New tick-borne disease
In early 2020, a veterinarian in the Kimberley region of Western Australia noticed several dogs were presenting with severe symptoms of disease.
Samples from several affected dogs were sent to state government veterinarians. It wasn't anything they'd seen in Australia, but they had a good idea of what it was.
Staff at the state veterinary laboratories contacted scientists at our Australian Centre for Disease Preparedness (ACDP) and asked if they could run a test for canine ehrlichiosis.
This is one of the important jobs carried out by our staff at ACDP. They work with state and national agencies to diagnose emergency animal disease and provide advice and assistance to manage a response.
Diagnosis of disease
On May 30, 2020, staff at ACDP confirmed the dogs were infected with Ehrlichia canis (E. canis), a bacterium carried by ticks that causes the nationally notifiable disease, canine ehrlichiosis.
While the disease is found in most parts of the world, it had never previously been detected in Australia – except in dogs during quarantine, that had been imported from overseas.
The brown dog tick is the main carrier of this bacteria in other countries and this tick is present across large areas of mainland Australia.
Now that this disease has been detected in Australia, it is important that state government laboratories can test dogs for the disease.
New tests developed
In the first stage of the response, our staff developed a new technique for testing ticks and provided advice about tick sampling in the field.
The new test led to the detection of E. canis in ticks in northern SA, before any dogs have presented with the disease in the state.
Our staff also assisted the state labs in setting up the diagnostic tests to detect E. canis in dogs. This means they’re able to rapidly detect new cases and monitor its spread.
Managing the disease
Our scientists at ACDP are part of the response to managing this disease. They continue to provide confirmatory diagnostic testing as part of the ongoing surveillance program.
As Ehrlichiosis is a new disease to Australia, authorities would like to understand how it arrived here.
Using genome sequencing technology at ACDP, we have identified several near complete E. canis genomes. We can compare these to genome sequences from multiple locations, including overseas.
If we find a genome match, we may be able to narrow down where the bacterium originally came from. We may also be able to use genome sequence analysis to assist in determining how it may have spread between locations within Australia. Understanding the disease’s movement and evaluating possible entry routes could potentially help stop other diseases from entering the same way.
You can get more information about this disease on the Australian Government Outbreak page: Ehrlichiosis in dogs.