Information for vets

PIRSA has completed surveillance in dogs (including blood and tick samples) to determine whether E. canis is present in South Australia.

Ehrlichiosis was detected in ticks collected from 2 dogs in the APY lands in January 2021. Further tick samples collected in February 2021 confirmed widespread infection of ticks across multiple communities in the APY lands.

The first known case of ehrlichiosis in a dog from the APY lands, in far north South Australia, was diagnosed in March 2021.

Notifiable disease reporting

Infection with ehrlichiosis is a notifiable disease in Australia. SA private veterinary practitioners are required to immediately report any suspicion of clinical cases, including the:

• home location
• travel history
• tick exposure
• tick control history.

For suspected E. canis cases based on laboratory findings and appropriate travel history or tick exposure, call the Emergency Animal Disease Hotline. Samples may need to be collected.

Please also call the laboratory if diagnostic results are needed urgently, otherwise results may be delayed: (08) 8202 3300

Ongoing surveillance by private veterinary practitioners

South Australian domestic and community dogs may be approved for testing at no charge to the owner or veterinarian. The dogs must show clinical signs consistent with E. canis infection and not originate from the APY lands.

Approval by a PIRSA veterinarian must be granted prior to any sample submission for E. canis testing, if costs are requested to be covered.

A manual platelet count on a fresh blood film is needed to assess the presence of thrombocytopaenia. This can be performed in-house or commercially and must be done prior to seeking sample submission approval.

On a well spread blood film where cells are distributed in a monolayer, platelets per high power field (using the 100x oil objective) should be counted. An average across 10 high power fields are then calculated.

An average of 12 to 15 platelets per 100x field (approximately 2.0 x 10⁵ platelets per µL) is considered normal. If there are less platelets present, the animal may have thrombocytopaenia.

Dogs tested for E. canis

Private veterinarians can submit samples from any domestic or community dogs for E. canis testing. However, if costs for testing are to be covered by PIRSA, then the animal must be clinically suspect for E. canis infection and approval must be sought from a PIRSA veterinarian prior to submission.

The likelihood of infection is increased where the dog has:

1. Clinical signs consistent with E. canis including:
   • thrombocytopaenia – this needs to be verified by manual examination of blood smears, and not by in-house laboratory results alone
   • unexplained fever or lethargy
   • blood from the nose
   • +/- swollen lymph nodes
   • +/- not eating.
2. A history of travel to regions with high tick numbers in northern SA or interstate.
3. A history of recent tick attachment or insufficient tick control program.

More information

• Ehrlichiosis disease in dogs – Northern Territory Government
• Ehrlichiosis in dogs – Department  of Agriculture, Fisheries and Forestry