Be alert for signs of Rocky Mountain Spotted Fever

We are dedicating this blog post to the memory of our long-time customer, Harper. She was a beautiful Portuguese Water Dog who, in spite of everyone's best efforts, recently succumbed to the neurological effects of Rocky Mountain Spotted Fever. We know Harper would want to help protect other dogs.

We have become well aware of Lyme Disease. Although this is still the most prevalent tick-borne disease in our area, there are several other diseases carried by ticks. Rocky Mountain Spotted Fever (RMSF) is a tick-borne disease that can affect both humans and dogs. Note that RMSF is not contagious; in order to contract it, your dog (or you) must be bitten by an infected tick.

Despite the name, RMSF is not confined to the Rocky Mountain region. Its distribution covers the entire US and other countries. Although the incidence of RMSF in our area is currently low, there seem to be some indications that it may be increasing. Because of the rapid progression and potentially serious consequences of the disease, vigilance is advised. So, here is some information to help you know more about how to help keep your dog, and therefore your whole family, protected.

While Lyme disease is carried by the deer tick, RMSF in the Northeastern US is carried by the American dog tick. When not engorged, the American dog tick is larger than the deer tick, however after feeding (on blood) and becoming engorged, it can be hard to tell the difference in size. Also, when engorged, both types of ticks appear as a cream to greenish-grey color. One visible difference is that deer ticks have black legs and the legs of the American dog tick are reddish-brown. When not engorged, it is easier to differentiate between the deer tick and the American dog tick. Female American dog ticks have an off-white scutum (the shield-like section immediately behind the head), while the backs of the males have a mottled, off-white/brown coloration. Deer ticks have a dark brown scutum and a dark brown/reddish brown back. 

Symptoms of RMSF in dogs can be vague and non-specific, making it harder to identify. If you have found a dog tick on your dog, or if you think he may have been bitten, be on the lookout for one or more of these signs (usually appearing 2-14 days after being bitten); poor appetite, muscle or joint pain, fever, coughing, abdominal pain, vomiting, diarrhea, swelling of the face or legs, or depression. There may also be small hemorrhages in the eyes or gums, or nosebleeds. More advanced RMSF may cause neurological symptoms, such as wobbling when walking, or hypersensitivity to light or touch.

RMSP is treated with antibiotics, usually for 7-21 days. RMSF is difficult to diagnose, even with blood testing, but if it is suspected, your vet will want to start antibiotic treatment right away. It is important to be aware that early treatment is crucial, as RMSF can advance very rapidly and become debilitating, or even fatal. So, although these symptoms can be associated with more likely, less potentially severe conditions, it is best to alert your vet to them as soon as they appear. 

The best defense against RMSF and other tick-borne diseases is to:

  • reduce exposure to ticks as much as possible
  • use repellents and tick-preventative medications (these can be used in tandem)
  • carefully inspect your dog for ticks every time he has been out in the yard and especially if he has been in wooded areas
  • frequently inspect dog beds, harnesses, collars, leashes, etc.

For a list of other tick-borne diseases affecting dogs AKC Canine Health Foundation | Canine Tick-Borne Disease (

For a wealth of information on all things tick-related, including identification TickEncounter (


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