Rocky Mountain spotted fever

Rocky Mountain spotted fever is caused by Rickettsia rickettsii, a species of bacteria that is spread to humans by hard ticks (Ixodidae). It was originally called “black measles” because of the characteristic rash that develops after infection.

Agent and vector

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  Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever.
• 
  Ixodes ricinus ticks

Symptoms

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  Hand and wrist displaying the characteristic spotted rash of Rocky Mountain spotted fever.
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  Close up of spotted rash.