Habitat destruction and biodiversity loss, driven by deforestation, global transportation, encroaching cities, among others, can burden humans with more infectious diseases, says University of Vermont-Michigan (UVM) biologist Joe Roman.
This is part of a global pattern, say Roman and Environment Protection Agency (EPA) scientist Montira Pongsiri, that links biodiversity loss with infectious diseases.
"Lots of new diseases are emerging and diseases were once local are now global," adds Roman, a wildlife expert. "Diseases like West Nile Virus have spread around the world very quickly."
This is not the first time humans have faced a raft of new diseases. About 10,000 years ago, humans invented farming.
This move from hunting to agriculture brought permanent settlements, domestication of animals, and changes in diet. It also brought new infectious diseases, in what scientists call an "epidemiologic transition".
Another of these transitions came with the Industrial Revolution. Infectious diseases decreased in many places while cancer, allergies and birth defects shot up.
Now, it seems, another epidemiologic transition is upon us. A host of new infectious diseases - like West Nile Virus - have appeared. And infectious diseases thought to be in decline - like malaria - have re-asserted themselves and spread.
"Ours is the first article to link the current epidemiological transition," says Pongsiri, an environmental health expert in EPA Office of the Science Advisor, "with biodiversity change, decline and extinction".
"People have been working on this in individual diseases but no one has put all the studies together to compare them," says Roman.
"We've reviewed all those studies and show that emergence or re-emergence of many diseases is related to loss of biodiversity," says Pongsiri, according to an UVM release.
Their study will appear in the December issue of Bioscience.