MINNEAPOLIS/ST. PAUL (04/10/2023) — Climate change causes more extreme winter weather, wetter springs and hotter summers in the United States. Ahead of Earth Day on April 22, Emily Onello, MD, and Joseph Bianco, MD, with the University of Minnesota Medical School talk about how climate change impacts human health.

Q: What are some of the ways that climate change can show up in our day-to-day lives that impacts our health? 
Dr. Bianco:
Much of the world’s population works outside. For those who labor under the sun, the earth’s warming puts them at increased risk for heat-related illnesses. This can lead to less time to farm or harvest as well as reduced yields. Further, less yields of crops can change the economics of food and pricing, leading to certain foods being more expensive and beyond the reach of many.  
Another impact is the increasing frequency of severe weather events across the country. Floods, tornadoes and wildfires affect many aspects of daily life, from increased economic hardships to the catastrophic loss of life.

Q: How does climate change impact allergies? 
Dr. Onello:
Studies have shown that the resulting warming from climate change is a significant factor leading to longer allergy seasons. Pollen season now starts 20 days earlier and lasts 10 days longer. There’s also an increased amount of plant pollen circulating during allergy season. For people with environmental allergies or allergy-induced asthma, this means a longer duration of allergy symptoms as well as the need to take medication on more days of the year.

There are also indirect effects of climate change to consider. For example, severe weather events with flooding can result in damp buildings and potential for increased mold spore exposures, which in turn increases allergic reactions and symptoms. Climate change also alters existing patterns of wind, rain and storm activity. Such alterations further impact the airborne path and dispersion of pollen and other allergens — potentially creating new geographic “hot spots” for allergy sufferers. 

Q: How does climate change impact tick-borne disease? 
Dr. Bianco:
The range for survival of certain ticks has expanded. In the past, cold winters have curtailed the prevalence of certain ticks in northern climates.  Now, with shorter winters and warmer temperatures, their chance of survival increases. Longer summers increase the duration of the season when people may be exposed to ticks, thus leading to more people becoming infected. Further, climate change increases the range of reservoir and tick hosts such as deer and mice, again enhancing tick proliferation.

Q: Who is most affected by extreme weather?
Dr. Onello:
From a medical perspective, extreme weather impacts are often first observed in our youngest and oldest community members due to physiologic aspects of both youth and maturity. Children and the elderly are often most vulnerable to extreme weather events such as persistent heat waves or deep cold events, like a “polar vortex.”

In addition to the direct health effects of temperature extremes, there are indirect negative health consequences that result from unplanned power outages and loss of electricity from extreme weather events. One example would be the inability to continue home nebulizer breathing treatments for a teenager with asthma, should the electricity go out.
At the community level, it can be under-resourced communities and neighborhoods that suffer from severe weather events first and most acutely. These communities may not have the resources to respond quickly to counteract the negative effects of extreme weather happenings. However, as the recent 2023 “atmospheric river” rain events and floods in California have demonstrated, extreme weather events eventually impact everyone.

Q: What are you doing to further our understanding of how climate change impacts our health?
Dr. Onello:
Many of our state’s physicians, health professionals and health professional students are very concerned about the severity and complexity of the health impacts that we are already experiencing here in Minnesota. The nonprofit group Health Professionals for a Healthy Climate (HPHC) started in Minnesota and has been very active in education and advocacy work. The work of HPHC, which includes many members from the University of Minnesota, has been critically important in representing the human health concerns to policy makers and planners.

I was involved in a recent Minnesota Department of Health (MDH) research study that surveyed Minnesota’s health professionals regarding patient encounters influenced by climate-related factors (e.g. worsening allergies, wildfire smoke-induced asthma exacerbations, emotional distress from crop/farm losses). We are working with MDH to understand how our state’s changing climate (hotter summers, warmer winters) is affecting our population.

Studies like this can assist governmental agencies and others in developing new and effective educational materials for physicians and other health professionals. Health professionals urgently need new skills to recognize and intervene with at-risk patients and families to initiate climate safety response plans. These interventions should anticipate and/or reduce the health risks to patients from climate change.

Dr. Onello is an associate professor in the Department of Family Medicine and Biobehavioral Health at the U of M Medical School, Duluth Campus. Her research interests include rural physician workforce shortages, vaccination attitudes and environmental health. She has previously practiced as a family physician at Bay Area Health Center in Silver Bay MN and at the Lake Superior Community Health Center in Duluth MN. Currently she serves as a community preceptor at the Duluth Family Medicine Residency program in Duluth MN. She is a member of Health Professionals for a Healthy Climate, Northern Chapter. 

Dr. Bianco is an assistant professor in the Department of Family Medicine and Biobehavioral Health at the U of M Medical School, Duluth Campus. He is a director of primary care at Essentia Health and a family physician in Ely.


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