The ‘other’ epidemic: canine ehrlichiosis in Australia
Peter Irwin A * and John Beadle BA Vector and Waterborne Pathogens Research Group, School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA 6150, Australia.
B All Creatures Veterinary Hospital Broome, PO Box 1752, Broome, WA 6725, Australia.
Peter Irwin is Emeritus Professor at Murdoch University. He has been studying tick-borne diseases of companion animals and wildlife for >30 years. |
John Beadle is a veterinarian and owner of a general practice in Broome, WA. His interests are 4WD remote camping, photography, cycling, yoga, orthopaedic surgery, astronomy, skiing, and hiking. |
Microbiology Australia 43(4) 156-159 https://doi.org/10.1071/MA22053
Submitted: 30 October 2022 Accepted: 1 December 2022 Published: 16 December 2022
© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the ASM. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)
Abstract
Canine monocytic ehrlichiosis (Ehrlichia canis infection) is a serious tick-transmitted disease of dogs that was considered exotic to Australia until recently. The disease was first reported across northern and central Australia in 2020, with significant canine morbidity and mortalities observed at indigenous communities where dog numbers are high, ticks are superabundant, and tick prevention is scant. The date and location of the incursion are unknown, yet comparative genomic analysis suggest the Australian E. canis may have originated from Asia or the Middle East. Veterinarians nationwide are on alert for this notifiable disease since cases have been reported in southern locations as a consequence of moving infected dogs from endemic areas. Acute infections in dogs respond favourably to doxycycline therapy, however chronic disease results in bone marrow failure and death. Tick prophylaxis is key to preventing canine ehrlichiosis and is best achieved using products that repel and kill ticks before they attach. Although reports exist of E. canis as a zoonosis, there is no evidence that the strain involved in the current Australian outbreak poses risk to humans.
Keywords: canine, dog, Ehrlichia, Ehrlichia canis, Rhipicephalus linnaei, Rhipicephalus sanguineus, tick, vector-borne disease.
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