After 2014 ranked as the warmest year in recorded history and observed the lowest maximum ice extent in the satellite record, climate change has yet again become a hot topic for top scientists and leaders around the world. The 2015 United Nations Conference on Climate Change (or COP21) in Paris came to a close on December 11, but talks of further climate change policies are just beginning for many nations.

Over two decades have passed since the last international agreement was reached at this annual conference. In 1992, the Kyoto Protocol – named after the summit’s location – became the first international treaty on climate change. This agreement set legal limits on greenhouse gas emissions and acknowledged that “global warming exists.” Now, the Paris agreement has marked a major victory between nations, though its terms only set a baseline for global warming policy.

Perhaps one of the most severe – least addressed – complications is that of disease prevalence as average global temperatures continue to increase. Vector-borne diseases such as malaria and dengue fever are most commonly a problem in tropical environments in South America, Africa and Southeast Asia. But with a global changes in heat, humidity and precipitation, tropical and subtropical insects may be able to survive in new areas.

Scientific American identified twelve diseases likely to become greater risks as a result of climate change. These diseases included bird flu, babesiosis, cholera, ebola, parasites, lyme disease, plague, red tides, rift valley fever, sleeping sickness, tuberculosis and yellow fever. In 2014, a record 68 million Americans travelled abroad, which is ten percent increase from the previous year. The article stated that this increased travel, ¨coupled with increased international travel to and from all 50 states, means that the U.S. is increasingly at risk for becoming home to these new diseases.¨ According to the NRDC, mosquitoes capable of carrying and transmitting disease like Dengue Fever, for example, now live in at least 28 states; Lyme disease infects tens of thousands of Americans every year and is projected to continue to expand throughout the U.S. and Canada; West Nile virus remains a problem in the United States since its introduction in 1999.
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An article in Time magazine examined the relationship between health care quality and infection rate. It found that ¨health care infrastructure and wealth — or lack it — have a lot more to do with the spread of infectious disease than climate change does, and that will continue to be the case even as the globe warms.¨ This concept is seen in the comparison of infection rates in Singapore and Burma. Both countries are found in relatively similar tropical environments, yet the wealthy country of Singapore has far less cases of malaria than Burma, a greatly impoverished country. Thus, though infection rates are likely to increase globally, impoverished areas are at higher risk of seeing immediate negative effects of climate change.

Richard Ostfeld of Cary Institute of Ecosystem Studies in Millbrook, New York stated that biodiversity loss is a “well-established consequence of climate change. In a number of infectious disease systems, such as Lyme disease and West Nile virus, biodiversity loss is tied to greater pathogen transmission and increased human risk.” So, even if our advanced health care systems in the U.S. can limit human infection, plants and animals will quickly become infected because they cannot adapt as well as humans. Scientific American noted that the risk of vector-borne diseases are increasing as a result of ¨human encroachment on remaining wild landscapes, mining and logging, and rapid global transport such as jet travel that promote the speedy spread of disease as does global trade in both livestock and wildlife.¨ This further supports Ostfeld´s concern that the biggest risk to human health may stem from the infection of natural food sources rather than direct infection.

Eleven states now have preparedness measures to address disease spread due to climate change. Illinois is not yet on this list.

Featured image courtesy of Huffington Post.