WASHINGTON, Sept. 19 (Xinhua) -- Malaria has been found in birds in parts of Alaska, and global climate change will drive it even farther north, according to a new study published on Wednesday in the journal PLOS ONE.
The spread could prove devastating to arctic bird species that have never encountered the disease and thus have no resistance to it, said San Francisco State University Associate Professor Ravinder Sehgal, one of the study's co-authors. It may also help scientists understand the effects of climate change on the spread of human malaria, which is caused by a similar parasite.
Researchers examined blood samples from birds collected at four sites of varying latitude in Alaska, with Anchorage -- the largest city in the U.S. state -- as a southern point, Denali and Fairbanks as middle points and Coldfoot as a northern point, roughly 600 miles north of Anchorage. They found infected birds in Anchorage and Fairbanks, but not in Coldfoot.
Using satellite imagery and other data, researchers were able to predict how environments will change due to global warming -- and where malaria parasites will be able to survive in the future. They found that by 2080, the disease would have spread north to Coldfoot and beyond.
"Right now, there's no avian malaria above latitude 64 degrees, but in the future, with global warming, that will certainly change, " Sehgal said. The northward spread is alarming, he said, as there are species in the North American arctic that have never been exposed to the disease and may be highly susceptible to it.
Researchers are still unsure how the disease is spreading in Alaska, and are currently collecting additional data to determine which mosquito species are transmitting the Plasmodium parasites that cause malaria.