Researchers across the globe are collaborating to learn what causes infectious diseases to transmit to humans in the hopes of developing ways to predict where and when the next pandemic may emerge.
According to a 2021 study, 60 to 70% of human infectious diseases originally came from wild animals. Some scientists believe this phenomenon — known as 'zoonotic spillover — may have caused the SARS-CoV-2 virus to jump from bats to humans, resulting in the COVID-19 pandemic.
Since the pandemic emerged, researchers have stepped up efforts to fully understand how viruses found in wild animals transmit to humans.
Some scientists believe that pressures from human encroachment on wildlife habitats may play a role in the frequency of zoonotic spillover. For example, a 2022 study published in the journal Nature suggests that habitat loss and climate change increase the spillover risk.
Now, a group of 70 scientists in seven countries aims to find out how and when bats transmit viruses to hopefully predict when and where the next potentially deadly virus might transmit to humans. The group, called BatOneHealth — founded by Raina Plowright, a disease ecologist and co-author of the Nature study and a recent paper published in Ecology Letters — hopes to gain more understanding of bat-to-human viral transmission through several key investigations.
These investigations include field studies of bats in global hotspots, understanding bat immune systems and behaviors, predicting which viruses infect humans, and modeling virus dynamics. They are also exploring ways to restore habitat to prevent zoonotic spillover.
The team’s research focuses on bat-borne viruses, including Hendra, Nipah, and coronaviruses.
Institutions in the United States involved in the research include Montana State University, Cary Institute, Cornell University, Johns Hopkins, Penn State, Rocky Mountain Lab, Texas Tech, UC Berkeley, UC Los Angeles, and Colorado State.
In Montana, BatOneHealth team member Agnieszka Rynda-Apple, an immunologist from Montana State University, plans to accelerate her laboratory’s work by starting a breeding colony of Jamaican fruit bats this winter. One of the team’s goals is to investigate the impact nutritional stress has on viral load — which is the amount of virus a bat has in its system.
"We’re collaborating on the question of why bats are such a fantastic vector," said Rynda-Apple in a news report. "We’re trying to understand what is it about their immune systems that makes them retain the virus, and what is the situation in which they shed the virus."
Although Rynda-Apple and her team are already involved in similar experiments, the bat breeding colony will help expand on those investigations.
In the news report, Andrew Hoegh, an assistant professor of statistics at MSU, explained that thoroughly understanding how environmental change impacts bat nutritional stress and contributes to zoonotic spillover may make it possible to identify ecological countermeasures to stop the spillover cycle.
Ultimately, the global BatOneHealth team hopes their research will help develop strategies to protect humans, animals, and ecosystems from emerging infectious diseases caused by zoonotic pathogens.
- Genetics and Microbiology. Zoonotic spillover: Understanding basic aspects for better prevention.
- Nature. Pathogen spillover driven by rapid changes in bat ecology.
- BatOneHealth.org. Science Solutions to Stop Spillover.
- Ecology Letters. Ecological conditions predict the intensity of Hendra virus excretion over space and time from bat reservoir hosts.
- Kaiser Health News. A Secret Weapon in Preventing the Next Pandemic: Fruit Bats.