Wildfire smoke linked to 17% increase in Covid cases

Exposure to wildfire smoke is linked to an increased risk of contracting Covid-19, according to a study published in the Journal of Exposure Science and Environmental Epidemiology. 

The research team from the Desert Research Institute used models to analyse the relationship between exposure to particulate matter (PM2.5) from wildfire smoke in the Western U.S and Covid-19 positivity rate data from Renown Health. 

According to their results, exposure to PM2.5 from wildfire smoke was responsible for a 17.7% increase in the number of Covid-19 cases that occurred during a period of prolonged smoke. 

Reno, located in Washoe County in northern Nevada, was exposed to higher concentrations of PM2.5 for longer periods of time in 2020 compared to other nearby metropolitan areas. 

Gai Elhanan, co-lead author of the study said: ‘We had a unique situation here in Reno last year where we were exposed to wildfire smoke more often than many other areas, including the Bay Area.

‘Our results showed a substantial increase in the Covid-19 positivity rate in Reno during a time when we were affected by heavy wildfire smoke from California wildfires.

‘This is important to be aware of as we are already confronting heavy wildfire smoke from the Beckwourth Complex fire and with Covid-19 cases again rising in Nevada and other parts of the Western U.S.’

This research builds upon past work of studies in San Francisco and Orange County by controlling for additional variables such as the general prevalence of the virus, air temperature, and the number of tests administered, in a location that was heavily impacted by wildfire smoke.

‘We believe that our study greatly strengthens the evidence that wildfire smoke can enhance the spread of Covid-19,’ said Elhanan.

‘We would love public health officials across the U.S. to be a lot more aware of this because there are things we can do in terms of public preparedness in the community to allow people to escape smoke during wildfire events.’

Photo by Marcus Kauffman