As wildfires continue burning across Southern California, medical experts are warning that smoke inhalation can weaken the immune system and make people more vulnerable to respiratory infections, including the novel coronavirus.
The Centers for Disease Control says wildfire smoke can irritate the lungs, cause inflammation, and make a person more prone to lung infections, including SARS-CoV-2, the virus that causes COVID-19. In Southern California, the South Coast Air Quality Management District has issued unhealthy to hazardous air quality alerts and smoke advisories in San Bernardino, Riverside, Orange, and Los Angeles counties.
Hospitals across the state already have seen an increase in emergency room visits and admissions from patients experiencing exacerbation of asthma symptoms due to smoke exposure, said Dr. Thomas Yadegar, a pulmonologist at Providence Cedars-Sinai Tarzana Medical Center.
Yadegar said he has treated more than a dozen patients since the wildfires began.
“Every single one of them said their breathing has been worse … and they’re using their rescue inhalers more often,” he said. “In our patient population, we are definitely getting a lot more calls and dealing with a lot more patients.”
Doctors also are concerned about the upcoming flu season and how much COVID-19, and now the wildfires, will tax hospitals, doctors and resources.
“This is not very typical. We usually start seeing more patients with asthma exacerbation in the fall, during cold and flu season, and in the springtime it’s usually due to allergies and the winds, but this year, with all the wildfires, I think it’s the reason we’re seeing increased activity,” Yadegar said.
Even short-term smoke exposure hinders the human body’s ability to fight off infection, said Dr. Richard Huynh, a pulmonologist at Torrance Memorial Medical Center.
“I have seen a sharp rise in patients in my practice suffering from respiratory problems/exacerbations over the past few weeks due to the wildfires,” Huynh said.
Riverside University Health System Medical Center also has seen a slight increase in ICU admissions for patients with chronic obstructive pulmonary disease who are suffering exacerbated conditions due to smoke inhalation, said Dr. Destry Washburn, a pulmonologist at the hospital.
He anticipates more admissions and patient appointments for such reasons.
“It would definitely be expected. Historically, we often see an increase in ER visits and hospital admissions that are respiratory related during wildfire season,” Washburn said.
Smoke and COVID-19
While people with preexisting health conditions such as asthma, COPD and emphysema already are at higher risk of contracting COVID-19, they are even more susceptible now due to exposure to unhealthy or hazardous air from the fires, according to medical experts.
Tiny, microscopic particulates from smoke inflame and dry up the mucous membranes lining the body’s airways, making it more difficult to fight off infection and making someone more susceptible to the novel coronavirus, according to medical experts.
“COVID is a viral pathogen, so you become more vulnerable (to COVID-19) because your airways are not at 100 percent in terms of how they normally function to protect themselves,” said Dr. Raymond J. Casciari, a pulmonologist at St. Joseph Hospital in Orange. “Fire tends to dry people out, and when people are dry they don’t produce as much mucous … the airways and membranes become irritated, swell, and crack and become more vulnerable to any pathogen that’s in the area.”
He said worst-case scenarios are respiratory failure, pulmonary inflammation and pulmonary fibrosis, which is scarring of the lungs that results in a lack of oxygen, making it difficult to breathe.
What studies show
Studies show a nexus between air pollution and an increased risk of developing or dying from the novel coronavirus.
A recently published analysis of nine COVID-19 and SARS studies concluded that there were “positive associations” between air pollution and COVID-19 infections and death rates.
“It is plausible that both daily increases and chronic, historical exposures to outdoor air pollution adversely impact prognoses among those with SARS or COVID-19,” according to the study.
Another study published in March found a link between air pollution in Lombardy and Emilia-Romagna in Northern Italy — among Europe’s most polluted areas — and COVID-19 lethality. It concluded that people living in highly polluted areas are more prone to develop chronic respiratory conditions.
Researchers at Harvard T.H. Chan School of Public Health concluded in an April study that a small increase in long-term exposure to the pollutant PM2.5 — inhalable airborne particles measuring 2.5 micrometers in diameter or smaller — leads to a large increase in the COVID-19 death rate.
Medical and public health officials, however, caution that the studies are new, and many have not been through the peer-review process.
Health care professionals recommend people stay indoors as much as possible until air quality improves, avoid exercise and/or overexerting themselves, and continue wearing face coverings, preferably N95 masks.
Additionally, people should continue COVID-19 best practices including regular hand washing and social distancing. People should also keep all their doors and windows shut and use their home and vehicle air conditioners often. When using air conditioners, they should be set to recirculate existing air in homes and vehicles. HEPA air conditioner filters should be used in homes and replaced often.
Symptoms of overexposure to toxic air are burning eyes and lungs, which is an indicator to get inside as quickly as possible.
“If your eyes start to burn, that means your lungs are burning and you need to get indoors and take a break,” Casciari said. He said face coverings should have two straps to better secure the mask to the face.
Huynh, the pulmonologist at Torrance Memorial, said the website Airnow.gov provides air quality indexes and risk factors, based on ZIP code. “You can dictate from that whether you want to go outside or not,” he said.
Firefighters at highest risk
People with preexisting health conditions are not the only ones at highest risk for respiratory infections and COVID-19 due to wildfires. Those on the front lines battling the blazes, the firefighters themselves, are at highest risk, according to medical experts.
“They’re definitely at the highest risk, having the highest amount of (smoke particulates) enter into their lungs,” said Washburn, the pulmonologist at Riverside University Health System Medical Center. “They are going to be at highest risk for these kinds of alterations to their immune systems. There’s a lot of concern there.”
Casciari, the pulmonologist at St. Joseph Hospital in Orange, said, “In a fire, the entire (respiratory) system begins to break down. Firefighters have nowhere to go. They have to protect themselves the best they can.”
CalFire spokeswoman Lynne Tolmachoff said there have been days when smoke from the wildfires has been so thick firefighters could not see more than 100 to 200 feet in front of them. “It’s been absolutely horrible,” Tolmachoff said of the conditions.
Firefighters are being cautioned to stay hydrated, well fed, socially distance and to wear their helmet shrouds and face coverings as needed. Respirators, Tolmachoff said, are typically used on structure fires, not wildfires, are heavy and cumbersome, and only hold enough oxygen to last 30 minutes.
Firefighters are working 24-hour rotations — working 24 hours straight and then taking 24 hours off for rest, Tolmachoff said.
Safety protocols have been similar with other fire agencies.
San Bernardino County firefighters assisting on the 18,000-plus-acre El Dorado Fire in the mountains above Yucaipa also are adhering to social distancing, mask wearing and hand-washing guidelines. Trailers and portable toilets at base camp are being cleaned regularly throughout the day, and extra precautions are being made in meal distribution to firefighters, agency spokeswoman Tracey Martinez said.
Firefighters are required to wear face coverings while riding in engines en route to the fire lines and while at base camp, where disposable masks are provided, Martinez said.
“It’s in every incident action plan, and they talk about it at every briefing,” Martinez said of the COVID-19 protocols and standards for firefighters. She said strike team and division leaders also go over the COVID-19 restrictions and guidelines during twice-daily briefings.
Steve Rasmussen, spokesman for California Incident Management Team 11 that is managing the El Dorado Fire in San Bernardino County, said engine, bulldozer and hand crews are social distancing by isolating from other crews while battling the fire and cutting line around it to contain it.
“In camp we’re doing temperature checks day and night, and supervisors are checking for any type of COVID symptoms on the front lines,” Rasmussen said. “If someone tests positive, we determine where they were working and who was closest to them so we can do whatever we can to prevent the spread of COVID-19.”
So far, Rasmussen said, no firefighter has tested positive for COVID-19 or had to be removed from the fire lines due to illness.