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Bartonella is a Gram-negative pathogen that is unique among bacteria in being able to induce angioproliferative lesions. Cultured human endothelial cells have provided an in vitro system in which to study the basis of angioproliferation. Previous studies have attributed the organism's ability to induce angioproliferative lesions to direct mitotic stimulation of endothelial cells by these bacteria. Here we show that Bartonella inhibits apoptosis of endothelial cells in vitro, and that its ability to stimulate proliferation of endothelial cells depends to a large extent on its antiapoptotic activity. Bartonella suppresses both early and late events in apoptosis, namely caspase activation and DNA fragmentation, respectively. Its ability to inhibit death of endothelial cells after serum starvation can be recapitulated by media conditioned by bacteria, indicating that direct cell contact is not necessary. Among tested strains, the activity is produced only by Bartonella species that are significant human pathogens and are associated with angioproliferative lesions. We suggest that endothelial cells normally respond to infection by undergoing apoptosis and that Bartonella evolved the antiapoptotic activity to enhance survival of the host cells and therefore itself. We propose that Bartonella's antiapoptotic mechanism accounts at least in part for its ability to induce vascular proliferation in vivo. Bartonella are unique among bacterial pathogens in their ability to cause angioproliferative lesions (1-3). These lesions are comprised of proliferating endothelial cells admixed with bacteria and can be found in many organs of the body. The disease process has been named bacillary angiomatosis when Bartonella henselae and Bartonella quintana are present. In the liver and spleen, the lesions can assume a cystic form referred to as bacillary peliosis. Bacillary angiomatosis and peliosis occur exclusively in immunocompromised patients, predominantly affecting patients with AIDS, and can be life-threatening.In immunocompetent individuals, B. henselae and B. quintana cause ''cat-scratch disease'' and ''trench fever'' (1-3). These prolonged febrile illnesses are associated with infection in blood and tissues that may last for months and can result in infection and destruction of heart valves. Approximately 20,000 cases of cat-scratch disease occur a year, with an estimated 2,000 requiring hospitalization. Trench fever predominantly affects homeless alcoholics but in the past was responsible for an epidemic of over 1 million cases during World War I. An additional species, Bartonella bacilliformis, causes disease in immunocompetent individuals within a geographically confined region in South America. This infection is associated with red cell destruction, immune suppression, and multiple angioproliferative skin lesions. Cat fleas, body lice, and sand flies serve as vectors for human infection by B. henselae, B. quintana, and B. bacilliformis, respectively.In these disease states, Bartonella has been found associated with endothe...

Introduction:Physicians and nurses are integral components of the public health bioterrorism surveillance system. However, most published bioterrorism preparedness surveys focus on gathering information related to selfassessed knowledge or perceived needs and abilities.Objective:A survey of physicians and nurses in Hawaii was conducted to assess objective knowledge regarding bioterrorism agents and diseases and perceived response readiness for a bioterrorism event.Methods:During June and July 2004, an anonymous survey was mailed up to three times to a random sample of all licensed physicians and nurses residing in Hawaii.Results:The response rate was 45% (115 of 255) for physicians and 53% (146 of 278) for nurses. Previous bioterrorism preparedness training associated significantly with knowledge-based test performance in both groups. Only 20% of physicians or nurses had had previous training in bioterrorism preparedness, and <15% felt able to respond effectively to a bioterrorism event. But, >70% expressed willingness to assist the state in the event of a bioterrorist attack.Conclusions:Additional bioterrorism preparedness training should be made available through continuing education and also should become a component of both medical and nursing school curricula. It is important to provide the knowledge necessary for physicians and nurses to improve their ability to perform in the event of a bioterrorist attack.

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