Rocky Mountain Spotted Fever

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Rocky Mountain spotted fever facts

  • Between 2005-2010, approximately 2,000 cases per year of Rocky Mountain spotted fever (RMSF) have been reported in the United States.
  • RMSF is a potentially serious tick-borne disease that can cause fatalities, and it is the most common cause of fatal tick-borne diseases in the United States.
  • The incidence of RMSF has increased from less than two cases per million people in the year 2000, to over six cases per million people in 2010.
  • Although RMSF cases have been reported throughout the United States, the highest incidence of cases in 2010 were in Arkansas, Delaware, Missouri, North Carolina, Oklahoma, and Tennessee.
  • RMSF is treatable with antibiotics, but it can have serious long-term effects and can potentially lead to death if not treated quickly and properly.

What is Rocky Mountain spotted fever?

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the bacterium Rickettsia rickettsii. This illness, which is found in North, Central, and South America, is transmitted via the bite of an infected tick. The illness affects the lining of blood vessels (causing a condition termed vasculitis), causing the blood vessels to leak, which ultimately can cause damage to nearly all internal organs. It is the most common cause of fatal tick-borne diseases in the United States.

Where do most cases of RMSF occur in the U.S.?

Cases of RMSF have been reported in many areas of the country, and the disease is not restricted to the Rocky Mountain region, as its name may imply. In fact, Arkansas, Missouri, North Carolina, Oklahoma, and Tennessee account for over 60% of reported cases. In 2010, there were approximately 2,000 cases reported in the U.S., which is more than twice as many cases reported annually in the 1990s.

Reported incidence of RMSF per million people in 2008
Reported incidence of RMSF per million people in 2008; NN=not reported. SOURCE: CDC.
Medically Reviewed by a Doctor on 9/1/2015

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Rocky Mountain Spotted Fever Slideshow

See pictures of the ticks that transmit Rocky Mountain spotted fever (RMSF). Plus, get tips on how to prevent RMSF.