What is Cat Scratch Fever?!

Estimated Reading Time 3 minutes
What is Cat Scratch Fever?!

Although pretty rare, cat scratch fever (CSF) is a serious infection in humans (usually children) that is typically caused by a bacteria found in some cats. Read on to learn more about the symptoms, treatment, and prevention of this strange disease.

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Please note: The following information is only meant to help you better understand what cat scratch fever is and how to avoid serious illness. This article is not meant to replace the advice of your doctor or medical professional. If you suspect that you have CSF, contact your physician right away.

Cause of Cat Scratch Fever

CSF is caused by the bacteria Bartonella henselae which is found on an estimated 30% of cats in the United States. Feral cats and especially kittens are the most frequent carriers. This is one reason why not petting these cats is a good idea and strict handwashing is important after handling them. Cats don’t usually get sick or show symptoms of Bartonella so there’s really no way to know if they’re carriers or not.

Bartonella can be transmitted to humans by a cat bite or scratch, or even from the saliva of an infected cat if it gets into an open wound or onto the surface of an eye. Rarely, it can also be transmitted by a flea or tick bite.

Signs of Infection

After transmission of the bacteria, there’s usually a raised, red bump or blister-like lesion at the bite or scratch site. It can take up to 10 days for this to develop.

Other common symptoms include:

  • Swollen and tender lymph nodes near the lesion (usually seen 1-3 weeks later)
  • Body aches
  • Fever
  • Fatigue

Diagnosis of Cat Scratch Fever

If suspected, it’s extremely important to have this infection properly diagnosed by a doctor or medical practitioner. A good history and physical exam may be all that’s needed to diagnose CSF. However, there is also a blood test that can be performed to confirm the diagnosis.

Treatment of Cat Scratch Fever

CSF usually doesn’t become serious, and some practitioners will choose to let it just “run its course” and resolve on its own. If treatment is needed; however, antibiotics will be prescribed for a few weeks. It’s important to know that some symptoms (especially swollen lymph nodes) will likely still be present after the antibiotics are finished. In fact, it may take several months for the lymph nodes to return to normal.

Preventing Cat Scratch Fever

Although most bites or scratches from your cat don’t result in CSF, if a bite or scratch does occur, wash the area vigorously with soap (preferably, anti-bacterial) and warm water for at least one minute. The CDC also recommends keeping your cat’s nails trimmed to help avoid scratches.

There is no vaccine for cat scratch fever, so the most important way to prevent it is for you and your pets to avoid contact with stray or feral cats and kittens. Again, strict hand washing is recommended if handling any stray cat is necessary or unavoidable.

Read more:

CDC - Cat-Scratch Disease

KidsHealth - Cat Scratch Disease

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Published: 12/18/2020
Last updated: 10/31/2021

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