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Rocky Mountain Spotted Fever (RMSF) is caused by a bacterium known as Rickettsia rickettsii
You can't catch RMSF from another person—you catch it from a tick bite
It is spread by the bite of the American dog tick. Ticks must be attached to the body for at least 4 to 6 hours before they pass RMSF bacteria to humans. Not every tick bite causes RMSF.
Symptoms appear 3 to 14 days after a tick bite
People with RMSF may have flu-like symptoms, high fever (above 101F), headache, nausea or vomiting, tiredness, stiff neck, joint pain, and swollen lymph nodes. After 3 to 5 days of symptoms, a red rash usually appears on the hands and feet and then spreads to the rest of the body. If the disease is not treated, it can cause death.
Anyone can get RMSF
People may be exposed when they spend time outdoors in tick-infested areas (such as wooded, brushy, or grassy places). Pets can bring ticks indoors and that may pose a risk to the household. RMSF is commonly seen during April through September, but can occur anytime during the year when there is warm weather.
Early diagnosis of RMSF is important. If you think you have RMSF, see your health care provider.
Early signs and symptoms of illness and a history of a tick bite help diagnose RMSF. Blood tests are available, but may be negative if done in the early stage of illness. If early blood tests are negative, a follow up test is recommended two to three weeks later.
RMSF can be treated with antibioticsCall your doctor if you think you have RMSF or if you feel sick after getting a tick bite.You can prevent RMSF
Household pets (dogs, cats) get RMSF and may carry ticks inside the home
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