Rickettsial infections cause 30% moality due to ?

Ans. is 'a' i.e., Endothelial injury Rickettsial infections are associated with a high morbidity and moality. The moality rate can be as high as 20% of Rocky Mountain Spotted fever and 30% for epidemic typhus. On entry into the human body, the rickettsiae multiply locally and enter the blood. They become localized chiefly in vascular endothelial cells, which enlarge, degenerate and cause thrombus formation, with paial or complete occlusion of the vascular lumen. The overall pathological features of the rickettsial diseases are due to the damage of vascular endothelium.