"A team of biologists has just announced the first documented case of bird-to-bird malaria transmission in Alaska. Writing in the journal PLOS ONE, they've shown that this frequently fatal avian illness, which is normally associated with the tropics and temperate areas, may be expanding its range. Fortunately, avian malaria doesn't affect humans, co-author Ravinder Sehgal of San Francisco State University said, but the findings are particularly significant from a bird conservation as well as a climate change standpoint."
"'It also has implications for the spread of vector-borne human diseases as the climate changes,' Sehgal said.
Those implications are straightforward enough: insects that transmit diseases from one human to another are often limited in their geographic ranges, and the limits usually have to do with how cold it gets. As the climate warms up, the insects can expand into new ranges -- generally northward in the Northern Hemisphere, and also to higher altitudes -- bringing their viral or bacterial passengers along for the ride."
Michael D. Lemonick reports for Climate Central September 20, 2012.