A study warns that more people around the world might contract Zika, dengue, chikungunya, and other mosquito-borne diseases in the next 30 years.
According to researchers, climate change is placing more than half a billion people at risk. The problem will not be isolated to the tropics either; areas like Canada and Northern Europe where mosquito-borne diseases are currently unknown will be a hotbed for yellow fever and tiger mosquitos.
Climate Change-Driven Mosquito Disease Transmission
The team created mathematical models of climate change and used predictions of future climate change under different emission scenarios to create a map where and when populations would be at risk of mosquito-borne diseases.
Right now, the researchers said that about 6 billion people around the world are at risk of mosquito-borne diseases for a month or more each year. However, by 2050, more than half a billion more would be at risk of transmission.
They explained that climate change is pushing cooler weather further into the pole, making areas such as Canada and Northern Europe hospitable to mosquitos and their pathogens.
"These diseases, which we think of as strictly tropical, have been showing up already in areas with suitable climates, such as Florida, because humans are very good at moving both bugs and their pathogens around the globe," explained Sadie Ryan of the University of Florida, the lead author of the study.
The study also found that climate change might also see a decline of certain mosquito-borne diseases, especially in countries nearer to the equator. While yellow fever and tiger mosquitos move upward and spread across Europe, the risk of disease might decrease in west Africa and southeast Asia where the mosquitos will find the climate in tropical countries too hot.
Planning Should Begin Now
The researchers explained that the goal of the study is to encourage governments and public health officials to begin preparing before the mosquitos arrive in areas unaccustomed to the pathogens. They hope that the study would lead to the creation of a global health plan suited for the changing climate.
"Newly exposed populations tend to see erupting epidemics," added Ryan, "and for the diseases we have seen recently, like Zika, first exposures tend to have worse outcomes, in terms of symptoms, and public health response, so we should be on the lookout for those new areas, under any future scenario."
The study was published in the journal PLOS Neglected Tropical Diseases on March 28, Thursday.