A report maps where in the US certain climate change-related health risks are prevalent
"Americans consider climate change as an 'over there' problem," one expert says
As President Donald Trump looks to curb the government’s enforcement of climate regulations, experts are concerned about how the action might impact public health.
“The current federal political climate in the United States bodes ill for the future of the world’s climate and by extension for the health of people around the world, Americans included,” said Dr. Mona Sarfaty, director of the program on climate and health at George Mason University’s Center for Climate Change Communication.
Sarfaty helped prepare a report, released last month by the Medical Society Consortium on Climate and Health, that mapped how climate change threatens the health of people across the United States and how those threats vary by region.
Extreme temperatures and weather events, poor outdoor air quality, contaminated food and water, mosquito- and tick-borne infections, wildfires and stresses on mental health are the climate-related health risks identified in the report by practicing physicians.
“There’s a gap between the public’s understanding of the health implications of climate change and physicians’ understanding of the health implications of climate change,” Sarfaty said. “Most people are not aware that climate change is a danger to their health, and physicians see that risk.”
Globally, about 12.6 million people die each year due to environmental risk factors such as pollution, extreme weather or climate-related disease, according to the World Health Organization.
Between 2030 and 2050, climate change is expected to cause 250,000 additional deaths per year around the world, according to the WHO – including in the United States.
‘An increase in disease anywhere … can affect us all’
“I think Americans consider climate change as an ‘over there’ problem or confined to poor countries,” said Dr. Jonathan Patz, a professor and director of the Global Health Institute at the University of Wisconson-Madison, who was not involved in the consortium’s report.
“Climate change is already influencing the frequency of heatwaves, flooding events and famines, as well as epidemics of vector- and waterborne diseases,” he said. “But in a globalized world, an increase in disease anywhere in the world can affect us all.”
People along the East Coast might be at a greater risk of mosquito- and tick-borne infections as the climate becomes hotter and more humid, creating an ideal breeding environment for those disease-carrying insects, according to the report.
Mosquitoes can transmit “dengue fever, Zika and West Nile virus, which has spread across the country and is popping up in outbreaks periodically, recently in Texas and Louisiana,” Sarfaty said.
Although a number of factors played a role in the recent Zika virus outbreak, climate-related changes in the environment might have influenced the spread of mosquitoes carrying the virus, according to a document from the Centers for Disease Control and Prevention (PDF).
“When increased rainfall leads to flooding, there can be a mixing of stormwater and sewage that leads to bacterial contamination in the water. This has been a problem in recreational lakes in the Midwest,” Sarfaty said. Bacterial contamination also can impact crops, leading to an increase in food-related infections.
“Warmer ocean water also makes a difference. Along the coast, there are cases of bacterial contamination in shellfish in the warmer months that have those waters more likely to cause infection when people swim there, especially if they have open cuts in their skin,” she said. “There have been some cases off the coast of Florida where people have gotten skin infections.”
Sarfaty added that areas along the Mississippi and Ohio rivers, such as in Missouri and Ohio, have experienced increased flooding in recent years, which also has led to a risk of contaminated water and water-related infections.
“There was an outbreak of cryptosporidiosis in Wisconsin some years ago that was related to one of these rain events,” she said.
Both the East and West coasts of the United States are threatened by extreme summer heat, flooding, storms, drought, poor air quality that can impact breathing, allergies and the mental health problems that come with dealing with those health threats, according to the consortium’s report.
“When people are displaced from their homes because of floods or extreme storms … this loss of home and separation from family and community leads to mental health impacts that can be reflected in substance abuse, alcoholism, domestic strife or violence, depression or anxiety,” Sarfaty said.
Meanwhile, the Great Plains and Midwest face a slightly different mix of climate change-related health impacts.
Is climate change making our food less nutritious?
Poor air quality, extreme weather and wildfires threaten the Great Plains, while food- and water-related infections and mosquito- and tick-borne diseases threaten the Midwest, according to the consortium’s report.
“You’ve got Lyme disease spreading west into the Midwestern states, Michigan, Missouri, Ohio, certainly spreading further north into Canada and also south into Virginia. … The tick that carries Lyme disease is now found in many more counties than it was before,” Sarfaty said.
Changes in climate also have affected some crops and food sources in the Great Plains and Midwest, according to the consortium’s report.
“One of the more recent findings that has been surprising to me is the increasing evidence that a carbon dioxide-enriched atmosphere is actually leading to crops that have lower nutritional value,” Sarfaty said.
“So it’s impacting the nutritional value of grains. That’s something which has been increasingly documented, and of course it’s very worrisome because the population depends on the growth of grains as a staple in our diet,” she said.
The most widespread climate-related health problem
Most climate scientists agree that humans are causing the planet to warm by polluting the atmosphere with heat-trapping greenhouse gases. Carbon dioxide is the primary greenhouse gas emitted through human activities, such as burning fossil fuels like coal, natural gas and oil at power plants.