Rocky Mountain spotted fever (RMSF) is a bacterial infection that's transmitted to people by tick bites. It occurs most often in the spring and summer, during months when ticks are active — between April and early September.
Although RMSF is most common in the southeastern part of the United States (Virginia, Georgia, and the Carolinas), it occurs in other states as well. It's relatively rare (about 250 to 2,000 cases per year in the United States), but can be a serious disease if not treated properly.
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.
RMSF gets its name from the trademark rash it causes — small red spots and blotches that begin on the wrists, ankles, palms, and soles. In addition to the rash, the infection can cause fever, chills, muscle aches, vomiting, and nausea. Typically, RMSF is treated with antibiotics and patients recover without any complications. But with late or no treatment, RMSF can cause serious health problems.
If your child has fever, achiness, stiff neck, or rash and has or may have been bitten by a tick, it's important to talk with your doctor.
The symptoms of RMSF typically develop within 1 week of a tick bite but can take up to 2 weeks to appear. In many cases, the person doesn't even remember being bitten by a tick.
Symptoms of RMSF usually begin suddenly. There is a high fever — often 103º-105ºF (39º-40ºC) — with chills, muscle aches, and a severe headache. Eyes can become red, muscles may feel tender, and there may be abdominal pain, nausea, vomiting, poor appetite, and fatigue.
The trademark rash of this infection can begin anytime up to 10 days after the fever and headache start, but it most often appears on the third to fifth day. The rash looks like small red spots or blotches that begin on the wrists, ankles, palms, and soles. It spreads up the arms and legs toward the trunk.
As the RMSF infection progresses, the original red spots might start to look more like bruises or bloody dots or patches under the skin.
Doctors usually diagnose Rocky Mountain spotted fever based on enough symptoms to indicate infection. Test results for RMSF can take a while to be sent to the doctor, so treatment often starts before the results are available.
RMSF is typically treated with oral or IV antibiotics, depending on the severity of the infection. Complications may require prolonged treatment.
If untreated, RMSF can lead to serious health problems, so it's important to call your doctor promptly if you notice any symptoms of RMSF, such as:
Without antibiotic treatment, RMSF can lead to health problems that involve the heart, lungs, and brain. In an extremely severe case, it can be fatal.
If your child is recovering from RMSF at home, follow the doctor's instructions for giving antibiotics. Allow your child to rest in bed until the fever and other symptoms are gone.
RMSF can be prevented by avoiding tick-infested areas, like woods and tall grasses, brush, shrubs, and low tree branches, and by taking precautions when spending time outdoors.
When they're playing outdoors, have kids wear light-colored clothing that makes ticks more visible and, if it's practical, long-sleeved shirts and long pants. Use an insect repellant that fends off ticks, being careful to follow the label instructions. Be sure to use a repellent that contains 10% to 30% concentration of DEET (look for N,N-diethyl-meta-toluamide).
Not all ticks carry the RMSF bacteria, but it's wise to remove any immediately. The longer a tick stays attached to the skin, the greater the chance of infection. It usually takes several hours for a tick to transmit the bacteria that cause RMSF once it has become attached to the skin.
To remove a dog tick, use tweezers to grasp it by the head (not just the body) as close to the skin as possible. Pull steadily until the tick dislodges. Without touching the tick, preserve it in a jar or plastic bag until you can show it to your doctor. Disinfect the bite area with alcohol, wash your hands, and call your doctor.
Since pets also can bring ticks into your home, check their skin and fur for ticks whenever they have been playing in tick-infested areas. Follow your veterinarian's advice about collars and other products that can be used to keep your pet tick-free.
If you have any concerns, talk with your doctor.
Reviewed by: Nicole A. Green, MD
Date reviewed: January 2014
|Centers for Disease Control and Prevention (CDC) The CDC (the national public health institute of the United States) promotes health and quality of life by preventing and controlling disease, injury, and disability.|
|National Park Service This site contains information on America's national parks and the many ways you can enjoy the great outdoors.|
|Camping and Woods Safety Ah, the great outdoors! Find out how to stay safe while you're exploring the woods.|
|How Can I Protect My Family From Ticks? Find out what the experts say.|
|First Aid: Tick Bites While most tick bites are harmless and don't require medical treatment, some ticks do carry harmful germs. Find out what to do if your child is bitten by a tick.|
|Evaluate Your Child's Lyme Disease Risk Does the threat of Lyme disease make you think your kids would be safer in your living room than in the great outdoors? Find out how to evaluate a child's Lyme disease risk.|
|Lyme Disease Lyme disease can affect the skin, joints, nervous system, and other organ systems. If diagnosed quickly and treated with antibiotics, Lyme disease in kids is almost always treatable.|
|Bug Bites and Stings In most cases, bug bites and stings are just nuisances. But in some cases, they can cause infections and allergic reactions. It's important to know the signs, and when to get medical attention.|
|Woods and Camping Safety for the Whole Family A family camping trip can be an enjoyable experience with a little preparation.|
|Bug Bites and Stings Generally, insect bites and stings are harmless. Find out how to keep pests from ruining your fun.|
|Lyme Disease The best way to prevent Lyme disease is to prevent tick bites. Find out more about this disease and how to keep those ticks away.|
|Lyme Disease Lyme disease can be treated if it's caught early. So read this to find out what causes it, how it's treated, and how to prevent it.|
|Hey! A Tick Bit Me! A tick attaches itself to the skin of a person or animal and sucks blood. If you have a dog, it may have picked up a tick before! Learn more about ticks in this article for kids.|
|What to Do When You're Bugged by Bugs Ugh. Bugs. They're cool, but they also can ruin your day by stinging or biting you. Find out how to handle them in this article.|
|Rocky Mountain Spotted Fever Rocky Mountain spotted fever (RMSF) is a disease caused by a bacteria that is carried by certain types of ticks. Learn about the signs and symptoms of RMSF and tips for preventing infection in this article.|
What to expect when coming to Akron Children's
For healthcare providers and nurses
Residency & Fellowships, Medical Students, Nursing and Allied Health
For prospective employees and career-seekers
Our online community that provides inspirational stories and helpful information.