How Forest Loss Leads to Spread of Disease?

Wednesday, April 8, 2020 - 13:19

Researchers of Stanford University have shown that as people continue to transform natural habitats into agricultural land, viruses that jump from animals to people will likely become more common.

According to the analysis published in Landscape Ecology, researchers reveal how the loss of tropical forests in Uganda puts people at greater risk of physical interactions with wild primates and the viruses they carry, phys.org reports.

The findings have implications for the emergence and spread of infectious animal-to-human diseases in other parts of the world, and suggest potential solutions for curbing the trend.

"At a time when COVID-19 is causing an unprecedented level of economic, social and health devastation, it is essential that we think critically about how human behaviors increase our interactions with disease-infected animals," said study lead author Laura Bloomfield, an MD student in the School of Medicine and a Ph.D. candidate in the Emmett Interdisciplinary Program in Environment and Resources within Stanford's School of Earth, Energy & Environmental Sciences.

"The combination of major environmental change, like deforestation, and poverty can spark the fire of a global pandemic."

People have converted nearly half of the world's land into agriculture. Tropical forests have suffered the most, with some of the highest rates of agricultural conversion over the last few decades.

When people venture into forested areas for resources and when animals venture out of their habitats to raid crops, the chances increase for transmission of zoonotic—or animal-to-human—disease. A prime example is HIV, which is caused by a virus that jumped from wild primates to humans via infected bodily fluids.

"We humans go to these animals," study co-author Eric Lambin, the George and Setsuko Ishiyama Provostial Professor in Stanford's School of Earth, Energy & Environmental Sciences. "We are forcing the interaction through transformation of the land."

The researchers were surprised to find some of their assumptions turned upside down. For example, small fragments of residual forest—not larger expanses of habitat—were most likely to be the site of human-wild primate contacts due to their shared borders with agricultural landscapes.

Similarly, the researchers speculate that increasing intrusion of agriculture into forests and resulting human activities in these areas could lead to more spillover of infections from wild primates to humans worldwide.

"At the end of the day, land conservation and the reduction of forest fragmentation is our best bet to reduce human-wild animal interactions," said study coauthor Tyler McIntosh, a former graduate student in the Stanford Earth Systems Program now working at the Center for Western Priorities.

Opinions


Popular News

Latest News