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Home Topics Infectious Diseases Infections A-Z Bartonella


kitten image, courtesy Wikipedia

Organisms called Bartonella species are bacteria which can cause a variety of human illnesses ranging from benign lymph node enlargement to life-threatening systemic diseases. Of the ten Bartonella species believed to produce infections in humans, the most commonly encountered are Bartonella henselae, Bartonella quintana and Bartonella bacilliformis.

B. bacilliformis and B. quintana are present only in humans whereas other Bartonella species have been found in various animals including cats, dogs, and rats. Several insect vectors such as sand flies, human body lice, cat fleas, and ticks are or may be involved in transmission of infection.

Bartonella infections mostly occur worldwide, except B. bacilliformis which only exists in certain parts of South America.