Climate change is already having clear effects on human health, according to a new review that describes the situation as a "health emergency."
"Climate change is causing injuries, illness and death now due to heat waves, infectious diseases, food and water insecurity and changes in air quality, among other adverse effects," said Kristie Ebi, one of the report's authors.
She heads the University of Washington's Center for Health and the Global Environment in Seattle.
According to Ebi, "the science is clear" that, for every unit increase in global warming, there is an increase in these broad health risks. That is, she said, if no action is taken to reduce greenhouse gas emissions.
Carbon dioxide – which remains in the atmosphere for centuries – is the main issue that fuels global warming. In the United States, the main source is the burning of fossil fuels for electricity, heat and transportation, according to the US Environmental Protection Agency (EPA).
Today, the average global temperature is 1 degree Celsius higher than it was in pre-industrial times, according to the review. Most of this increase has occurred since the 1970s.
Some of the health effects associated with climate change are intuitive: more frequent and more intense heat waves increase the risk of heat-related diseases, for example.
Other health effects, however, are less obvious.
Air pollution related to greenhouse gas emissions may exacerbate certain chronic diseases, including heart disease and lung conditions, the review shows. Climate change can also fuel the spread of insect-borne infections, such as Lyme disease and West Nile, and even contribute to food poisoning – contributing to heavy rains, rising sea levels and floods that can contaminate food supplies. foods.
"Climate events" such as floods and forest fires are a direct threat – causing injuries and deaths, Ebi and his colleague Dr. Andy Haines noted. But they can also charge the price in other ways.
After a huge forest fire in 2008 in North Carolina, for example, the researchers tracked the health impact. They found that in counties affected by fires, travel to the emergency department for heart disease and respiratory conditions increased.
The review was published on January 17 in New England Journal of Medicine.
Here and now
Many people may not be aware of the breadth of health effects associated with climate disruption, said Dr. Regina LaRocque, who co-wrote a review commentary with the review.
And she emphasized that it is not a theoretical issue that people may face in the future.
"This is happening here and now," said LaRocque, an infectious disease specialist at Massachusetts General Hospital in Boston.
"This is important for people to notice," she added. "I think humans are not really designed to respond to a threat until they are in immediate danger."
On how to respond, LaRocque said that health systems have a responsibility to serve as a "model". In the United States, she noted, the health sector accounts for 10% of all greenhouse gas emissions – because of its size and the energy required to run hospitals and other facilities 24 hours a day.
According to LaRocque, some health systems have started to do something about it – switching to more environmentally friendly energy sources such as solar or wind power. And that needs to continue, she said.
The public can also do their part, Ebi pointed out. She gave examples such as choosing to walk or ride a bicycle instead of driving; eat less meat and more plant foods, and put computers to sleep when they are not being used.
These actions are also healthy and save money for individuals, Ebi noted.
And when it comes to sweeping political changes, she said, people can make a difference with their vote. "If climate change is important to you, then vote for the politicians who are committed to action," Ebi said.
"Mitigation" policies to combat climate change cost money. But, said Ebi, this would be fought by the economy to avoid hospitalizations and premature deaths.