Humanosphere

The common refrain that climate change will bring malaria to U.S. shores again turns out to be cause for heated debate in scientific circles, according to Arthur Allen in the Washington Post:

The room where 10,000 Anopheles stephensi mosquitoes hatch each week is hot and humid and smells like the tropics – an appropriate surrogate for a warming world. The Johns Hopkins Malaria Research Institute in Baltimore, where the insects are raised, was created with a billionaire’s anonymous donation a decade ago, after a map printed in Scientific American suggested that by 2020 malaria could be breaking out in Baltimore, and across the eastern United States and Europe.

The idea that climate change will bring malaria and other tropical killers to our door turns out to be an extremely controversial one among ecologists, climatologists and biologists such as Marcelo Jacobs-Lorena, who runs the “insectary” at Johns Hopkins. “It’s a very complicated story,” says Jacobs-Lorena.

Allen reviews the evidence, and broad consensus, supporting the claim that climate change is expected to expand the range of the mosquitoes that carry malaria. But he quotes some experts who cite other factors causing the spread of disease, such as increased urbanization and poor insect control.

None of this is to say climate change never plays a role in disease. To emphasize the difficulty in establishing cause and effect in disease outbreaks, Allen notes that some high-profile scientists contend Haiti’s cholera outbreak is likely environmental in origin rather than due to human-to-human transmission. I’ve written about this hypothesis a few times on Humanosphere.

The gist of Allen’s article is that whatever climate change may be doing to patterns of disease spread, we don’t have to be helpless victims:

“Whether or not human engineering got us into this mess,” Allen writes, “perhaps it can get us out.”