A global study mapping human diseases that come from animals like tuberculosis, AIDS, bird flu or Rift Valley fever has found that just 13 such diseases are responsible for 2.4 billion cases of human illness and 2.2 million deaths a year.
The vast majority of infections and deaths from so-called zoonotic diseases are in poor or middle-income countries, but "hotspots" are also cropping up in the United States and Europe where diseases are newly infecting humans, becoming particularly virulent, or are developing drug resistance.
And exploding global demand for livestock products means the problem is likely to get worse, researchers said.
"From cyst-causing tapeworms to avian flu, zoonoses present a major threat to human and animal health," said Delia Grace, a veterinary epidemiologist and food safety expert with the International Livestock Research Institute (ILRI) in Kenya and lead author of the study.
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