Bartonellae as elegant hemotropic parasites.

Bartonella species are hemotropic bacterial parasites of a wide range of mammals that occasionally cause disease in humans. The low prevalence of clinical manifestations compared to the high prevalence of infection underlines the elegance of these parasites that carefully exploit their hosts in a manner that optimizes their transmission. Recent research efforts have begun to determine the strategies involved in this exploitation, and significant progress has been made in unraveling an unusually complex natural cycle. Studies aimed at determining bacterial attributes involved in parasitism characterized several "virulence" factors and explored their modes of action. These efforts have provided an intriguing foundation on which future efforts aimed at comprehending these sophisticated parasites can be soundly based.