Cat Scratch Disease in Humans

Cat scratch disease is relatively rare and typically mild.
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Cat scratch disease, commonly called cat scratch fever, is an infection caused by Bartonella henselae, a bacterium carried in the saliva of infected cats. According to the KidsHealth website, approximately 22,000 cases of cat scratch disease are diagnosed each year, usually in the cooler autumn and winter months.


Humans typically catch this infection through cat scratches, bites and exposure to cat saliva. Fleas spread the bacterial pathogens between felines, where it lives in the saliva. An infected kitty shows no signs of illness, but can still pass the pathogens on to people once she licks her paws and scratches skin. You might also contract this illness if you pet an infected cat and then rub your eyes.


Most individuals with cat scratch disease don’t have any symptoms at all, but some develop a mild infection at the bite or scratch site about 7 days after the saliva entered the broken skin. Some patients also experience swollen or tender lymph nodes within a week or two of the initial injury. Although less common, an infected person might also have flu-like symptoms, including fatigue, headache, lack of appetite, joint pain and a low-grade fever. Because those symptoms can also indicate other health issues, consult with your doctor to receive a professional diagnosis.

Diagnosis and Treatment

Doctors often diagnose cat scratch disease if you have a cat scratch or bite along with swollen lymph nodes, but some physicians confirm this diagnosis with a blood test. Most patients don’t require any treatment and get over the illness without any kind of medication.However, those with very painful or enlarged lymph nodes might be prescribed antibiotics to help clear up the infection. The initial injury site typically heels within one to three weeks to heel, while it might take between two and four months for node swelling to disappear.


Because this disease is so uncommon and the cases are typically mild, there is no need to give away your beloved family pet. You can easily avoid contracting cat scratch disease by washing licked, bitten or scratched skin with soap and water. Keep both your cat and your home flea-free to reduce the chances that your kitty will be infected with the bacteria that causes this infection.


Around 40 percent of all cats carry the B. henselae bacterium at one point in their lives. Both adults and kittens can cause the infection, but felines less than a year old are more likely to become infected and pass the bacteria on to humans. This illness is not contagious among humans, and fleas can't spread the infection from cats to humans. Most people only contract cat scratch disease once in their lifetime because they become immune to the bacteria.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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