Reviewed By: Pramod Kerkar, MD, FFARCSI

What is Cat Scratch Disease or Cat Scratch Fever?

Cat Scratch Disease (also known as Cat Scratch Fever) is a bacterial infection which is transmitted by cats. When an infected cat licks an individual's open wound or scratches or bites a person such that the skin breaks open then it leads to transmission of Cat Scratch Disease or Cat Scratch Fever from cats to humans. The bacterium which causes Cat Scratch Disease is Bartonella henselae. This bacterium lives in the saliva of the infected cat; however, it doesn't make the cat sick. In fact, cats and kittens can carry this bacterium for a long time without being sick. This bacterium gets spread between cats via fleas.

What is Cat Scratch Disease or Cat Scratch Fever?

What are the Symptoms of Cat Scratch Disease or Cat Scratch Fever?

  • The initial sign of Cat Scratch Disease or Cat Scratch Fever is a small bump or a blister which develops some days after the bite or a scratch of a cat and it resembles a bug bite. This bump or blister is also termed as inoculation lesion, which is a wound site through which the bacteria enter the body.
  • Lesions of cat scratch disease commonly are seen on the hands, arms, head or scalp. These lesions are not usually painful.
  • After a couple of weeks of a scratch or bite of the cat, there is development of swelling and tenderness in the adjacent lymph nodes, most commonly seen in the underarm or neck areas. If the inoculation lesion is present on the leg, then the lymph nodes in the groin are affected.
  • These affected lymph nodes range in size from about half-a-inch to 2 inches in width. These affected lymph nodes may also be surrounded by a larger area of swelling beneath the skin. The skin covering these swollen lymph nodes appears red and warm.
  • In most of the patients, the tender and swollen lymph nodes are the primary symptom of the cat scratch disease which is usually mild.
  • Other symptoms found in patients with cat scratch disease or cat scratch fever include fever, loss of appetite, fatigue, rash, headache, sore throat and general unwell feeling.
  • The swollen lymph nodes often resolve within 2 to 4 months; however, in some cases it can persist for a longer time.
  • Rarely, patient with cat scratch disease or cat scratch fever can develop other symptoms such as infections of the spleen, liver, bones, lungs, joints or a lingering high fever without other symptoms.

Serious Symptoms of Cat Scratch Disease or Cat Scratch Fever

  • If there is pain and swelling in the lymph nodes in any part of the body.
  • If the inoculation wound does not heal after the scratch/bite of the cat.
  • If the patient has persistent fever after the cat scratch or cat bite.
  • If there is an area of redness or rash around the inoculation wound that keeps increasing.
  • If the patient does not improve and continues to deteriorate.
  • If there is development of new symptoms.

How is the Diagnosis of Cat Scratch Disease or Cat Scratch Fever Made?

Cat Scratch Disease is often diagnosed based on the patient's history of exposure to kitten/cat and a physical examination. During the physical exam, the physician looks for signs of a cat bite/scratch and swollen lymph nodes to diagnose Cat Scratch Disease or Cat Scratch Fever. Blood tests and Blood cultures are done to exclude other causes of swollen lymph nodes. Blood tests are also done to diagnose cat scratch disease.

Is Cat Scratch Disease or Cat Scratch Fever Contagious?

Cat scratch disease or cat scratch fever is not contagious in the sense that it does not spread from one person to another. The bacteria of cat scratch disease get spread from the bite or scratch of an infected animal, mostly cat or kitten. Cat scratch disease or cat scratch fever also spreads when the infected animal's saliva comes in contact with a person's broken skin or a person's eye.

What is the Treatment of Cat Scratch Disease or Cat Scratch Fever?

  • Most of the patients do not need any specialized treatment for Cat Scratch Disease.
  • If the Cat Scratch Disease or Cat scratch Fever is severe, then antibiotics are prescribed which should be taken as per the doctor's instructions.
  • OTC medications like ibuprofen or acetaminophen can be prescribed for cat scratch disease can be given to ease the sore lymph nodes.
  • Patients with cat scratch disease need not be isolated from other family members.
  • Rest is important but not mandatory. If the patient suffering from Cat Scratch Disease is tiring easily then bed rest should be taken.

Does Cat Scratch Disease or Cat Scratch Fever Recur after Successful Treatment?

People who have had one episode of cat scratch disease often become immune for the rest of their lives to this disease.

How to Prevent Cat Scratch Disease or Cat Scratch Fever?

There is no need to get rid of your pet cat to prevent this disease. Cat Scratch Disease is a mild disease and is not a common condition. Following some precautionary measures helps in decreasing the chances of contracting this disease.

  • Always avoid touching or petting unfamiliar or stray cats/animals.
  • Avoid playing rough games with your pet so you can lower your chances of being bitten or scratched by your pet cat.
  • Always wash your hands thoroughly after playing with or handling a cat.
  • In case you are bitten or scratched by your pet, then wash the injured area immediately and thoroughly with water and soap.
  • It is important to keep your house and your pet free from fleas. This will cut down the risk of your pet cat becoming infected with the bacteria in the first place.
Pramod Kerkar

Written, Edited or Reviewed By:


Pain Assist Inc.

Last Modified On: April 5, 2018

This article does not provide medical advice. See disclaimer

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