Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by a rickettsia (a microbe that differs somewhat from bacteria and virus).
Rocky Mountain spotted fever, form of tick-borne typhus first described in the Rocky Mountain section of the United States, caused by a specific microorganism (Rickettsia rickettsii). Despite the name, the disease is not limited to the Rocky Mountains but rather occurs throughout most of the U.S. It is spread by the bite of an infected tick. It can also be transmitted by contamination of the skin with tick blood or feces.
The bacteria Rickettsia rickettsii that causes RMSF is transmitted by the dog tick (Dermacentor variabilis) in the eastern United States and by the wood tick (Dermacentor andersoni) in the Rocky Mountain States. On the West Coast, the lone star tick (Amblyomma americanum) also can transmit the bacteria.
Children aged 5 to 9 are more likely to be infected than any other age group.
How it affects the body parts
Symptoms usually appear within two weeks of the bite of an infected tick. RMSF is characterized by a sudden onset of moderate to high fever (which can last for two or three weeks), severe headache, fatigue, deep muscle pain, chills and rash. The rash begins on the legs or arms, may include the soles of the feet or palms of the hands and may spread rapidly to the trunk or rest of the body.
Other symptoms that may occur with this disease:
When to Call a Doctor
Call the doctor immediately if you develop fever, headaches and nausea, with or without a rash, after you have been bitten by a tick or if you develop these symptoms and you have walked recently in tick-infested areas. The complications of untreated Rocky Mountain spotted fever are often life threatening.
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