Victoria fears it will be next to record cases of the deadly dog disease ehrlichiosis.
The state is warning dog owners to "avoid" bringing dogs into Victoria has a result of a confirmed case last week in South Australia.
Ehrlichiosis has been found right across Australia since its still unexplained arrival was detected in northern Australia less than a year ago.
Spread by the common brown tick, thousands of dogs across the north are already believed to have died from it.
One in 10 dogs in Australia which have contracted it, have died.
While there was some moves early by biosecurity officials to establish COVID-style border roadblocks to stop dog movement, it is clearly too late.
Only Victoria and the ACT are yet to record any cases on the mainland.
Because the tick is found right across the mainland, its spread has been rapid.
Last week South Australia recorded its first confirmed case in a dog in the far north of the state.
More infected ticks were found as well.
Victorian dog owners and veterinarians were this week warned to be on the alert.
"Reduce the risk of bringing the disease into Victoria by adopting or purchasing dogs within the state and avoid bringing dogs into Victoria," chief veterinary officer Dr Graeme Cooke said.
Symptoms of the disease includes fever, lethargy, loss of appetite, weight loss, cloudy eyes or conjunctivitis, pain, stiffness, nosebleeds, bruising on the gums or belly, and enlarged lymph nodes.
"With dogs travelling readily around Australia, we need to be particularly mindful of these symptoms if they have come from another state or territory with confirmed cases and brown dog ticks present," Dr Cooke said.
"Protect your dogs from ehrlichiosis by regularly checking them for ticks, using effective tick control and seeking veterinary advice promptly if they become unwell. Be particularly vigilant if you've been interstate with your dog."
Ehrlichiosis is potentially a deadly dog disease and there is no vaccine, but antibiotics may assist in managing the disease if affected dogs are treated early.
"This is a notifiable disease in Victoria, which means it must be reported to the Emergency Animal Disease Watch Hotline on 1800 675 888 when suspected," Dr Cooke said.
Dog owners should regularly check their animals for ticks by running your fingers through their coat, on the skin, paying attention to the head, neck, ears, chest, between their toes and around their mouth and gums.
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