Wildfire smoke particles may increase risk of COVID and death

OAKLAND, Calif. - Air quality and disease researchers say data suggests wildfire smoke can increase the spread of COVID-19 and other infections if precautions are not taken.

Exposure to fine pollution particles in smoke may have already led to thousands of cases and deaths, according to new research from Harvard University.

The published study concluded roughly 20% of the coronavirus cases in some California and Washington counties last year were linked to high levels of wildfire smoke.

Breathing in that smoke can cause small particles to get into the lungs and enter the blood stream.

Harvard biostatistics professor Francesca Dominici said that has a negative effect on the immune system making it harder to fight off any kind of virus.

"You’re breathing these particles and they’re already making you sicker to begin with," Dominci said. "Then you’re getting the virus on top so your ability to fight the virus is compromised. There’s a high risk of death."

She said it’s a an even bigger concern for vulnerable populations, especially those who work outdoors. Farmworkers, those with respiratory conditions, children and the unvaccinated are most at risk.

The U.S. Centers for Disease Control and Prevention even says wildfire smoke can irritate lungs and cause infections, including COVID-19.

"With the delta variant it’s already very contagious," Dominici said. "Whether vaccinated or unvaccinated, exposure to wildfire smoke is something that really has to be prevented as much as possible."

She is pushing people to get vaccinated immediately to avoid contracting the virus.

Scientists who study air quality say the coronavirus may even be carried by those smoke particles, potentially leading to more infections.

University of California Davis environmental epidemiologist Irva Hertz-Piccotto agrees.

"More particles in the air is more vectors to transmit from one person to another," she said. "We think that’s part of why sometimes we have more viruses in general in the wintertime because you do tend to have more particle pollution."

Hertz-Piccotto suggests staying indoors, keeping windows shut, and investing in air purifiers to reduce the risk of breathing toxic air.

Already, she said there are indications of a link between respiratory issues caused by smoke and mental health. Early signs point to more people suffering from anxiety or depression.

"There may be this kind of synergism happening," Hertz Piccoto said. "We’re all in this together and we really need to come together to come up with the best solutions."

Brooks Jarosz is an investigative reporter for KTVU. Email him at brooks.jarosz@fox.com and follow him on Facebook and Twitter: @BrooksKTVU