home / pet health + safety / healthy bytes / fetch! blog / another reason to beware of ticks: rocky mountain spotted fever
Default image

another reason to beware of ticks: rocky mountain spotted fever

  • Dr. Kim
  • Posted by Dr. Kim Smyth on
    Staff Veterinarian and Pet Health Writer of Petplan

How is Rocky Mountain spotted fever transmitted?


RMSF is carried by the wood tick, the American dog tick and the brown dog tick and is transmitted to your dog (or yourself!) through the tick’s bite. The tick has to be attached for five to 20 hours to transmit the disease-causing bacterial organism, Rickettsia ricketsii, so there’s no need to worry if you’re able to remove the tick early. This is a great reason to do a tick check on yourself and your loved ones (two- and four-footed) after coming in from the great outdoors.


Where is Rocky Mountain spotted fever most common?


Although RMSF has been reported in most states, it’s most commonly seen in the southern Atlantic and western central states, with some involvement in mid-Atlantic and southern New England states.


What are the signs of Rocky Mountain spotted fever in pets?


Clinical signs will show up two days to two weeks following a bite from an infected tick. The most consistent symptom of Rocky Mountain spotted fever is, as you might imagine, fever! It may be hard for owners to detect fever in their pet, but generally fever is accompanied by lethargy and decreased appetite.


Once transmitted, the bacterium invades and replicates inside the endothelial cells that line the walls of small veins and arteries. The inflammation it causes there is called vasculitis, and because every inch of your dog’s body contains blood vessels, every body system can be affected.


Clinical signs can range from mild to severe, and aside from fever, they include:

  • discharge from the eyes/nose
  • bloody nose
  • enlarged lymph nodes
  • skin lesions/sloughing
  • petechial hemorrhage, or pinpoint bleeding seen in the skin
  • non-specific pain
  • redness or swelling of mucous membranes
  • 1/3 of patients will show neurologic signs

How is Rocky Mountain spotted fever diagnosed?

Your dog’s veterinarian may suspect RMSF based on the clinical signs, but there are blood tests she can run to be sure. Often, a high antibody titer is found on presentation, but this isn’t always the case. A four-fold increase in titers over a two to three week period will confirm infection. Because time is of the essence in severely affected dogs, treatment is often initiated without definitive confirmation of the disease. In these cases, response to treatment can be enough to diagnose RMSF.


How is Rocky Mountain spotted fever treated?


Luckily, RMSF usually responds to treatment, and a reduction of clinical signs can be seen as soon as 24 hours after starting appropriate antibiotic therapy. Antibiotics should be continued until they are all gone (which may take a month), even if your pet is feeling better. For severe cases, blood transfusions and hospitalization may be required.



Because RMSF can be life threatening, it’s important to do your best to prevent it. With a myriad of parasite control options at your fingertips, there’s no excuse for not using flea and tick control. Go one extra step by performing a tick check after outings, and your furry friend will be fever free from spotted fever!

Add a comment here
  • *indicates required field

  • read more »
Email sent Close

Thanks for leaving a comment on this page. It will now be sent to our administrator for approval and should be added to this site shortly.

Posted by Ann Worden
on August 01 2016 10:50

Everything you read says "do a tick check" but what's the bast way to do it on a dog with longer hair? I feel for small bumps on my golden and border collie, but my mutt has a long and extremely thick coat. I have trouble just finding skin!

policies by AGCS Marine Insurance Company, an Allianz company

our bloggers
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
Dr. Ernie Ward, Jr.Veterinary Advisory Board of Petplan
vet tip of the week

Visit your vet at least once a year to keep your pet protected from preventable diseases.