Wildfire Smoke's Hidden Toll on Patients with Allergies

Allergists are documenting a wildfire health effect that extends well past the smoky week that makes headlines.

Most wildfire smoke research centers on its cardiopulmonary effects, with fine particulate matter linked to asthma flare-ups, heart attacks, and strokes. California studies tied children's smoke exposure to more coughing, wheezing, bronchitis, colds, and asthma-related doctor or hospital visits. Wildfires also release carbon monoxide, and inhaling it limits oxygen delivery to the body's organs and tissues, causing headaches, nausea, and dizziness, and at high levels, death.

The Link Between Wildfire Smoke & Allergies

However, little research focuses on the link between wildfire smoke and allergies.

An observational study published in 2022 reported that patients at a local allergy clinic in northeastern North Carolina showed measurable declines in lung function a full year after exposure to wildfire smoke from 2 peat bog fires (2008 and 2011) in the Great Dismal Swamp. Investigators reviewed 5 years of clinical records for 842 patients with allergic rhinitis and/or asthma, using peak flow measurements and wind direction as a proxy for smoke exposure, and found that deficits were consistently worse one year after the fires than during them.¹

For every 1 percent increase in time the wind blew from the fire toward the community, peak flow dropped by an average of 2.21 liters per minute, with the steepest declines seen in women, Black patients, and under strong wind conditions. These findings held up even after adjusting for age, sex, race, and BMI, suggesting the smoke exposure itself, not just demographic factors, was driving the delayed drop in lung function. The authors proposed that wildfire smoke may act as an adjuvant, heightening patients' allergic sensitivity or triggering a delayed immune response that doesn't surface until months later.¹

"We didn't see anything initially during the actual wildfire or immediately thereafter," said investigator Jim Blando, PhD, chair of the Department of Epidemiology, Biostatistics, and Environmental Health at Old Dominion University, in an interview with HCPLive.

Blando compares the pattern to how the body responds to poison ivy: the first exposure may not trigger a reaction, but repeated exposure builds sensitization. He also points to climate change more broadly, noting longer growing seasons and earlier pollen production are compounding the problem alongside wildfire smoke.

At Massachusetts General Hospital, Wynne Armand, MD, has watched a related pattern unfold in dermatology records.² Eczema flare visits spiked sharply during recent wildfire seasons, tracking closely with air pollution severity. Armand explains patients with eczema already have a weakened skin barrier, making it easier for smoke particles to trigger a stronger immune response.

Both experts caution the underlying science is still developing. Armand said understanding wildfire smoke's specific contribution to allergic disease, not just symptom flares, “will be a very critical piece” of future research.

In the meantime, both recommend a mix of monitoring air quality, minimizing outdoor exposure during smoke events, wearing a properly fitted N95 respirator, and for skin protection, using mineral-based sunscreen and rinsing exposed skin after being outdoors.

“I personally feel pretty confident that as we look into it further, we are going to find a lot of evidence supporting that wildfire smoke is very allergenic,” Blando said.

References

1. Blando J, Allen M, Galadima H, Tolson T, Akpinar-Elci M, Szklo-Coxe M. Observations of Delayed Changes in Respiratory Function among Allergy Clinic Patients Exposed to Wildfire Smoke. Int J Environ Res Public Health. 2022 Jan 22;19(3):1241. doi: 10.3390/ijerph19031241. PMID: 35162264; PMCID: PMC8835059.

2. Armand W. One surprising effect of wildfires: Itchy, irritated skin. Harvard Health Publishing. June 24, 2024. Accessed September 9, 2026. https://www.health.harvard.edu/blog/one-surprising-effect-of-wildfires-itchy-irritated-skin-202406243052