test

I recently wrote about a couple cases of Rocky Mountain Spotted Fever (RMSF) in dogs in Ontario. It’s not a disease we expect to find here, but we’re concerned about this tick-borne disease because it can be very nasty, and we do have the ticks for it. Ticks and the diseases they transmit are a evolving issue, especially with the impacts of climate change. We’re seeing more ticks and more disease, both in terms of numbers and ranges.

At the time, I pointed out the possible considerations for a situation where we’d found a small number (2) of unexpected cases in dogs. To recap:

It’s possible this current situation is:

  • A single unusual but precedented case, plus online chatter
  • A cluster of cases from a point source of exposure that will die out
  • One or a cluster of cases from exposure to infected adventitial ticks (i.e. ticks from high risk areas that dropped off traveling birds)
  • An indication that RMSF is emerging in some areas in Ontario

BUT now we’re up to 5 affected dogs. Four had a history of being at Long Point, Ontario, an area that has long been at the forefront of ticks and tickborne disease in Ontario. The other dog had more of a vague history, but may have been in that area too.

Whether it’s 4 or 5, that’s enough of a trend to suggest there might be a local focus in Long Point of ticks carrying Rickettsia rickettsii (the bacterium that causes RMSF, which is transmitted by certain ticks).

Obviously we need to investigate this more. It also means we need to be more aware of this disease and pay even more attention to the ticks. In Ontario, RMSF can be transmitted by the American dog tick, Dermacentor variabilis, which is well established here, but a different species from the tick that typically get the most attention, the black legged tick Ixodes scapularis, which is associated with transmission of Lyme disease.

For dog owners:

  • Be aware of the risk of tickborne diseases. For RMSF, be particularly aware if you spend time at Long Point.
  • Talk to your veterinarian about tick prevention medication.
  • Try to avoid high risk areas (e.g. lots of leaf litter, long grass).
  • Perform regular tick checks on your dog after being outside.
  • If your dog has been around Long Point and is sick, don’t be afraid to ask your veterinarian about the possibility of RMSF.

Also for dog owners:

  • Realize that if your dog is exposed to ticks, so you are (but you’re not on tick preventative medications). People can get RMSF too, and it can be serious.
  • If you are exposed to ticks and are sick, make sure your physician knows about your tick exposure and where you’ve been.
  • Perform regular tick checks on yourself after being outside.

For veterinarians:

  • Realize that we may have to consider RMSF in dogs that have not travelled outside Ontario.
  • Be prepared to test dogs that could have RMSF (PCR is the usual approach).

For physicians: