Rickettsial infections cause 30% mortality due to -

Ans. is 'a' i.e., Endothelial injury o Rickettsial infections are associated with a high morbidity and mortality.o The mortality' rate can be as high as 20% of Rocky Mountain Spotted fever and 30% for epidemic typhus,o 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 partial or complete occlusion of the vascular lumen.o The overall pathological features of the rickettsial diseases are due to the damage of vascular endothelium.