A new study finds that the closer animals get to humans, the more diseases they spread.

Researchers in the US and Australia have made a timely investigation into why novel diseases spread from animals to humans.

Based on data from 139 viruses, they found that domesticated animals, primates and bats have passed on more viruses to humans than other species, but that wild animals also spread diseases when endangered by human activities.

Their results suggest that domestication of animals, destruction of habitats and hunting of wild animals are key drivers of disease transmission - a threat that the researchers say may be under-reported and underestimated.

“We found that spillover risk has been highest from threatened wild animals that have declined due to exploitation and loss of habitat,” the authors state.

“Animals that are increasingly common, including domestic species and wild mammals that have increased in abundance by adapting to human-dominated landscapes, have also shared more viruses with humans than more rare species.

“Our findings highlight human activities that not only increase zoonotic disease risk but also perpetuate declines in wildlife.”

The study is accessible here.