Bartonella henselae

bacterium

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Last updated

July 16, 2026

Quick Summary

Bartonella henselae is a bacterium that causes cat scratch disease in humans. This infection is typically transmitted through a cat bite or scratch, and it is believed that cat fleas spread the bacterium between cats.1

Infected individuals usually experience self-limiting lymph node enlargement and do not require antibiotic treatment. However, some patients may develop severe health issues such as encephalopathy, endocarditis, or osteomyelitis. Individuals with compromised immune systems are particularly vulnerable to diseases transmitted by pets, including cat scratch disease. Practicing good hygiene when interacting with pets can significantly reduce the risk of infection.1

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cat scratch disease
…in human beings caused by Bartonella henselae, which is transmitted by a cat bite or scratch. Transmission of the bacterium from cat to cat is thought to be by the cat flea. The clinical syndrome in the infected person is usually a self-limiting enlargement of the lymph nodes not requiring…
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…in human beings caused by Bartonella henselae, which is transmitted by a cat bite or scratch. Transmission of the bacterium from cat to cat is thought to be by the cat flea. The clinical syndrome in the infected person is usually a self-limiting enlargement of the lymph nodes not requiring…
Read More