Throughout Latin America, common vampire bats transmit infectious diseases like rabies to animals and humans. Factors influencing the spread of disease within bat populations and transmission to other species are not well understood, making it difficult to predict rabies outbreaks in humans and livestock.
Now, a team of researchers led by associate professor Sonia Altizer of UGA, hopes to close these knowledge gaps with a $580,000 grant from the National Science Foundation for a three-year study of rabies in vampire bats in Peru.
Altizer and Ph.D. student Daniel G. Streicker, in collaboration with investigators at the U.S. Centers for Disease Control and Prevention, the University of Michigan, the National University of San Marcos and the Peruvian Ministries of Health and Agriculture, will explore how human activities affect rabies virus transmission in vampire bats and how those changes might alter the risk of rabies infection for humans and wildlife.
Streicker, who co-authored a recent paper on cross-species transmission of rabies that was published in the journal Science, said Peru is currently experiencing environmental changes, with deforestation and the introduction of livestock occurring in many areas.
“Most wildlife doesn’t benefit from this kind of change,” he said, “but vampire bats do.”
Vampire bats are responsible for a disproportionate share of human and livestock rabies cases because the bites that occur when they feed provide an ideal transmission mechanism.
“Introducing a herd of cattle is like putting out a huge platter of food for the bats,” said Altizer.”We’re looking at how this affects the population size of bats, and how it affects the transmission of rabies. We predict that more bats will make it easier for rabies to persist in an area year round.”
With a better understanding of how changes in bat densities and the effect that has on rabies transmission, researchers hope to help develop more effective rabies control strategies. Current efforts consist of killing bats, either by destroying caves where they roost or by poison. No one knows if killing bats actually helps reduce rabies transmission, Altizer said.
“It might be counterproductive,” she said. “If you kill the bats that are exposed to the virus and therefore immune, you’re taking away the protected population and clearing the path for an influx of susceptible animals, and that could potentially cause a rabies outbreak.”
The study also goes beyond implications for controlling the spread of rabies.
“The case of vampire bat rabies in Peru provides a microcosm to understand unintended feedbacks of human subsidization of wildlife through infectious diseases,” Streicker said.