Allergies and Asthma: Insights on Climate and Health

Mar 29, 2016 | News

Mounting evidence has been demonstrating the threats climate change poses to human health in the United States, particularly for vulnerable populations such as young children, the elderly, those living in poverty, and those whose health is already compromised by chronic conditions.  The most apparent and widespread impacts to human health at this time affect the respiratory system with increased exacerbations of asthma, allergies and other chronic and acute lung conditions.  The consensus across scientific studies shows that increased anthropogenic emissions of carbon dioxide contributes to the formation of ground level ozone often visible as smog and increases allergenic pollen production.  Both can be triggers of asthma attacks and/or worsening allergy symptoms among the approximately 50 million adults and children nationwide who are affected by seasonal allergic rhinitis and 25 million affected by asthma.

Surveys collect physicians’ views on climate change

To the extent that adaptation will be necessary to reduce the harmful health effects of climate change, a greater understanding about the beliefs, attitudes, and experiences of clinical practitioners on the front lines of medical care are of great public health interest. In collaboration with a research center at George Mason University, the American Academy of Allergy Asthma and Immunology (AAAAI) surveyed the members to investigate these topics.  Over 90% of the 1184 respondents were medical doctors (the remaining holding PhDs, masters and/or other clinical degrees).  They provided their perceptions and clinical experiences of the health impacts from climate change, as well as what actions they believe should be taken to reduce the associated health risks.1

Doctors are witnessing medical problems caused by climate change among their patients

Not only did the majority of respondents (83%) indicate that climate change has relevance to direct patient care, but most (74%) also reported that climate change is already affecting their patients’ current health.

When asked, “Do you think your patients are currently being affected by climate change, or might be affected in the next 10-20 years?” the most common responses were that their patients are being affected by air pollution-related increases in severity of chronic disease, such as asthma, COPD, pneumonia, cardiovascular disease, and increased care for allergic sensitization and symptoms of exposure to plants or mold (visits to the office/ER for asthma/allergic symptoms).

Many respondents provided relevant anecdotes about patients who have experienced climate change related health impacts. One doctor from Florida remarked that tree pollen season is starting three weeks earlier, and his patient’s seasonal allergy symptoms are more severe and last longer.  A doctor from Michigan reported seeing numerous patients with fall mold allergies whose symptoms now last well into December because the ground takes longer to freeze. A Texas physician described a patient who previously had seasonal allergy symptoms to grass but now has year-round symptoms because of the overall warmer climate and extension of grass season.  A DC allergist described, “A combination of high automobile pollution in Washington, DC metro area with heat, humidity and high pollen [that] produced not only nasal allergy and wheezing, but also very severe redness and itchy eye irritation in August.”  These accounts are consistent with the medical and environmental health literature in terms of how the changing climate may be affecting human health in the U.S.

Physician leadership on environmental sustainability, advocacy and education

In their responses to actions that should be taken, a majority of respondents (70%) indicated that physicians should have a leadership role in encouraging offices, clinics, and hospitals to be as environmentally sustainable as possible. There was also a considerable amount of support for education on climate change and health in the form of continuing medical education, undergraduate medical education, and patient education materials. The majority of respondents agreed that the physicians should have a significant advocacy role, as well as a responsibility to bring the health effects of climate change to the attention of the public. These findings were entirely consistent with the results of two prior physician surveys of other medical societies, namely the National Medical Association and the American Thoracic Society.

Many respondents indicated that they are interested in playing a larger role on climate change and environmental sustainability, and they support leadership by physicians and their professional societies. As an extension of the survey, 85 physicians from AAAAI requested further involvement and opportunities in the areas of education, outreach and advocacy.

A Call for Action!

Although much work needs to be done in the area of climate and health, results from the physician surveys are encouraging.2,3 Medical doctors are highly trusted sources of information, specifically about climate change and, thus, have great opportunities for educating the public.4 According to a 2014 Gallup poll, 65% of Americans rated medical doctors as having very high honesty and ethical standards.5 Given that physicians are trusted leaders in our society, some view their participation in climate change as a moral and social responsibility. As more medical practitioners become more informed about the health effects of climate change, participate in sustainability efforts, educate their patients in prevention and adaptation strategies, and advocate for a healthier planet, our collective prognosis becomes more hopeful.

Opportunities and Resources:

Presentations and education materials:

For presentation slides and talking points designed for educating the public on climate, please contact George Mason University Program on Climate and Health of the Center for Climate Change Communication.  Contact Dr. Mona Sarfaty at [email protected]

Websites and downloadable apps for measuring ambient particulate matter and pollen:

American Academy of Allergy, Asthma & Immunology

Pollen & Spore Levels:

Allergy Pollen Count (Android app):

Interactive map:

Allergy forecast page:

State of the Air – By American Lung Association

Apple app:

Android app:

Air Now:

App (Platform: Apple, Android, Web):



  1. Sarfaty M, Kreslake J, Casale T, Maibach E. Views of AAAAI members on climate change and health. Journal of Allergy and Clinical Immunology-In Practice. Published online December 16, 2015.
  2. Sarfaty, M., Bloodhart, B., Ewart, G., Thurston, G. D., Balmes, J. R., Guidotti, T. L., & Maibach, E. W. (2015). American Thoracic Society member survey on climate change and health. Annals of the American Thoracic Society, 12(2), 274–278.
  3. Sarfaty, M., Mitchell, M., Bloodhart, B., & Maibach, E. (2014). A survey of African American physicians on the health effects of climate change. International Journal of Environmental Research and Public Health, 11(12), 12473–12485.
  4. Climate Change in the American Mind. March 2015. Page 26.
  5. Gallup Poll 2014 on Trusted Professions.