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Cat Scratch Disease (CSD)


Cat Scratch Disease (CSD), or cat scratch fever, is an acute infection caused by a bacteria, Bartonella henselae, that is transmitted from cats to humans as the result of a scratch or bite, or from the contact of cat saliva on broken skin or the eye.


CSD affects a higher percentage of children than adults due to higher exposure.

The infected animal usually shows no signs of carrying the bacteria.


Within a few days of a scratch or bite, one-third of patients with cat scratch disease will develop a bump or ulcer at the site. About one to three weeks later, fever, headache, fatigue and general malaise often occur. The local lymph nodes may become enlarged and tender, and may remain enlarged for months. Weight loss, sore throat and draining lymph nodes are symptoms which occur less commonly.

A rare complication of cat scratch disease is encephalitis. Encephalitis is a serious and sometimes life-threatening inflammation of the tissues of the brain and spinal cord.

Call the doctor or seek treatment immediately if the person has any of these symptoms:

  • Unusual looking spots or bruises on the skin
  • Red, draining eye (conjunctivitis)
  • Unusual pain anywhere on the body
  • High fever (over 103F)
  • Stiff neck
  • Severe headache
  • Change in consciousness
  • Severe vomiting


Diagnosis is usually based on the following:

  • History of being exposed to cats or kittens
  • A physical examination for signs of a cat scratch and swollen glands
  • Negative skin tests, blood tests and cultures to rule out other conditions with swollen glands as a symptom


CSD is usually self-limited and requires no specific treatment.

Home treatment may include applying a heating pad or hot water bottle to the swollen glands, giving acetaminophen for pain, body aches or fever over 101F, and avoiding injury to the swollen glands.

In patients with severe local pain or systemic symptoms, antibiotics may be necessary.


What are the symptoms to look out for?

Do you recommend treatment?

Can cat scratch disease recur?

These are some preventive measures that can be taken to avoid cat scratch disease in family members:

  • Avoid contact with stray kittens and cats
  • Avoid rough play where the animal may want to bite or scratch you as a response
  • Regularly de-flea cats
  • If scratched, wash the scratch and the surrounding area with soap and water immediately
  • If a kitten/cat is an indoor pet, consider getting them de-clawed
  • Wash your hands after playing with a cat