What is Rocky Mountain spotted fever?
Rocky Mountain spotted fever (RMSF) is a disease caused by Rickettsia rickettsii

How is RMSF spread?
In Connecticut, RMSF is transmitted to humans by the bite of an infected American dog tick, Dermacentor variabilis, or by contamination of the skin with tick blood or feces. Person-to-person spread of RMSF does not occur.

Who gets RMSF?
In the eastern United States (US), children are infected most frequently, while in the western US, disease incidence is highest among adult males. Disease incidence is directly related to the exposure to tick-infected habitats or to infested pets.

What are the symptoms of RMSF?
The disease is characterized by a sudden onset of moderate to high fever (which can last for 2 or 3 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.

How soon do symptoms appear?
Symptoms usually appear within 2 weeks of the bite of an infected tick.

Does past infection with RMSF make a person immune?
One attack probably provides permanent immunity.

How is RMSF diagnosed?
Diagnosis is confirmed by a blood test. 

What is the treatment for RMSF?
Certain antibiotics such as tetracycline or chloramphenicol may be effective in treating the disease.

How can RMSF be prevented?
To prevent RMSF and other tick-borne infections, the best protection is to avoid contact with ticks. When working or playing outside in areas that ticks inhabit (tall grass and weeds, shrubby areas, woods and leaf litter) you should:

  • Wear light colored clothing (to spot the ticks easily), long sleeved shirts and long pants.
  • Create a “tick barrier” by tucking pants into socks and shirt into pants.
  • Consider using insect repellent, according to manufacturer’s instructions, when planning to be outdoors.
  • Check clothing and skin very carefully (especially thighs, groin, arms, underarms, legs and scalp) after being outdoors in tick infested areas and remove any ticks promptly.
  • Wash the area with soap and water and apply an antiseptic when the tick has been removed.
  • Keep your lawn mowed, cut overgrown brush, and clear any leaf litter away from the home.
  • Inspect pets daily and remove any ticks found.

How should a tick be removed?

  • It is important that a tick is removed as soon as it is discovered.
  • Remove the tick as soon as possible using tweezers. Grasp the tick mouth parts as close to the skin as possible and pull the tick out with steady pressure. Do not yank the tick out. Do not crush the ticks body as it may contain infectious fluids.
  • Do not use petroleum jelly, hot matches, nail polish remover, or any other substance to remove a tick. By using these substances, you may actually increase your chance of infection.
  • Thoroughly wash the area of the bite with soap and water and put an antiseptic on it.
  • Check after every 2 to 3 hours of outdoor activity for ticks attached to clothing or skin.
  • The sooner the tick is removed, the lesser the risk of tick-borne infection.
  • Write on the calendar the date you removed the tick and the part of the body it was removed from.
  • Contact your physician for recommendations on testing and treatment.



This fact sheet is for informational purposes only. It should not be used for self-diagnosis or as a substitute for consultation with a health care provider. If you think that you may have this infection, or have questions about the disease described above, you should consult your health care provider.



For additional information on this disease, visit the Centers or Disease Control and Prevention website.

To contact the Epidemiology and Emerging Infections Program, please call 860-509-7994.