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Cat Scratch DiseaseCat

Cat scratch disease (CSD) is caused by a rickettsial organism, Bartonella henselae.  Most people contract CSD after a cat scratch or bite.  It can take seven to 20 days after the initial injury for symptoms to develop.  Infection is usually mild and characterized by a non-healing ulcer at the point of injury and swelling of nearby lymph nodes.  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 oculoglandular syndrome.  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.

Animals associated with cat scratch disease include:

  • Cats:  Kittens are more likely to be infected and to pass the bacterium to people.  About 40 percent 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.   
  • Fleas:  B. henselae has been found in fleas, and fleas are thought to be important for the spread of B. henselae from one cat to another.  There is, however, no evidence that a person can contract cat scratch disease from the bite of an infected flea.

Steps to reduce your risk of cat scratch disease:

  • Control fleas.
  • Avoid “rough play” with cats, especially kittens.  This includes any activities that may lead to bites or scratches.
  • Wash all cuts and bites immediately and thoroughly with soap and water.
  • Contact your healthcare provider if you develop an infection (with pus and pronounced swelling) where you were scratched or bitten by a cat or develop symptoms, including fever, headache, swollen lymph nodes and fatigue.

Cat scratch disease resources:


Last updated:  09/16/2014

Zoonotic Disease Program