Rickettsia is the agent for three major different branches of the sickness. 
  1. Typhone Fever: Also known as the epidemic Typhus. It is transmitted through lice and can be a potentially fatal disease. It is caused by the Rickettsia prowazekii bacterium. Although it is not particularly common in the United States, this disease has made a world-wide impact. 
  2. Rocky Mountain Spotted Fever: The disease transmitted by the Rickettsia rickettsii bacterium through ticks. This is the most common rickettsia-related disease in the United States. This is also a potentially fatal disease. 
  3. Q Fever: This is a zoonotic disease, which means that it is common in animals but can still infect humans. It affects the the most inhabitants of the United States with small amounts in other parts of the world. The bacterium that causes it is Coxiella burnetti. 

Coxiella Burnetti

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