Warnings that wildfire smoke exacerbates Covid risk as study finds firefighters left with permanent lung damage from being on frontlines

The researchers found that coronavirus cases increased during the 2020 wildfire season

A National Oceanic and Atmospheric Administration map showing vertically integrated smoke originating from wildfires wafting over the central and eastern US. (National Oceanic and Atmospheric Administration)

If battling massive walls of flame was not enough of an occupational hazard for firefighters, a group of scientists in Nevada have released a study suggesting individuals exposed to wildfire smoke for long periods of time are at greater risk of contracting the coronavirus.

Scientists at the Desert Research Institute in Nevada published the study last week, and found that coronavirus infection rates rose at a disproportionate rate during the 2020 wildfire season. They concluded that the wildfire smoke wafting into other states made people more susceptible to the coronavirus.

The research was published in the Journal of Exposure Science & Environmental Epidemiology, and pointed out that positive coronavirus cases rose in Washoe County, Nevada during periods when monitoring stations reported high levels of wildfire smoke-related particulate matter in the air.

Daniel Kiser, an assistant research scientist at the institute and one of the five authors of the study, allowed that the rise in cases could be attributed to other issues, such as the second surge of coronavirus cases last year or students returning to school, which coincided with the latter half of the wildfire season. Regardless, he argued that the correlation did suggest some connection between increased smoke exposure and increased risk of contracting the coronavirus.

The study showed that for every ten micrograms per cubic meter of small particulate matter in the air, the rate of positive coronavirus cases rose about 6.3 per cent between two and six days later.

According to the research, the type of particulate matter – called PM2.5 – suggests the source of the uptick is not from other matter, like vehicle traffic or industrial pollutants.

Speaking with the Associated Press, he said the "temporary association in the midst of a large uptick in cases overall is what convinced us that somethings going on”.

While the increased small particulate can put anyone in the proximity of the fires at risk, another study, published by the University of Alberta Faculty of Medicine & Dentistry in Science Daily, found that exposure to the smoke has caused extensive lung damage in firefighters tasked with battling the blazes.

The study specifically looked at firefighters who battled the 2016 Fort McMurray wildfire in Alberta, finding that they suffered persistent lung damage as a result.

Individuals with damaged lungs have a more difficult time fighting off the effects of the coronavirus.

Mr Kiser suggested that the impacts of wildfires on the environment and on humans would likely play a role in virus research in coming years.

Numerous places across the US, including eastern states on the opposite side of the country from the fires, reported hazy skies over the past week as a result of wafting smoke from the blazes.