Rocky Mountain Spotted Fever (RMSF)
Rocky Mountain Spotted Fever (RMSF) is an infection caused by the bite of an infected tick. It affects over 2,000 people a year in the U.S. and usually occurs from April until September, but it can occur anytime during the year where the weather is warm. The mid-Atlantic and southeastern states are most affected. The disease is spread to humans through a bite from an infected tick; it is not spread from one person to another.
In the U.S., the American dog tick (Dermacentor variabilis), the Rocky Mountain wood tick (Dermacentor andersoni), and the brown dog tick (Rhipicephalus sanguineus) have been identified as vectors that transmit the RMSF bacteria.
What are the symptoms of Rocky Mountain Spotted Fever?
The following are the most common symptoms of RMSF. However, each person may experience symptoms differently. Symptoms may include:
A non-itchy rash that usually starts on the hands, arms, feet, and legs and occurs seven to 10 days after the bite. The rash consists of flat, pink spots.
Nausea or vomiting
Sensitivity to light
RMSF is a serious illness that needs treatment as soon as possible. Death has occurred in untreated cases of RMSF.
Symptoms of RMSF may resemble other conditions or medical problems. Consult a doctor for diagnosis.
How is RMSF diagnosed?
Diagnosis is based on symptoms and past history of a tick bite. The appearance and character of the rash is important. Skin samples and lab tests (antibody titer, kidney function tests, platelet count, prothrombin time, partial thromboplastin time, urinalysis, and red blood cell count) are usually done to rule out other conditions and confirm the diagnosis.
What is the treatment for Rocky Mountain Spotted Fever?
Specific treatment for RMSF will be determined by your doctor and may include antibiotics (usually doxycyline until several days after the fever goes away) and supportive care.
How can Rocky Mountain Spotted Fever be prevented?
Once a person has RMSF, he or she cannot be reinfected. Some general guidelines for preventing RMSF include:
Since ticks cannot bite through clothing; dress your child and family in:
Long-sleeved shirts tucked into pants
Socks and closed-toe shoes
Long pants with legs tucked into socks
Check often for ticks on:
All parts of the body that bend: behind the knees, between fingers and toes, underarms, and groin.
Other areas where ticks are commonly found: belly button, in and behind the ears, neck, hairline, and top of the head.
Areas of pressure points, including:
Where underwear elastic touches the skin
Where bands from pants or skirts touch the skin
Anywhere else where clothing presses on the skin
All other areas of the body and hair. Run your fingers gently over the skin, and run a fine-toothed comb through your child's hair to check for ticks.
Other helpful measures include:
When possible, walk on cleared paths and pavement through wooded areas and fields.
Shower after all outdoor activities are over for the day. It may take up to four to six hours for ticks to attach firmly to skin. Showering may help remove any loose ticks.
Consider using insect repellents safely:
Products that contain DEET are tick repellents, but may not kill the tick and are not 100 percent effective. For children, use a children's insect repellent (20 to 30 percent DEET) and check with your child's doctor if your child is younger than age 1 before using.
Treat clothing with a product that contains permethrin, which is known to kill ticks on contact. Do not use permethrin on skin.
Check pets for ticks and treat as needed.
Last Reviewed Date: 08/30/2013
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