One way to prevent future pandemics is to stop destroying natural habitats for wildlife, according to new research.
A team of scientists led by Cornell University researchers studied fruit bat behavior to better understand the risk of pathogen “spillover,” or when a disease-causing organism is transmitted from one species to another.
This research is particularly relevant for humans since every viral pandemic since the 1990s has been caused by “spillover” from animals to humans.
The findings of the study were published in the scientific journal Nature on Wednesday.
“Right now, the world is focused on how we can stop the next pandemic,” said lead author of the study Raina Plowright, professor in the Department of Public and Ecosystem Health at Cornell University.
“Unfortunately, preserving or restoring nature is rarely part of the discussion. We’re hoping that this paper will bring prevention and nature-based solutions to the forefront of the conversation.”
Researchers specifically studied fruit bats in Australia and their response to changes in their food supply and how that impacted the spread of the Hendra virus, which causes a deadly infection in both horses and humans.
A large part of that research involved creating datasets spanning from 1996 to 2020 that described fruit bat populations, the landscape of where they foraged, climate events, reproductive rates, years of food shortage, habitat loss and other facts.
Researchers also created computer models to analyze the data and as a result found two main drivers of “spillover:” habitat loss forcing bats to live in more agricultural areas where they are closer to humans and climate-induced food shortages.
Based on their analysis, researchers came to the conclusion that to stop the spread of Hendra, humans need to stop cutting down the forests where fruit bats live.
Scientists found that in the years when the bats’ food was abundant in its natural habitat during the winter months, the animals moved out of agricultural areas, and away from human communities, to feed in native forests.
When food was scarce, large fruit bat populations would split into smaller groups and migrate to agricultural or urban areas to find shelter and food in fig, mango and shade trees.
In the case of the Hendra virus, the pathogen spreads when bats urinate or drop feces on the ground where horses graze. Once a horse becomes infected, it could pass the illness to humans.
What was particularly amazing about the study, according to Emily Gurley, a professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health who was not involved in the study, was the model’s ability to predict spillover clusters based on numerous factors.
Epidemiologists have struggled to understand just how spillover happens, according to Gurley. This model makes it easier for humans to figure out what needs to be done in order to keep animals from spreading illnesses to humans.
“What they set out is a really beautiful example of a paradigm that could be followed to study spillovers and try to identify what we can do to stop them,” she said.