Climate Change and Disease
In the past 20 years, global warming has been the culprit behind a growing incidence of different diseases. Researchers have suggested that 58% of diseases have been exacerbated by climate change, and that ignoring the connection between climate change and disease would be dangerous.
Insect vectors: Warming weather is increasing the range within which a disease can be transmitted by insect vectors. Mosquitoes, ticks, and fleas now thrive in places they’d never been found, and mild winters, early springs, and warmer temperatures are giving them more time to reproduce, spread diseases, and expand their habitats. Between 2004 and 2018, the number of reported illnesses from mosquito, tick, and flea bites more than doubled. As tropical species of insects move northward, they are bringing dangerous new pathogens with them.
Zoonotic exposure: More and more people are migrating into new areas, and disruptions to habitats can drive wildlife like bats, rodents, and primates to find new areas to live in, bringing them and the pathogens they carry much closer to human habitations, and making zoonotic exposures more likely. Wildlife carrying the rabies virus are expanding to new geographic areas of the United States (US). Arctic temperatures are rising more than twice as rapidly as the rest of the world, and warming temperatures in Alaska have led to increases in vole populations, which can spread diseases like Alaska pox to humans. And, as global temperatures rise, deadly diseases that are a threat in other countries, like Ebola, Lassa, Rift Valley fever, and monkeypox, will increase, along with the risk of them being imported into the US.
Environment: Floods and storms can lead to wastewater overflow, compromising safe drinking water and bringing pathogens, leading to a rise in noroviruses, rotavirus, and cholera. Rising temperatures have allowed certain disease-causing fungi to spread into new areas that previously were too cold for them to survive. In addition, melting ice and thawing permafrost in the Arctic can lead to the release of strains of ancient deadly pathogens, such as anthrax.
The World Economic Forum has stated that “Climate change is brewing as a bona fide public health emergency, “and an Intergovernmental Panel on Climate Change assessment is that the best-case scenario involving a 1.5°C rise over the next 20 years, will exacerbate the spread of infectious diseases. If sufficient action isn’t taken, the IPCC warned that an increase to 2°C could accelerate the rise of infectious diseases even more.