The Current

Why experts say tackling deforestation could be key to stopping future pandemics

Experts studying how diseases make their way from animals to humans say we need to rethink the way we use and manage land if we want to prevent future pandemics.

Clearing land increases risk of diseases spillover from wildlife: Dr. Jonathan Epstein

A forest activist inspects a land clearing and drainage of peat natural forest in Riau province, Sumatra, Indonesia, in 2014. Large swaths of the country's forest areas are being cleared to make way for producing palm oil, says Terry Sunderland, a forestry professor at the University of British Columbia, and that can contribute to the spread of disease. (Ulet Ifansasti/Getty Images)

Story Transcript

Experts studying how diseases make their way from animals to humans say we need to rethink the way we use and manage land if we want to prevent future pandemics.

"This message is critical and it needs to be delivered now more than ever, because in the midst of this [COVID-19] crisis, we need to make sure that it doesn't happen again," veterinarian and disease ecologist Dr. Jonathan Epstein told The Current's Matt Galloway.

"And to really do that, we have to start thinking about how these things happen in the first place."

According to Epstein, processes like deforestation, or converting agricultural land into urban spaces, are responsible for about a third of all epidemics. When people start cutting roads through forests, for example, or create more opportunities to come in contact with wildlife, it makes it easier for viruses to jump from their wildlife hosts to people or domestic animals.

COVID-19, which is believed to have been transmitted from bats to humans by way of another animal, is one example of how this can happen. But there are other, more deadly diseases, such as the Nipah virus, that can do the same, Epstein said.

Dr. Jonathan Epstein, a veterinarian, disease ecologist and vice-president of EcoHealth Alliance, says deforestation is responsible for about a third of all epidemics. (Submitted by Jonathan Epstein)

"It is very much an odds game … in that there are some number of viruses that already have the genetic ability to jump from the animals that they normally occur in, into other animals or people," said Epstein, who is also a vice-president of EcoHealth Alliance, a non-profit working to protect wildlife and public health from the emergence of disease.

"The more chances we give that virus to do so, the more shots on goal, the more likely we're going to see a virus that is able to efficiently spread amongst people."

That's why governments need to work on preventative policies, rather than reacting to pandemics, Epstein said.

Link between deforestation and malaria

Kimberly Fornace, an epidemiologist at the London School of Hygiene & Tropical Medicine in the U.K., agrees.

She's been studying a form of malaria found in macaque monkeys on the island of Borneo, in Southeast Asia, which has now become the main cause of malaria among people in Malaysia.

She told Galloway that she and other researchers found deforestation was driving transmission of the disease.

Kimberly Fornace is an epidemiologist at the London School of Hygiene & Tropical Medicine in the U.K. (Submitted by Kimberly Fornace)

"Macaques were increasingly moving into farm areas, raiding crops and actually roosting or spending the night in very close proximity to where people were staying," she explained.

Given the links between deforestation and disease, Fornace said people should be exploring different methods of land management that keep wildlife habitats intact, and therefore reduce the risk of viruses jumping from animals to humans.

Diversifying food systems 

But it's also time to rethink the food we eat, and how we produce it, says Terry Sunderland, a professor of forestry at the University of British Columbia.

"Our whole food system is reliant on a very few commodities which require large amounts of land," he told Galloway, citing goods like palm oil, soy, chocolate and coffee. 

"And the transformation of land into agriculture is directly related to deforestation." 

A view of land clearing for a palm oil plantation in Riau province, Sumatra, Indonesia, on July 11, 2014. Sunderland says relying on small-scale farmers, who use smaller plots of land, can help lessen the impact of deforestation. (Ulet Ifansasti/Getty Images)

In places like Indonesia or Malaysia, for example, large swaths of forest are being cleared and transformed into "vast monocultures" of oil palms, Sunderland said. 

Meanwhile, lots of food is being squandered. According to the United Nations, about 17 per cent of food produced globally goes to waste.

Sunderland said it's possible we need to reflect on our diets, and whether we really need items that contribute to deforestation. 

Relying on smaller-scale farmers could also help lessen the impacts of deforestation, said Sunderland.

Sunderland is professor of forestry at the University of British Columbia. (Submitted by Terry Sunderland)

He said they produce more diverse foods with smaller plots of land, which are also more resilient to environmental shocks, including the spillover of viruses from animals to humans.

"As a society, we tend to be reactive," Sunderland said.

"We need to be proactive instead of reactive as a society and start looking at what we can do to avoid these situations in the future."

Written by Kirsten Fenn. Produced by Alison Masemann.

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