EXOTIC TICK-BORNE DISEASE EHRLICHIOSIS DETECTED IN WA’s KIMBERLEY REGION IS A FIRST IN AUSTRALIAN DOGS

An exotic tick-borne disease, never seen before in Australian canines, has been found in a small number of sick dogs tested in Western Australia’s far north Kimberley.

Ehrlichiosis is a bacterial illness transmitted by ticks, particularly common in tropical and sub-tropical regions but this is the first time it has been confirmed in dogs which haven’t been imported from another country.

The affected dogs, in Halls Creek and Kununurra, have been treated by a private veterinarian in the region.

The bacteria, Ehrlichia canis, which causes the disease in dogs, was later confirmed through laboratory testing by the Australian Centre for Disease Preparedness.

Department of Primary Industries Chief veterinary officer Michelle Rodan said authorities were unsure how or when ehrlichiosis first arrived in the Kimberley.

“We haven’t detected what the original source is … any dog that entered Australia which is infected and has been bitten by a tick could be a source of the outbreak.

“Once it’s in the tick population, it’s very difficult to control. So the first stage is defining how widespread the distribution is and then in the interim trying to contain it to a region.”

The flu-like signs of infection for dogs can include; fever, lethargy, enlarged lymph nodes, loss of appetite, weight loss and bleeding disorders, which can resemble other tick-borne diseases already present in northern WA, such as anaplasmosis.

If left untreated, ehrlichiosis can be fatal to the dog.

Surveillance and control measures in place

The National Consultative Committee of Emergency Animal Diseases has met to discuss response measures.

Dr Rodan said while surveillance was being carried out to determine the distribution of the disease, DPIRD had introduced measures to control the movement of dogs out of the Kimberley.

“We’ve already been in contact with private vets to get some samples from dogs going through their clinics, to get a sense of how broadly spread it is — not only in the Kimberley but across the north of Australia.”

“Any dogs moving out of the Kimberley region must be clinically healthy and have had a tick treatment applied [and] DPIRD will require notification prior to movement of dogs outside of the region.”

Dr Rodan said the high numbers of stray and wild dogs in the region could pose a challenge to controlling the spread of the disease.

“There has been some surveillance last year and in previous years that would lead us to think it’s not being detected in the wild dog population; [but] wild dogs may become a source of infection if it continues to spread,” she said.

“To help prevent infection, owners should maintain dogs on a tick control program.

Ehrlichiosis is a nationally notifiable disease, under the Exotic Diseases of Animals Act 1993.

The disease cannot be directly passed from infected dogs to other dogs or humans.

However, while infected dogs do not transmit ehrlichiosis to people, in rare cases, infected ticks may transmit the bacterial illness to people.

Key points:

• Ehrlichiosis is a bacterial illness transmitted by ticks — it’s been found in Australian dogs for the first time in the Kimberley.
• Signs of infection include: fever, lethargy, enlarged lymph nodes, loss of appetite, weight loss and bleeding disorders.
• Anyone who suspects their dog has the disease should contact their private vet, a DPIRD vet or the Emergency Animal Disease hotline on 1800 675 888.