Let’s not get ‘batty’ over Hendra virus

First published 1 September 2011

Relocating or culling bat colonies could increase Hendra virus outbreaks, according to James Cook University academics.

Dr Lee Skerratt, who is Leader of the One Health Research Group within the Anton Breinl Centre for Public Health and Tropical Medicine in the School of Public Health, Tropical Medicine and Rehabilitation Sciences, said flying foxes were a ‘reservoir host’ for Hendra virus.

“We just don’t know, the science has not been done. We need to understand viral dynamics in flying foxes before we consider using these ideas as management options for Hendra virus,” Dr Skerratt said.

Outbreaks have occurred when the virus ‘has spilled over’ into horses, which appear particularly susceptible to the virus, and humans have become infected from horses, Dr Skerratt said.

“Outbreaks of Hendra virus continue and there has been a significant increase in outbreaks this year - 16 this year versus 14 in total from 1994-2010. Hence, there is a need to better manage the risk to horses.”

He said while there had been no human cases this year, which was promising in terms of risk management for humans, the relative large number of horse cases was cause for concern.

“There are various ways to improve the management of the risk of Hendra virus, including preventing horses being exposed to flying foxes and their excrements. People should take hygiene precautions when handling horses as infected horses can transmit the virus before they become obviously ill.”

Dr Jon Luly, from the School of Earth and Environmental Sciences, said culling flying foxes was an impractical, cruel and potentially ineffective approach to reducing the incidence of Hendra virus.

It would also deprive society and the environment of ecosystem services flying foxes perform better than any other animal, he said.

“Colony re-location is unlikely to reduce the risk of Hendra virus transmission to horses and may even make the problem worse. Flying fox colonies do not pose a direct risk to public health. The expense of colony relocation or dispersal far outweighs any apparent benefits from a biosecurity point of view.”