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As wildfire season ramps up across the western U.S., there are new fears in a year that is like no other. Smoke from burning forests that often spreads across wide areas could make people more susceptible to coronavirus infections and make those infections more deadly. Montana Public Radio's Aaron Bolton looks at what is and isn't known.
AARON BOLTON, BYLINE: Wildfire smoke has long been a public health concern in Montana. In 2017, emergency room visits for breathing problems more than doubled in a pair of counties where huge fires were burning out of control. The smoke was so bad in the town of Seeley Lake that the local health department told everyone to evacuate. But not everyone can afford to leave.
AMY CILIMBURG: So this is a basic fan, right? Just got this from the local hardware store. It cost $17, not too much money.
BOLTON: Amy Cilimburg with the environmental nonprofit Climate Smart Missoula is filming a video in her backyard demonstrating how to make a portable air cleaner for under $45 using a furnace filter.
CILIMBURG: And you can also, at the hardware store, buy a filter.
BOLTON: The box-fan filter combo is drastically cheaper than the high-efficiency air or HEPA filters that sell for anywhere from 100 to a thousand dollars. Cilimburg says a filter with a high enough rating can be connected to the back of a fan with tape or a bungee cord and placed in the middle of a closed-off room to filter out tiny particles called PM 2.5, which are known to cause a myriad of health issues.
Cilimburg and local public health officials say affordable options to clean indoor air are especially important this fire season with coronavirus infections on the rise. But because the virus is so new, the slow, careful science necessary to confirm or disprove a link between wildfire smoke and bad outcomes isn't in yet. Still, Dr. John Balmes, a researcher at the University of California, says...
JOHN BALMES: There is already fairly good evidence from China, Italy and one important study in the U.S. to suggest that people that are infected with the virus who are exposed to fine particulate pollution have increased risk of severe COVID-19 and death. That evidence is looking more and more robust.
BOLTON: Balmes points to preliminary research coming out of Harvard that suggests even small increases in particulate pollution is associated with an 8% increase in COVID-19 deaths. Another study out of Montana found a significant increase in flu virus infections in people who'd been through a smoky wildfire season. The health risks are of particular concern to wildland firefighters, who often convene by the hundreds in firefighting camps every summer.
Mike DeGrosky with Montana's Department of Natural Resources says the so-called camp crud - coughing and respiratory problems - is common in the temporary tent cities every summer.
MIKE DEGROSKY: Large fire camps - yeah, we're going to really have to pay attention to how we feed people, how we social distance, changing where people sleep, changing how we serve food.
BOLTON: This year, fire agencies are trying not to have big fire camps and to minimize close physical contact among firefighters. But there's no way to keep them from breathing in a lot of smoke on the job.
For NPR News, I'm Aaron Bolton reporting from Columbia Falls, Mont.
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