Australian horse owners are facing a ‘mystery’ neurological virus affecting animals from Western Australia to Queensland.
From the outset suspected to be a mosquito-borne arbovirus, laboratory testing has revealed the cause as a combination of three diseases: Kunjin virus, Murray Valley encephalitis and Ross River virus, with the first of these responsible for most cases.
An estimated 246 cases have been reported this year, of which 22 horses have died.
Roger Lavelle, President of the Australian Horse Industry Council, was satisfied with the way Australia’s animal health system responded to the issue.
Mr Lavelle praised the early information sharing because it “kept everybody abreast of what’s happening, especially since a lot of people from industry, including myself, are not up to speed with the latest developments. It was really helpful in explaining how difficult it was to identify what’s caused the problem in some of these horses,” he said.
Even though mosquito numbers have decreased in some areas due to cooler weather, and the number of reported cases has plummeted, horse owners are urged not to become complacent.
Owners should try to prevent their animals from being bitten by insects through simple biosecurity practices including rugging, fly masks and using registered insect repellents. Ensuring that horses are kept in good condition will help build a strong immune system and minimise the risk of infection with arboviruses.
CSIRO scientists have shown that a new experimental vaccine helps to protect horses against the deadly Hendra virus. Dr Deborah Middleton, from CSIRO’s Australian Animal Health Laboratory, announced the successful progress to develop the vaccine, saying that trials so far have shown that it prevents the infection of horses with Hendra virus.
“A horse vaccine is crucial to breaking the cycle of Hendra virus transmission from flying foxes to horses and then to people, as it prevents both the horse developing the disease and passing it on,” Dr Middleton said.
Since it first appeared in 1994, the deadly Hendra virus has been confirmed in 40 horses and seven humans. Five of the 14 known outbreaks have spread to people; all horses either died or were destroyed and four of the people died.
Hendra virus is carried and transmitted by flying foxes, especially in the northern half of Australia. As there is currently no specific treatment for Hendra, it is extremely important to implement the following simple preventive measures in risk-prone areas:
For comprehensive information on the Hendra virus, visit the Queensland Department of Primary Industries and Fisheries’ web page.