVID-19 deaths attributable to high levels of PM 2.5 on wildfire days.
According to the National Interagency Fire Center, there are now more than 25,000 wildland firefighters and support personnel working on 103 large fires and complexes that have burned more than 2.4 million acres.
More than 40,000 wildfires have burned 3,893,239 acres across the country this year, the agency said.
In addition, coronavirus cases in the U.S. have surged recently with the spread of the highly transmissible delta variant.
“The year 2020 brought unimaginable challenges in public health, with the convergence of the COVID-19 pandemic and wildfires across the western United States. In this study we are providing evidence that climate change — which increases the frequency and the intensity of wildfires — and the pandemic are a disastrous combination,” Francesca Dominici, a senior author of the study, said in a release.
Kecia Harris, with the environmental services department, cleans the room of a patient fighting the coronavirus at Our Lady of Angels Hospital in Bogalusa, La., Monday, August 9, 2021.
(Chris Granger/The Advocate via AP)
“Climate change will likely bring warmer and drier conditions to the west, providing more fuel for fires to consume and further enhancing fire activity. This study provides policymakers with key information regarding how the effects of one global crisis — climate change — can have cascading effects on concurrent global crises — in this case, the COVID-19 pandemic,” she said.
The also highlights on its website that recent scientific publications suggest that air pollution exposure worsens coronavirus symptoms and outcomes.
PM 2.5, or particulate matter measuring 2.5 micrometers across, can irritate lungs, cause inflammation, alter immune function and increase susceptibility to respiratory infections. Smoke exposure is linked to both long-term and short-term health issues, including decreased , weakened immune systems, higher rates of flu, and even hospitalizations and death.
According to the CDC, people with asthma, chronic obstructive pulmonary disease (COPD), , and children are especially at risk, as symptoms can include trouble breathing, wheezing, coughing, asthma attacks, stinging eyes, scratchy throat, runny nose, irritated sinuses, headaches, fatigue, chest pain and increased heart rate.
People in fire zones or areas where smoke drift is likely are advised to create clean living environments, shelter in a cleaner air shelter or cleaner air space if the at home cannot be kept sufficiently clean and wear a fit-tested, NIOSH-approved N95 or P100 respirator, consults local guidelines and monitor the EPA’s (AQI) forecasts and other resources.
Researchers are currently looking into whether PM 2.5 is a potential coronavirus carrier.
Julia Musto is a reporter for Fox News Digital. You can find her on Twitter at @JuliaElenaMusto.