RABBIT owners are being warned to protect their pets from a deadly new strain of calicivirus which is spreading across the Perth Hills and foothills.
Department of Agriculture and Food research officer Susan Campbell said the haemorrhagic virus strain known as RHDV2 had been confirmed in the Shire of York, Perth Hills, Lesmurdie and Forrestfield.
Dr Campbell said RHDV2 was detected in a wild rabbit in Canberra in 2015 and the virus had since been found in New South Wales, Victoria, South Australia, the Northern Territory and Tasmania.
“Rabbits are a widespread and common pest,” she said.
“A Czech strain of RHDV1 has been used as a biocontrol for rabbits in Australia since 1996 and has had a significant impact in reducing pest populations.
“It is important to note that RHDV2 is different, and it is not known how it arrived in Australia.”
Mt Helena Vet Clinic veterinarian Dr Tanya Lovelock, who has a special interest in rabbit medicine, said there was no cure for the new, highly contagious virus.
“RHDV2 causes rapid death in rabbits and initially signs such as inappetance and fever may be noticed,” she said.
“The current calicivirus vaccine is not fully protective against RHDV2.”
Dr Lovelock said to help prevent infection it was recommended pet owners and breeders kept their rabbits indoors or in an enclosed environment.
“Rabbits can be infected through objects contaminated with the virus such as clothing and shoes, flies, fleas, birds and other animals such as rodents,” she said.
“Owners should ensure housing is kept clean to reduce the attraction of flies and netting should be placed around the hutch.
“Outside exposure should also be avoided in the early morning and late afternoon to reduce insect exposure.
“Owners should wash their hands thoroughly before handling their rabbit and we also recommend new rabbits are quarantined for five days before introducing them to your other rabbits.”
Dr Campbell said the NSW Department of Primary Industries was investigating options to develop a new vaccine that had improved effectiveness against both RHDV1 and RHDV2 variants.
“Whilst the new vaccine is being developed, a revised vaccination protocol using the existing vaccine has been suggested for rabbits,” she said.
“However it is not known to what extent this will confer protection.”
Dr Campbell said researchers were monitoring how rapidly RHDV2 was spreading and what impact it may have on pest rabbit populations.
“RHDV2 was first detected in the Perth metropolitan area in mid-August,” she said.
“The new strain is believed to have spread through the metropolitan area, northern agricultural region and Great Southern over the past four to six weeks.
“To date the Department of Agriculture and Food WA has confirmed 12 rabbit mortalities from RHDV2.”
Dr Campbell said even if an outbreak reduced pest rabbit populations, it was vital that follow-up conventional control methods were used.
Earlier this year the Australian Pesticides and Veterinary Medicines Authority approved the use of K5, a Korean strain of the calicivirus disease.
It follows a decade-long program by the Invasive Animals Co-operative Research Centre to investigate biological tools to curb escalating rabbit numbers. The new strain is scheduled for release in autumn 2017.
Residents and landholders are encouraged to report suspected outbreaks of RHDV2 to the department by contacting the Pest and Disease Information Service on 1800 084 881. Evidence of rabbit disease can also be reported online through the new RabbitScan App and website www.rabbitscan.org.au
BY SARAH BROOKES