While it’s unlikely that any given patient will have a rare disease, we need to remain vigilant for such conditions because they’re easy to miss. That’s just common sense – if we rarely see something, it doesn’t jump to mind when examining a patient. Babesiosis is one such disease. It’s seen commonly in some regions, but it’s really rare in Ontario.
Babesiosis in dogs is caused by a variety of species of Babesia, a group of blood parasites spread by a variety of ticks. Canine babesiosis is primarily spread by Rhipicephalus sanguineus (brown dog tick) and sometimes Dermacentor variablis (American dog tick). (Human babesiosis is caused by a different Babesia species that is primarily transmitted by Ixodes scapularis (deer tick, the same tick species that transmits the agent of Lyme disease).) Canine babesiosis is common in various parts of the world that are typically warmer than here (our forecast is calling for 15-20 cm of snow tomorrow). But, the ticks are present here and their range is increasing (and so is the range of the diseases they bring with them).
The March 2016 edition of the University of Guelph Animal Health Laboratory’s Newsletter has a case report of babesiosis in a puppy. It was diagnosed during necropsy (autopsy) of a 10 week old puppy that died of apparent hemolytic anemia (breakdown of red blood cells within the body). The puppy died during importation (i.e. in transit) from the Dominican Republic – another example of the problems that can occur with importation (particularly importation of young dogs with presumably little pre-importation examination). The age of the puppy is also noteworthy since it would not have been vaccinated against rabies – another example of Canada’s lax importation rules and importers’ questionable sense.
Would this puppy have posed a risk to others in Ontario if it had survived? Maybe, it’s hard to say. This Babesia species is mainly transmitted by Rhipicephalus sanguineus (the brown dog tick), a tick that is present in Ontario. If an infected dog is bitten by one of those ticks, it can introduce Babesia to the area.
Babesia is probably a parasite that we’re going to see more of with climate change and tick movement, so local veterinarians and dog owners need to have some awareness. Cutting down on illogical importation practices wouldn’t hurt either.