PATHOLOGY

Detailed explanation-1: -Rickettsial infections and related infections (such as anaplasmosis, ehrlichiosis, and Q fever) are caused by an unusual type of bacteria that can live only inside the cells of another organism. Most of these infections are spread through ticks, mites, fleas, or lice.

Detailed explanation-2: -Rickettsiae are transmitted to humans by the bite of infected ticks and mites and by the feces of infected lice and fleas. They enter via the skin and spread through the bloodstream to infect vascular endothelium in the skin, brain, lungs, heart, kidneys, liver, gastrointestinal tract, and other organs (Fig.