Cat Scratch Fever in Dogs & Cats [Signs, Prevention, & More]

A close-up of a paw of a cat to represent cat scratch fever or cat scratch disease

Cat scratch fever, also known as cat scratch disease (CSD), is a bacterial disease that affects cats, dogs, and people. Up to 30% of cats carry this bacterial disease, although not all will show symptoms for it. In comparison, dogs are more likely to show clinical symptoms of cat scratch fever, once infected. 

Note: In humans, cat scratch fever is commonly transmitted by a scratch or bite from an infected cat producing symptoms, such as a bump or pustule at the scratch or bite site, swollen lymph nodes, fever, and fatigue. Learn more about cat scratch fever in humans here: Cat Scratch Disease | Healthy Pets, Healthy People | CDC

As with any disease, cat scratch disease can cause serious complications, especially when an immunocompromised individual or pet is involved (e.g. elderly, has a chronic condition, etc.). 

Understanding the causes, symptoms, diagnosis, treatment, and prevention of cat scratch fever is crucial in maintaining the health of pets and the entire household. The following article sheds light on cat scratch disease in pets, how it’s diagnosed, and more. 

Close-up of a cat’s paws with claws which, if infected, can transmit cat scratch fever to people

What’s in This Guide? 

What is Cat Scratch Fever in Cats & Dogs? 

The term ‘cat scratch fever’ can be a bit misleading because cats are not the only ones that can be infected by this bacterial disease — people and dogs can be infected as well. In fact, cats are less likely to show clinical symptoms than dogs. 

Causes of Cat Scratch Fever

Cat scratch fever is primarily caused by the bacteria Bartonella henselae. In some cases, other species of Bartonella (B. clarridgeiae, B. koehlerae, B. vinsonii) have also been found to cause cat scratch fever. 

Cats and dogs commonly become infected with Bartonella bacteria through flea bites or exposure to infected flea feces. Though less common, scratches and bites from an infected cat can also spread the disease among other pet cats and dogs. (Scratches and bites from infected cats, however, are a common mode of CSD transmission to people.) 

Note: As for dogs, it is not known if they can transmit cat scratch fever to their pet parents or other pets.

Symptoms of Cat Scratch Fever

The following are common symptoms of cat scratch disease in pet dogs and cats: 

  • Fever
  • Swollen lymph nodes
  • Decreased energy levels
  • Loss of appetite
  • Reluctance to move too much due to sore muscles (commonly seen in dogs)

Note: As mentioned earlier, cats are less likely to show clinical symptoms of CSD. This means some cats can carry Bartonella without showing the above signs of illness. 

In some cases, cat scratch fever in pets can lead to more serious complications like deep eye inflammation and heart inflammation. Other systems of the pet's body can also be affected by a Bartonella infection, producing complications such as hepatitis, polyarthritis, anemia, etc. 

A dog that lost their appetite and is lethargic, some of the symptoms of cat scratch fever in dogs

Diagnosing Cat Scratch Fever in Pets

When diagnosing cat scratch fever, veterinarians begin with a physical exam. However, an exact diagnosis can be challenging as the symptoms can mimic those of other conditions. To conclusively diagnose cat scratch fever, veterinarians need laboratory testing — which can involve any of the following:

  • Detecting antibodies against Bartonella;
  • Detecting Bartonella DNA; or 
  • Bacterial culture using blood. 

Note: Licensed veterinarians are the only ones that can conclusively diagnose cat scratch fever in pets, using the techniques above. 

How to Treat Cat Scratch Disease in Dogs & Cats

For both dogs and cats that show symptoms of cat scratch fever, vet-prescribed antibiotics are needed for treatment. For dogs, antibiotics need to be administered for around 4-6 weeks. For cats, treatment generally takes 2-4 weeks.

It is important to note that these timeframes of treatment can change depending on a pet’s individual needs. In addition, veterinarians may also prescribe medication for pain relief, depending on the case. 

Note: For pets that have sustained more serious complications from cat scratch fever, hospitalization may be recommended. 

How to Prevent Cat Scratch Fever

Whether you’re looking to prevent cat scratch fever in people, cats, or dogs, the following preventive measures will help!

1. Have Regular Flea Control

The name ‘cat scratch fever’ must not distract pet parents from the fact that the flea is the vector insect that primarily causes the spread of this disease among pets. Therefore, maintaining regular flea control among pets is helpful in preventing cat scratch fever. Consult a veterinarian to get the best flea control strategies for your pet’s needs. 

2. Lessen the Likelihood of Cat Scratching Accidents

Keeping a cat’s nails trimmed helps minimize scratching accidents. In addition, providing appropriate, enriching outlets for energy (e.g. cat toys, scratch posts) will help minimize aggressive behaviors. 

Note: If your cat regularly displays aggressive behavior, we recommend getting a behavioral consultation with an experienced veterinarian. 

3. Be Mindful of Steps for First Aid

Even with preventive measures in place, cat scratch accidents can still happen — and when they do, please make sure to practice cat scratch first aid for both people and furry companions.

For more information on cat scratch first aid for people, here is a good reference to check out: What You Should Do for a Cat Bite or Scratch | Cleveland Clinic. 

If your furry companion sustained a cat scratch, here are the steps for applying first aid, as recommended by Sploot’s veterinarian, Dr. Allison Kihn: 

  1. Clean the wound with chlorhexidine (a disinfectant and antiseptic). In the absence of chlorhexidine, use soap and water. Make sure to AVOID using hydrogen peroxide or apple cider vinegar as these solutions will cause stinging. 
  2. Let the wound dry.
  3. If you have antibacterial ointment for pets, apply it on the site of the scratch.

Note: If you observe that the wound is deep, large, or will not stop bleeding, promptly reach out to an urgent care veterinarian.  

4. Take Extra Measures for Immunocompromised Individuals

For households with an immunocompromised or elderly Individual, it is highly recommended to do the following: 

  • Immediately after adoption, have your cat checked by a veterinarian. Apart from getting a thorough wellness exam for your new cat, it may also be helpful to discuss the pros and cons of bartonella testing with your veterinarian. Bartonella testing, if done proactively (i.e. without the cat showing symptoms), has nuances — including the possibility of false-negatives and the fact that it is not always beneficial in each case. 
  • Consider keeping a cat completely indoors if they belong to an immunocompromised person. This will help lessen the cat’s exposure to infected fleas. 
  • Strictly follow flea control measures all year round. Fleas spread the disease among pets and can, in some cases, also infect humans. 
  • Do NOT encourage biting or scratching behaviors in cats.
  • Do NOT allow the cat to lick open wounds.
A cat that is well-behaved and kept indoors, one of the ways to prevent cat scratch fever

How Long Do Cats Carry Cat Scratch Disease?

Once infected, a cat can carry cat scratch fever for months until the disease resolves by itself or (in some cases) resolves with the aid of treatment. 

Can Humans Get Cat Scratch Fever from Infected Dogs, Cats, & Fleas?

Humans are most likely to get cat scratch fever from infected cats. Infected dogs have not shown the capacity to transmit cat scratch disease to their pet parents or other pets. In some cases, Bartonella bacteria can also be transmitted to humans through vector insects like fleas, body lice, and sand flies

Final Thoughts on Cat Scratch Fever

By practicing preventive measures and seeking veterinary care when necessary, we can minimize the risk of cat scratch fever and promote the health of our beloved cats and dogs. As always, we encourage pet parents to consult a veterinarian for specific concerns or questions. For pet parents in Denver, we’re here to help!

Sploot Veterinary Care specializes in primary & urgent care for dogs and cats. If you have questions about cat scratch fever or flea prevention, our experienced veterinarians will be able to guide you on your next steps. Come on in any day of the week; our vet clinics are open for extended hours. You can also conveniently schedule an appointment online!

Till next time, we’re with you every pounce of the way!