Rocky Mountain Spotted Fever

Rocky Mountain Spotted Fever Summary
Rocky Mountain spotted fever (RMSF) is an infectious disease that's transmitted by the bite of a tick infected with the Rickettsia rickettsii bacterial organism. Initial symptoms of RMSF include fever, nausea, vomiting, muscle pain and severe headache. Later symptoms include rash, abdominal pain, joint pain, and diarrhea. Treatment usually involves a tetracycline antibiotic.
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Rocky Mountain spotted fever (RMSF) facts

  • Rocky Mountain spotted fever is caused by the bacterium Rickettsia rickettsii.
  • The bacterium is spread to humans through the bite of infected ticks, and so the disease is most common in months where ticks are active, such as summer.
  • Despite the name, the disease occurs throughout most of the U.S.
  • Symptoms of headache, fever, and fatigue begin about a week after exposure. A few days later, a rash develops. The rash may be so mild that it is hard to see or so dramatic that it progresses to gangrene. Other possible symptoms include confusion, abdominal pain, and vomiting.
  • Most cases require hospitalization, and severe cases require intensive care.
  • The disease is diagnosed by finding high titers of antibodies in the blood or by seeing the organism under a microscope in specially stained skin biopsies.
  • The treatment of choice is the antibiotic doxycycline (Vibramycin, Oracea, Adoxa, Atridox). Prompt treatment improves survival and reduces complications.
  • Most people with RMSF recover completely over a few weeks. In severe cases, patients may have brain damage or other neurological problems that persist after treatment.
  • The risk of RMSF can be reduced by reducing exposure to ticks. This includes avoiding areas that have large concentrations of ticks, using insect repellents and wearing protective clothing.
  • Because the risk of infection increases with the duration of tick attachment, people should check themselves for ticks when they return from an outing.
Medically Reviewed by a Doctor on 4/30/2014

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Rocky Mountain Spotted Fever - Location Question: Please share your experience with RMSF, including the region in which you contracted it.
Rocky Mountain Spotted Fever - Symptoms Question: What were your signs and symptoms associated with RMSF?
Rocky Mountain Spotted Fever - Diagnosis Question: What tests or methods were used to detect and diagnose your case of RMSF?
Rocky Mountain Spotted Fever - Treatment Question: What kinds of treatment or medication did you receive for RMSF?
Rocky Mountain Spotted Fever - Prevention Question: If you live in a region with ticks or previous outbreaks of RMSF, how do you try to prevent it?