Infections associated with Bartonella species in persons infected with human immunodeficiency virus.

Two members of the genus Bartonella, Bartonella quintana (formerly Rochalimaea quintana) and Bartonella henselae (formerly Rochalimaea henselae), have recently been recognized as agents of severe or fatal disease in patients infected with human immunodeficiency virus (HIV). The development of infection with B. henselae in HIV-infected individuals has been associated with traumatic contact with cats (scratches or bites), and domestic cats have been identified as a major reservoir for this organism. Specific information regarding the transmission of B. henselae to humans is not yet available, but common-sense precautions that minimize exposure to cat-associated organisms are appropriate. Preliminary accounts suggest that B. quintana infections are more common than B. henselae infections among HIV-infected individuals in San Francisco. The source of infection with B. quintana and the mechanism of its transmission remain unknown.