New national veterinary guidelines on Canine ehrlichiosis (Ehrlichia canis)

The Australian Government has released new national veterinary guidelines on Canine ehrlichiosis (Ehrlichia canis). Biosecurity Queensland has updated the E. canis webpage and information for veterinarians on E. canis including assessment of suspect infections, laboratory diagnosis and treatment and links to the new guidelines. The first detection of E. canis in Australia occurred in May 2020 in the Kimberley region of Western Australia, followed by detections in Katherine in the Northern Territory in June 2020. 

In January 2022, the first case of E. canis infection in Queensland was confirmed in a dog in Mount Isa. Currently, areas where E. canis infections are known to be active include: 

• the entire Northern Territory
• the Kimberley, Pilbara, Gascoyne and northern Goldfields of Western Australia
• far northern South Australia – north of Port Augusta and throughout the APY (Anangu Pitjantjatjara Yankunytjatjara) lands
• northwest Queensland – local government areas of Mount Isa, Doomadgee, Cloncurry and Carpentaria.

Clinical signs in dogs can vary considerably depending on the phase of infection – acute, subclinical, and chronic. The most common signs include: 

• fever
• lethargy
• anorexia
• weight loss
• lymphadenopathy
• ocular and nasal discharges - including hyphaema, retinal haemorrhages and epistaxis
• haematological abnormalities - most commonly thrombocytopaenia +/- anaemia.

Infection with E. canis is a nationally notifiable disease. If you suspect the presence of E. canis infection in any dog in Queensland, you must report it to Biosecurity Queensland on 13 25 23 or contact the Emergency Animal Disease Watch Hotline on 1800 675 888. Dog owners and veterinarians in Queensland have a general biosecurity obligation to manage the risk of E. canis infection, including restricting movement of infected, suspected or in-contact dogs and undertaking diagnostic testing on suspected dogs or prior to movement. 

E. canis infection can be diagnosed by real-time polymerase chain reaction (PCR) and serological tests. Samples should be submitted to the Biosecurity Sciences Laboratory and be accompanied by a completed specimen advice sheet and the specimen advice sheet—Ehrlichia canis supplement. To prevent onward transmission, dogs known or suspected to be infected with E. canis should immediately be treated with a registered acaracide. Topically acting products that repel and kill ticks are recommended. Treatment of the dog’s home environment is also advised.