Culling Vampires Won’t Stop Rabies

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June 2012, Volume 10, Number 6

Culling Vampires Won’t Stop Rabies

New scientific research from Peru suggests that culling vampire bats – killing them with poisons, explosives and other means – does not curb the spread of rabies and may, in fact, be counterproductive, BBC News reports. It had been assumed, the British broadcaster said, that reducing bat numbers would control the spread of the rabies virus.

Common Vampire Bat © Merlin D. Tuttle, BCI

Vampire bats are found only in Latin America. While most mammals, including most bats, can contract rabies, the BBC said common vampire bats (Desmodus rotundus), which feed on the blood of mammals, especially livestock, are blamed for most infections. The findings of the international research team were published in theProceedings of the Royal Society B in the United Kingdom.

“We found that rabies is there no matter what,” co-author Daniel Streicker of the University of Georgia in the United States told BBC reporter Mark Kinver. “The size of the bat colony didn't predict the proportion of bats that were exposed to the virus.

“That’s important because if there is no relationship between bat population density and rabies, then reducing the bat population won't reduce rabies transmission within bats.”

Kinver reports that for the past three decades, Peru has focused primarily on culling vampire bats to stop or slow the spread of rabies in the South American nation.

The researchers analyzed data collected over 40 months at 20 sampling sites in Peru and concluded that culling was not having the desired effect. Streicker told the BBC that the results suggested that culling had a potentially counterproductive impact.

“In areas that were sporadically culled during the course of the study, we saw an increase in the proportion of bats exposed to rabies,” he said. Colonies that were frequently culled had slightly lower rates, the study showed, yet the ones that had never been culled had the lowest rates of all.

The BBC said it is possible that increasing levels of human encroachment exacerbated the problem.

Streicker said the team would continue the study for another two years, with the goal of developing a science-based solution. The researchers include scientists from the U.S. Centers for Disease Control and the University of Michigan in the U.S., and the Peruvian Ministries of Health and Agriculture and the National University of San Marcos in Peru.

They hope ultimately to help provide a more effective method to protect public health and agricultural interests from rabies, the BBC said.