The introduction of rabbit haemorrhagic disease virus in 1995 marked an important milestone in Australia’s long battle with introduced rabbits. This review considers what is known about the virus as a biological control agent: from its molecular structure to its ability to survive in the environment and its capacity for infecting rabbits and causing acute disease.
The impact of the virus on wild rabbit populations is strongly influenced by climatic factors such as rainfall and temperature, no doubt because these influence rabbit breeding and general population dynamics as well as the behaviour and abundance of insects that transmit the virus. Analytical models comparing epidemiology in temperate and semi-arid parts of Australia confirm that there are large differences in the timing, intensity and impact of disease spread.
Epidemiological studies within Australia have been carefully reviewed and compared with similar studies from New Zealand and Europe. However, despite common patterns emerging, better predictive models are still needed to provide a regional overview and for planning Australia-wide strategies if, as new evidence suggests, rabbits are beginning to develop genetic resistance to infection with RHDV. In the short term it is important to establish whether the virus is also changing and maintaining its infectivity. If this is the case, RHD will remain a useful biological control agent well into the future although, like myxomatosis, may not maintain levels of rabbit control adequate to avoid all environmental and economic impacts.
The introduction of RHDV brought high environmental, economic and social benefits, justifying its release, but land mangers now need to be aware that additional rabbit control effort is required to keep rabbits at the low levels seen in the last few years. Generally this is best achieved by using well-established methods such as poisoning and warren ripping to capitalize of the presence of RHD. Prospects for initiating new, effective outbreaks of the disease are limited because the virus circulates naturally and is widespread.
|Author||Brian D Cooke|
|Publisher||Invasive Animals CRC|
|Department||Invasive Animals Cooperative Research Centre|
|Control method||Biological Control|
|Region||Australia - national|
|Documents||A Review of Rabbit Haemorrhagic Disease in Australia [710 kb PDF]|
|Links||PestSmart Toolkit for Rabbits: www.pestsmart.org.au/pestsmart/rabbits/|