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Pressure on forests from unhealthy diets may increase spread of viruses, scientist says

Food production destroying critical green buffer
, Thursday, 27 Aug 2020
Rice fields in Vietnam. CIFOR/Terry Sunderland

Theories surrounding the origins of the SARS-COV2 coronavirus often point to disturbances in the natural environment. Through disruptions and human encroachments, pathways are formed and unlikely connections between species made.

Research indicates that COVID-19 was almost certainly transmitted from a pangolin or a bat to humans in a wet market in the city of Wuhan, China.

While the evidence shows that the trade in wildlife can spread pathogens and infectious diseases, human eating habits may be a big part of the equation in more ways than one.

“The food most associated with biodiversity loss also tends to be connected to unhealthy diets across the globe,” argues a senior associate scientist with the Center for International Forestry Research (CIFOR) in a new article in The Conversation, referring to the production of such food staples as rice, wheat and maize.

Since the second half of the 20th century, agricultural intensification has been the dominant method of producing large amounts of food.  Goals have included increasing staple crop yields and large-scale beef production.

Yet, the transition to intensive, high-yielding food production reliant on a limited number of crop and livestock species has failed to adequately address global malnutrition, writes Terry Sunderland, who is also a professor in the Faculty of Forestry at Canada’s University of British Columbia.

“Nearly 800 million people still go to bed hungry, one in three is malnourished, and up to 2 billion people suffer some sort of micronutrient deficiency and associated health impacts, such as stunting or wasting,” he writes.

As well, agricultural intensification leads to deforestation and landscape degradation, permitting conditions for the further spread of a range of such virulent zoonotic diseases as SARS, MERS, H1N1, Chikungunya, Zika and Ebola, which has been linked to deforestation, Sunderland adds.

“The agricultural sector is responsible for up to 30 per cent of greenhouse gas emissions, soil erosion, excessive water use, the loss of important pollinators and chemical pollution, among other impacts,” he states.

“Roughly 70 percent of the global forest estate is now within a kilometer of a forest edge . . . destroying that critical buffer that forests provide.”

“Farming large numbers of genetically similar livestock along the forest frontier may provide a route for pathogens to mutate and become transmissible to humans. Forest loss and landscape change bring humans and wildlife into ever-increasing proximity, heightening the risk of an infectious disease spillover,” he adds.