Rocky Mountain Spotted Fever in Dogs

Rocky Mountain Spotted Fever (RMSF) is a tick-borne disease found in dogs across the United States. It may cause many symptoms, ranging from mild to potentially life-threatening. 

What is Rocky Mountain Spotted Fever in dogs?

This acute, tick-borne disease is caused by an intracellular parasite known as rickettsia rickettsii. An infected brown dog tick, Rocky Mountain wood tick or American dog tick can transmit RMSF to dogs, though an unfed tick must attach itself to your dog for more than 10 hours.

However, if a tick has already fed, it can transmit the disease in as little as 10 minutes after attaching. RMSF is found in dogs across the United States. Most often, cases are found in western central states, southern Atlantic states, southern New England coastal states and areas of the mid-Atlantic.

Signs & Symptoms of Rocky Mountain Spotted Fever in Dogs

Signs and symptoms of Rocky Mountain Spotted Fever will begin to appear between 2 to 14 days after biting your dog, though they may vary greatly.

Since many of these symptoms are also associated with other conditions, knowing if and when your pooch has been exposed to infected ticks can be very helpful to your vet in diagnosing your dog’s condition.

Common signs and symptoms of Rocky Mountain Spotted Fever include:

• Discharge from eyes/nose
• Reduced or poor appetite
• Lethargy
• Pain in joints or abdomen Diarrhea
• Cough
• Swelling in legs or face
• Vomiting
• Nosebleed
• Fever
• Lameness
• Enlarged lymph nodes

Up to one-third of dogs infected with the disease will experience symptoms related to central nervous system function, including balance problems, lack of voluntary coordination of muscle movements, weakness, spinal pain or seizures. In about 20 percent, you may also see tiny hemorrhages in their skin.

Any organ in your dog’s body can be affected by Rocky Mountain Spotted Fever, and symptoms can range from mild to severe, or even life-threatening.

How is Rocky Mountain Spotted Fever diagnosed?

Your veterinarian will look for any of the symptoms listed above and potentially complete a series of diagnostic tests including basic blood tests, x-rays and urinalysis.

Low numbers of red blood cells (anemia) and platelets, or abnormal complete blood count (CBC) or white blood cell counts can reveal Rocky Mountain Spotted Fever.

Other diagnostic tests may detect informal liver or kidney values, electrolyte abnormalities, low protein levels or abnormal calcium levels, which can increase the probability of being diagnosed with this condition.

How is this condition treated?

The most prescribed treatment for dogs diagnosed with Rocky Mountain Spotted Fever is antibiotics. Most dogs will respond to treatment within 24 to 48 hours. However, dogs suffering from severe cases of the disease may not respond to treatment at all.

The most common antibiotics include doxycycline, minocycline and tetracycline. In some cases, a blood transfusion for anemia or other supportive therapies may also be recommended.

What is the prognosis for Rocky Mountain Spotted fever?

If effectively diagnosed and treated early, the prognosis is generally good for RMSF, and few complications impede recovery. In many cases, a dog will have lifelong immunity after the infection has cleared.

However, dogs with more advanced cases of Rocky Mountain Spotted Fever may be at higher risk for complications such as kidney disease, vasculitis, neurological diseases and coagulopathies. In these cases, severe complications may arise and prognosis is less clear.

How can I prevent my dog from getting Rocky Mountain Spotted Fever?

Limit your dog’s exposure to ticks and areas where ticks congregate, especially during peak tick season, from March through October.

If your dog has visited areas known to have ticks, closely inspect him or her upon returning home, as the sooner a tick is removed after it attaches to your dog, the better your chance that this external parasite will not have had the opportunity to infect your pet.

Remember: To avoid being infected through scratches on your hand or open cuts, wear gloves when removing ticks. Keeping a tick removal tool handy can make removing ticks faster and safer for you and your dog - they are inexpensive and can be found at pet stores and vet’s offices.

Apply tick prevention medications year-round to help protect your dog against many tick-borne diseases, including Rocky Mountain Spotted Fever, Lyme disease, canine ehrlichiosis, or canine babesiosis.Contact your vet to learn more about how you can prevent parasites.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.