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Doctors have said that fresh air can reduce the spread of the coronavirus — but when that air is polluted, such as during wildfire season, people may be more likely to catch COVID-19 and have more severe cases, a Utah pulmonologist warned.
“One tricky thing is that being outside has been generally safer for COVID-19 transmission,” Dr. Cheryl Pirozzi, a pulmonologist at University of Utah Health, told reporters in a videoconference briefing Monday. “But if we’re in a condition of elevated air pollution due to wildfire smoke, then that’s no longer the safest place to be.”
Recent research, Pirozzi said, shows that particulates in air pollution, including wildfire smoke, “can increase the risk for COVID-19 infection, and more severe disease or deaths due to COVID-19.”
Utah suffered through bouts of hazy days in August, much of it caused by wildfire smoke that blew in from California. Pirozzi said it’s possible more smoke is on the way.
“Because of climate change and warmer and drier conditions in the West,” Pirozzi explained, “wildfires are expected to continue to become more frequent and more severe.”
U. Health and Intermountain Healthcare have collaborated on research about the medical effects of short-term spikes in air pollution in Utah, said Dr. Denitza Blagev, a pulmonologist at Intermountain.
Studies have found an increase in hospitalizations for various respiratory diseases — such as bronchitis or pneumonia — when the level of particulates goes up, Blagev said. There isn’t enough data yet in Utah to determine whether the same increase happens with COVID-19.
Particulates can damage the lining of the lungs, breaking down the lungs’ defenses against infection, Pirozzi explained. Pollution can also affect the immune system, she said, and cause inflammation that leads to diseases becoming more severe.
A “well-fitting” medical-grade N95 mask can filter out particulates, Pirozzi said. However, she added, cloth and surgical masks — the sort many people are wearing, particularly in places where they are mandated — can keep droplets from going out, but can’t keep the tinier particulates from being breathed in.
The elderly and people in high-risk groups, Pirozzi said, should avoid outdoor activity during bad air days. Those people and their loved ones should work to make their indoor surroundings “a clean air space,” such as using a HEPA filter, she said.
“Indoor air tends to be cleaner than outdoor air, and you’re getting more air pollution exposure when you exercise,” Blagev said. During times of poor air quality, she said, people should exercise indoors when they can, or go outdoors during times of day when the particulate count is lower.
At University of Utah Hospital, the number of symptomatic patients seeking COVID-19 testing went down from July 5 to Aug. 10, then was relatively stable through August, said Dr. Russell Vinik, chief medical operations officer at U. Health.
The number of respiratory patients being treated at the hospital’s emergency department has been mostly stable for the past six weeks, Vinik said.
If someone has severe respiratory symptoms, from either COVID-19 or pollution, Vinik said, that person should get to an emergency room — and not worry about catching the coronavirus.
“Coming to the hospital is safe,” Vinik said.
Those with less severe symptoms, he added, should call their doctor or arrange a telehealth visit.