General Information: This strain was isolated in mice from an infected tick. Obligate intracellular bacterium and causative agent of heartwater. This organism causes heartwater, a disease with a high mortality rate that affects both wild and domesticated ruminants in sub-Saharan Africa and parts of the Caribbean. The name heartwater refers to the hydropericardium (excessive fluid in the sac surrounding the heart) commonly found associated with infection. This organism is found in membrane-bound vacuoles in endothelial cells and neutrophils and is an obligate intracellular parasite.