Rocky Mountain spotted fever

Rocky Mountain spotted fever is a bacterial infection transmitted by a tick. Without prompt treatment, Rocky Mountain spotted fever can cause serious damage to internal organs, such as your kidneys and heart.

Although it was first identified in the Rocky Mountains, Rocky Mountain spotted fever is most commonly found in the southeastern part of the United States. It also occurs in parts of Canada, Mexico, Central America and South America.

Early signs and symptoms of Rocky Mountain spotted fever include severe headache and high fever. A few days later, a rash usually appears on the wrists and ankles. Rocky Mountain spotted fever responds well to prompt treatment with antibiotics.

Symptoms Causes Risk factors Complications Prevention

Although many people become ill within the first week after infection, signs and symptoms may not appear for up to 14 days. Initial signs and symptoms of Rocky Mountain spotted fever often are nonspecific and can mimic those of other illnesses:

  • High fever
  • Chills
  • Severe headache
  • Muscle aches
  • Nausea and vomiting
  • Restlessness and insomnia

Rash is distinctive

The red, nonitchy rash associated with Rocky Mountain spotted fever typically appears a few days after the initial signs and symptoms begin. The rash usually makes its first appearance on your wrists and ankles, and can spread in both directions — down into the palms of your hands and the soles of your feet, and up your arms and legs to your torso.

A few people who are infected with Rocky Mountain spotted fever don't ever develop a rash, which makes diagnosis much more difficult.

When to see a doctor

See your doctor if you develop a rash or become sick after a tick bite. Rocky Mountain spotted fever and other infectious diseases carried by ticks can progress rapidly and may be life-threatening. If possible, take the tick along with you to your doctor's office for laboratory testing.

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