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DCL
The connection between climate change and infectious diseases has been somewhat well documented in developing countries, where the risk factors are greater (more disease-carrying insects) and more numerous (less access to clean drinking water), but the connection is only beginning to be studied in more developed regions of the world. And it's cause for increasing concern.
As climate patterns change, the organisms that depend on them change with them. Warmer temperatures allow pathogens to develop faster, for example, or disease-carrying organisms to survive longer or proliferate more successfully. Changing climates can increase the geographic range of pathogens, inviting insects or other organisms where they would never have gone before, and in greater numbers—and increased flooding can create breeding habitats for many disease-carrying organisms.
Lyme disease, for example, could be expected to spread into Canada, where it is currently uncommon. But as temperatures warm, tick populations could spread north from their existing habitats in the U.S. and if they reach the expected 200 km by 2020, Alberta and Saskatchewan could be the next victims of Lyme disease.
Other diseases could spread as well: in North America, that could mean other tick-transmitted diseases, as well as those carried by mosquitoes, including Dengue. Europe and Australia would also suffer as ticks, sandflies, mosquitoes and other organisms expand geographically and with them, the incidences of diseases they carry.
Seasonal illnesses, such as the flu, could also be exacerbated with rising temperatures and changing seasons, and altered ecosystems could lead to an increase in fungal infections.
There's even talk of a potential re-establishment of autochthonous malaria in the U.S. and Canada, a locally-acquired strain of the disease that was once endemic. Time to add malaria to the list of reasons to fight climate change.
