Cat Scratch Disease
(Bartonella henselae Infection)

Cat scratch disease facts*

*Cat scratch disease facts by

  • Cat scratch disease (CSD) is a bacterial disease caused by Bartonella henselae.
  • It is often caused by a bite or scratch from a cat. Kittens are more likely to pass on the bacteria.
  • Symptoms of cat scratch disease include swollen lymph nodes, fever, headache, fatigue, and loss of appetite.
  • To reduce your risk of getting CSD avoid rough play with cats and kittens, wash cat bites and scratches thoroughly, and contact your physician if you develop any symptoms following a cat bite or scratch.

What is cat scratch disease?

Cat scratch disease (CSD) is a bacterial disease caused by Bartonella henselae. Most people with CSD have been bitten or scratched by a cat and developed a mild infection at the point of injury. Lymph nodes, especially those around the head, neck, and upper limbs, become swollen. Additionally, a person with CSD may experience fever, headache, fatigue, and a poor appetite. Rare complications of B. henselae infection are bacillary angiomatosis and Parinaud's oculolandular syndrome.

Can my cat transmit Bartonella henselae to me?

Sometimes, yes, cats can spread B. henselae to people. Most people get CSD from cat bites and scratches. Kittens are more likely to be infected and to pass the bacterium to people. About 40% of cats carry B. henselae at some time in their lives. Cats that carry B. henselae do not show any signs of illness; therefore, you cannot tell which cats can spread the disease to you. People with immunocompromised conditions, such as those undergoing immunosuppressive treatments for cancer, organ transplant patients, and people with HIV/AIDS, are more likely than others to have complications of CSD. Although B. henselae has been found in fleas, so far there is no evidence that a bite from an infected flea can give you CSD.

Medically Reviewed by a Doctor on 4/1/2014

Patient Comments

Viewers share their comments

Cat Scratch Disease - Experience Question: Please describe your experience with cat scratch disease.
Cat Scratch Disease - Reducing Risk Question: In what ways do you try to prevent your cats from scratching people?
About 40% of cats carry Bartonella henselae, the bacteria that causes cat scratch disease.

What Is Cat Scratch Disease?

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: Barbara K. Hecht, PhD

Cat scratch disease is an infection caused by bacteria known as Bartonella henselae. Although about 40% of cats carry the bacteria in their saliva at some point in their lives, cats that carry Bartonella henselae do not themselves show any signs of illness. Most people contract the disease after being scratched or bitten by a cat.

Since these bacteria may also be present on cat fur, it is possible to contract the disease from petting a cat and then rubbing your eyes. Kittens are more likely than older cats to carry the bacteria and to transmit the infection to humans. Sometimes people who get cat scratch disease do not recall ever being scratched or bitten by a cat.

In people who have a normal immune system, cat scratch disease is usually not a serious illness. A small papule(a little raised lump) develops at the site of injury within 10 days. The signs and symptoms that follow may include...