How to Curtail the Risk of Future Pandemics

Altering how we use land can reduce the risk of future spillovers of infectious diseases.

Deforestation in the Amazon
Deforestation in the Amazon. luoman / Getty Images

There has been plenty of ink spilled about how life will look after the COVID-19 pandemic, from open-air schools to scattered desks in offices – but we don't hear much beyond that. Sure, we are still in the thick of it, but really there's no time like the present to start thinking about how to prevent the next outbreak of zoonotic disease. (Zoonotic diseases are those that "jump" from animals to humans, like the new coronavirus, as well as SARS, ebola, and MERS.)

Previously, Treehugger reported on the Wildlife Conservation Society's strategy to reduce the risk of future pandemics in three steps; stop wildlife trade, stop wildlife consumption, and stop destroying nature.

Now researchers from University College London (UCL) have dug deeper and conclude that:

We may need to alter how we use land across the world to reduce the risk of future spillovers of infectious diseases.

"Global changes in land use are disrupting the balance of wild animal communities in our environment, and species that carry diseases known to infect humans appear to be benefiting."

The research, which has been published in the journal Nature, may provide insight into future spillovers of diseases originating in animals.

The team, led by the UCL Centre for Biodiversity and Environment Research, looked at data from 6,801 ecological communities from six continents, and found that animals that carry human-disease-causing microorganisms were more common in landscapes intensively used by people, explains UCL. All told, they examined evidence that included around 7,000 species, 376 of which are known to carry human-shared pathogens.

As examples of land-use change, the authors cite the conversion of natural habitats to agricultural or urban ecosystems.

Lead author Rory Gibb says, "The way humans change landscapes across the world, from natural forest to farmland for example, has consistent impacts on many wild animal species, causing some to decline while some others persist or increase." He adds:

Our findings show that the animals that remain in more human-dominated environments are those that are more likely to carry infectious diseases that can make people sick.

The team suggests that similar influences may be behind whether a species can tolerate humans and how likely it is to carry potentially zoonotic diseases.

"Other studies have found that outbreaks of emerging zoonotic infectious diseases appear to be increasingly common," says co-lead author Doctor David Redding. "Our findings may help to explain that pattern, by clarifying the underlying ecological change processes that are interacting to drive infection risks."

According to research by Navin Ramankutty, an agricultural geographer at the University of British Columbia (and not involved in the UCL study), only 23% of Earth's land remains wild. Farmland and human settlement are taking over, pushing out native species and creating dangerous opportunities for pathogens to find their way into human populations.

The UCL study concludes that "global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease."

"Our findings provide a context for thinking about how to manage land use changes more sustainably in ways that take into account potential risks not only to biodiversity," says Redding, "but also to human health."