SAN FRANCISCO (CBS SF) — While the smoke from the many fires burning in Northern California is unpleasant for local residents,  in the era of COVID-19, it can lead to some serious health risks.

The Bay Area has been under a Spare the Air alert since Tuesday. The current alert has been extended through Sunday due to the fires raging across the region.

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“It’s really become the new normal that we have these megafires that foul our air,” said Dr. John Balmes, a UCSF Professor of Medicine with a focus on occupational and environmental medicine as well as pulmonary and critical care. 

Several UCSF doctors laid out some of the dangers presented by wildfire smoke.

Healthy people will experience things like eye, nose, throat and airway irritation. But for people with respiratory conditions like asthma and COPD and those with heart disease, it’s even worse.

“The immune response is altered by air pollution exposure,” explained Dr. Balmes.

UCSF Assistant Professor of Medicine Dr. Stephanie Christenson said the particles are tiny but damaging.

“They’re about 20-30 times smaller than the diameter of a follicle of hair; very, very small,” said Dr. Christenson. “And they can get in an lodged deeply in the lung and cause inflammation.”

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Currently, doctors are not positive the smoke can make people more susceptible to COVID-19 or worsen symptoms, but some studies do make an association.

“If you’ve already got worse symptoms from your COVID-19 — more cough, more shortness of breath — and now we’ve given you another insult, that could make matters worse,” said Dr. Christenson.

High-risk individuals are advised to stay indoors if possible to protect themselves.

“Keeping the windows closed, having good ventilation, closed ventilation,” said Dr. Christenson. “An air purifier if you can swing it.”

Unfortunately, the wearing of facial covering as required in public by the pandemic wont do much good as far a smoke.

“The regular cloth masks probably do very little to protect you from wildfire smoke exposure,” said UCSF Associate Professor of Emergency Medicine Dr. Jahan Fahimi. “But certainly they will mitigate the transmission of COVID-19, so there’s definitely some benefit there. “

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Resources to track the air quality in the Bay Area are available online at the Bay Area Air Quality Management District website and the EPA’s Air Now website.