How to Test for Rocky Mountain Spotted Fever

Rocky Mountain spotted fever is the common name for a bacterial infection known scientifically as Rickettsia rickettsii. It's the most lethal rickettsial illness in the United States. Rocky Mountain spotted fever is transmitted to humans by ticks in the Dermacentor genus. It is diagnosed through a physical exam and blood tests.

Things You'll Need

• Blood sample
• Indirect immunofluorescence assay
• Labeling compound
• Ultraviolet light

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Instructions

• 1

  Observe the initial symptoms of Rocky Mountain spotted fever. The first signs of this illness are flu-like symptoms that include fever, chills and muscle aches. You may also experience other general symptoms such as confusion and headaches. These signs typically begin two to 14 days after you were bitten by the infected tick.

• 2

  Perform a physical exam of the patient. The next sign of Rocky Mountain spotted fever is usually the characteristic rash that occurs in about 80 percent of all patients. It begins at the wrists and ankles within a few days after the onset of fever and spreads to most of the body.

• 3

  Look for later signs of Rocky Mountain spotted fever. Symptoms of advanced illness include loss of appetite, diarrhea, hallucinations, nausea, unusual light sensitivity, extreme thirst and vomiting.

• 4

  Conduct standard laboratory tests for Rocky Mountain spotted fever. A blood sample may show a low platelet count, commonly defined as less than 100,000 platelets per cubic millimeter. A low concentration of sodium in the blood, commonly defined as less than 135 milli-moles per liter may occur in 30 percent of patients. Patients with Rocky Mountain spotted fever may also have elevated levels of liver enzymes.

• 5

  Perform an indirect immunofluorescence assay to confirm the diagnosis. Take a blood sample and add a labeling compound that will only attach itself to the antibodies for Rocky Mountain spotted fever. Expose this labeled sample to ultraviolet light. The antibodies can be identified by the glow produced by the labeling compound.