Wildfire smoke poses a growing threat to respiratory health across the entire United States, with smoke traveling up to 2,100 miles from its source and affecting regions 10 to 15 times larger than the actual burn area. As climate change intensifies wildfires in frequency, duration, and severity, pulmonologists are taking proactive steps to prepare their practices and patients for what experts warn could be a particularly dangerous season ahead .

Why Is Wildfire Smoke More Dangerous Than Regular Air Pollution?

Wildfire smoke is not the same as typical outdoor air pollution. It contains a toxic mixture of carbon monoxide, volatile organic compounds, and nitrous oxide, along with at least 20 hazardous air pollutants recognized by the Environmental Protection Agency (EPA). This unique composition causes lung injury through multiple mechanisms: it damages the airway lining, triggers inflammation, creates oxidative stress, and increases susceptibility to infection .

The health consequences are serious and measurable. Research shows strong links between wildfire smoke exposure and asthma exacerbations, as well as significant associations with chronic obstructive pulmonary disease (COPD) exacerbations. Beyond these conditions, higher particulate matter days correlate with increases in all-cause deaths, cardiovascular deaths, and respiratory deaths .

"Wildfire smoke can spread much further than the actual fire and can impact a region 10 to 15 times larger than the burn area. The fine particulate matter in wildfire smoke disperses over a large area and settles slowly, thereby potentially impacting a large region over a prolonged exposure time," said May-Lin Wilgus, MD, pulmonologist and assistant clinical professor at the University of California, Los Angeles.

May-Lin Wilgus, MD, Pulmonologist and Assistant Clinical Professor at University of California, Los Angeles

Who Is Most Vulnerable to Wildfire Smoke?

While everyone faces some risk from wildfire smoke exposure, certain populations are significantly more vulnerable. These include people with asthma, people with COPD, pregnant women, infants, children, older adults, and firefighters. However, experts emphasize that no one is completely exempt from the threat. Exposure can provoke symptoms and increase the risk for asthma even in previously healthy individuals .

The geographic reach of this threat is expanding rapidly. Historically, wildfires mainly affected California, but recent years have brought smoke-related health concerns to much broader portions of the country. A 2024 study found that wildfires originating in Western Canada increased the cardiopulmonary burden in Maryland, which is 2,100 miles away. This year is shaping up to be particularly dire, with wildfires already appearing in unusual areas such as Nebraska, fueled by record-breaking warm temperatures in March and drought conditions affecting more than half of the country .

How to Prepare Your Practice and Patients for Wildfire Season

Pulmonologists are implementing comprehensive preparation strategies at both the community and individual patient levels. Here are the key steps clinicians are taking:

• Identify High-Risk Populations: Review data from registries on symptoms, prescription patterns, healthcare utilization, language, and ethnicity to identify high-risk individuals such as those with COPD or asthma, agricultural workers, and non-English speaking people who may need special education on safety.
• Establish Multidisciplinary Care Teams: Create teams that may include primary care and pulmonary physicians, nurses, therapists, and community health workers to provide customized interventions tailored to community needs.
• Provide Practical Support: Offer high-risk patients transportation, supplies, education, and quality air filtration to help them manage smoke exposure effectively.
• Refill Medications Early: Provide prescriptions for early inhaler refills and nebulizer medications so patients have adequate supplies before smoke season intensifies.
• Update Action Plans: Review and update COPD and asthma action plans so patients know exactly how to respond to symptoms during periods of prolonged smoke exposure.
• Personalize Respirator Recommendations: Offer personalized recommendations about whether N95 respirators are indicated and provide instruction on proper use, since these devices can increase breathing difficulty in people with heart or lung disease.

Beyond clinical interventions, pulmonologists are educating patients on practical smoke precautions. A critical area involves monitoring the Air Quality Index (AQI) and understanding what different levels mean for daily activities. According to pulmonology experts, an AQI higher than 101 is unhealthy for sensitive populations, an AQI higher than 151 is unhealthy for the general population, and an AQI higher than 301 is extremely hazardous to everyone .

"In general, an AQI higher than 101 is unhealthy for sensitive populations, an AQI higher than 151 is unhealthy for the general population, and an AQI higher than 301 is extremely hazardous to the general population," explained Ashraf Elsayegh, MD, pulmonologist and critical care medicine specialist at Providence Saint John's Health Center in Santa Monica, California.

Ashraf Elsayegh, MD, Pulmonologist and Critical Care Medicine Specialist at Providence Saint John's Health Center

What Should Patients Do on High-Smoke Days?

Practical guidance for patients during wildfire season includes several evidence-based strategies. On poor air quality days, patients should limit outdoor exposure, abstain from outdoor exercise and activities, or remain indoors entirely. Patients should gather an emergency kit that includes medications such as nebulizers and stock up on groceries and other supplies to avoid the necessity of going out on smoky days. When shopping, patients should prioritize groceries that do not require refrigeration or cooking, since some forms of food preparation generate indoor air pollution .

At home, patients should find out how to close the fresh-air intake in their home central air system and refrain from using candles, aerosols, and tobacco products, all of which increase indoor air pollution. If evacuation is not necessary, patients should prepare at least one room in the home to keep out wildfire smoke by closing off sources of outside air and setting up an air purifier with a HEPA (high-efficiency particulate air) filter. After fires are put out, people with heart or lung disease should avoid cleaning areas containing soot or dust, as this can cause additional respiratory damage .

What Are the Warning Signs of Smoke Exposure?

Clinicians are watching for both acute and long-term signs of wildfire smoke exposure. Acute symptoms include irritation of the throat, nose, and eyes, along with cough, breathlessness, or headache. Short-term effects also include a higher incidence of infections, especially pneumonia and bronchitis. Additionally, people with chronic respiratory disease may experience a loss of control over their symptoms and use an inhaler more frequently, which leads to increased visits to the emergency department .

Long-term effects involve declines in pulmonary function, which may manifest in reductions in peak expiratory flow, forced expiratory volume, and the ratio of forced expiratory volume to forced vital capacity. While pulmonary function in firefighters typically declines temporarily after battling a large fire and is usually reversible after some time, longer exposure increases the likelihood of more permanent damage. Exposure to particles from urban fires makes permanent lung damage even more likely .

As wildfire season approaches, the message from pulmonologists is clear: preparation, prevention, and early detection are essential. With smoke now capable of traveling thousands of miles and affecting regions far beyond the initial fire, respiratory health has become a nationwide concern requiring coordinated action from healthcare providers and informed patients alike.