Rocky Mountain spotted fever (RMSF) is a bacterial disease spread through the bite of an infected tick. Most people who get sick with RMSF will have a fever, headache, and rash. RMSF can be deadly if not treated early with the right antibiotic.

Avoid ticks

There is no vaccine for RMSF. The first step for preventing this devastating disease is to prevent tick bites.

Remove ticks

If you find a tick attached to your skin, there’s no need to panic—the key is to remove the tick as soon as possible.

Where ticks live

Not all ticks bite and transmit disease to people. 

Do you know about Rocky Mountain spotted fever (RMSF), the most deadly tickborne disease in the world?

Rocky Mountain spotted fever (RMSF) is a serious, sometimes deadly, bacterial disease spread through the bite of an infected tick.

• Roughly 4,000-6,000 tickborne spotted fevers, including RMSF, are reported in the United States each year.
• More than 60% of reported RMSF cases occur in five states (North Carolina, Tennessee, Oklahoma, Arkansas, and Missouri).
• While the majority of RMSF cases occur during summer months, ticks can still bite you during the spring, fall, or even year-round in warmer climates.

Signs and Symptoms

Early signs of RMSF are often non-specific with symptoms such as fever and headache. RMSF can progress to a serious and life-threatening illness in days. Early signs and symptoms may include:

• Fever
• Headache
• Rash, usually occurs around days 2-5
• Nausea, vomiting
• Stomach pain
• Muscle pain
• Lack of appetite

Treatment

• Doxycycline is the treatment of choice for adults and children of all ages with suspected RMSF as recommended by the CDC and the American Academy of Pediatrics.
• If treated in the first 5 days with doxycycline, people with RMSF typically recover. While those treated after day 5 of illness may experience a more severe illness requiring hospitalization, or intensive care.
• When left untreated, the bacteria can cause damage to blood vessels throughout the body leading to organ and tissue damage.
• RMSF can be fatal, even in previously healthy people. If not treated correctly, death can often occur within eight days of symptoms starting.
• People who do recover from serious RMSF infections may be left with life-altering damage, including amputation of arms, legs, fingers, or toes (from lack of blood flow), hearing loss, paralysis, or mental disability.

Diagnosis and Testing

• Diagnosis is made by a healthcare provider based on a person’s signs, symptoms, and possible exposure to ticks.
• Your healthcare provider may order certain blood tests to look for evidence of RMSF. Results may take weeks.
• Treatment with doxycycline should never be delayed while waiting for diagnostic test results.

Prevent RMSF. Protect yourself, your family, and your pets from tick bites.

• No vaccine to prevent RMSF is available. Prevent infection by preventing tick bites.
• Ticks live in grassy, brushy, or wooded areas, or even on animals.
• Spending time outside camping, gardening, or hunting can bring you in close contact with ticks.

Before You Go Outdoors

Know where ticks live. Ticks prefer moist and humid environments, particularly in or near wooded or grassy areas. You may come into contact with ticks during outdoor activities, around your home, or when walking through leaf litter or near shrubs. Always walk in the center of trails in order to reduce the chance of contacting ticks.

Use Environmental Protection Agency (EPA) registered insect repellent on skin.

• Use insect repellents containing DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone to repel ticks for several hours.
• The EPA has an online tool to help you select the repellent that is best for you and your family.
• Always follow product instructions.
• Parents should apply these products to their children, avoiding the hands, eyes, and mouth.
  • Do not use insect repellent on babies younger than 2 months old.
  • Do not use products containing OLE or PMD on children under 3 years old.

Treat clothing and gear with permethrin. Permethrin kills ticks and can be used to treat boots, clothing, and camping gear. Clothing treated with 0.5% permethrin will provide lasting protection even after several washings.

Treat your pets for ticks. Dogs are highly susceptible to tick bites and tickborne diseases.

• A variety of tick prevention products are available including tick collars, sprays, and oral medications.
• Use tick prevention products for animals regularly to protect your dogs and family from tick bites.
• Cats are extremely sensitive to many chemicals. Do not apply any insecticides, tick products, or insect repellents to your cat without first talking to your veterinarian!
• Talk to your veterinarian about the best choice of tick prevention product for your pet.

After You Come Indoors

Check your clothing and gear for ticks. Ticks can ride into the home on clothing and pets. Remove ticks if you find them.

• Tumble dry clothes in a dryer on high heat for 10 minutes to kill ticks on dry clothing after you come indoors.
• If the clothes are damp, additional time may be needed. If the clothes require washing first, hot water is recommended. Cold and medium temperature water will not kill ticks effectively.

Check your dogs for ticks after returning from tick habitats. The most common location for ticks on dogs include the ears, armpits, groin, around the paws, and in-between the toes.

Bathe or shower as soon as possible after coming indoors (preferably within two hours) to wash off and more easily find ticks that are crawling on you.

Check your body for ticks after being outdoors. Check your body for ticks! If you have kids, check them for ticks. Use a mirror or have someone help you with hard-to-see areas. Ticks can be found anywhere, but are commonly found:

What to Do if You Find an Attached Tick

• Remove any attached ticks from people or pets immediately.
• To remove a tick, grasp it with tweezers as close to the skin as possible, and pull it straight out. Do not twist or jerk. For detailed information about tick removal, see the Tick Removal page.
• Watch for signs of illness in people and pets after spending time in tick habitats, even if you don’t remember a tick bite. Remember, RMSF and other tickborne diseases can be treated effectively with doxycycline if caught early.
• See your healthcare provider immediately if you develop a fever, rash, or flu-like symptoms. Be sure to tell your healthcare provider if you were recently bitten by a tick or enjoy outdoor activities where you might have been in contact with ticks.

Fact or Fiction?

If you get RMSF, you will always develop a rash.
FALSE. While most people do develop a rash at some point during their illness, this may not occur until a person has been sick for many days. If you develop a fever or rash after spending time in tick habitats, see a healthcare provider immediately.

I don’t remember being bitten by a tick, so my illness can’t be caused by an infected tick.
FALSE. Tick bites are painless and often go unnoticed. In fact, only 6 in 10 people who got RMSF remember a tick bite.

Doxycycline can’t be given to children because it may stain their teeth.
FALSE. Doxycycline is the treatment of choice for people of all ages who are suspected of having RMSF. Recent studies have shown that doxycycline does not cause tooth staining when used in short courses (like those used to treat RMSF).

Rocky Mountain spotted fever is a serious tickborne illness which can be deadly if not treated early. It is spread by several species of ticks in the United States, including the American dog tick (Dermacentor variabilis), Rocky Mountain wood tick (Dermacentor andersoni), and, in parts of the southwestern United States and Mexico, the brown dog tick (Rhipicephalus sanguineus). RMSF cases occur throughout the United States, but are most commonly reported from North Carolina, Tennessee, Missouri, Arkansas, and Oklahoma.

Early signs and symptoms are not specific to RMSF (including fever and headache). However, the disease can rapidly progress to a serious and life-threatening illness. See your healthcare provider if you become ill after having been bitten by a tick or having been in the woods or in areas with high brush where ticks commonly live.

Signs and symptoms can include:

• Fever
• Headache
• Rash
• Nausea
• Vomiting
• Stomach pain
• Muscle pain
• Lack of appetite

Rash

Rash is a common sign in people who are sick with RMSF. Rash usually develops 2-4 days after fever begins. The look of the rash can vary widely over the course of illness. Some rashes can look like red splotches and some look like pinpoint dots. While almost all patients with RMSF will develop a rash, it often does not appear early in illness, which can make RMSF difficult to diagnose.

Long-term Health Problems

• RMSF does not result in chronic or persistent infections.
• Some patients who recover from severe RMSF may be left with permanent damage, including amputation of arms, legs, fingers, or toes (from damage to blood vessels in these areas); hearing loss; paralysis; or mental disability. Any permanent damage is caused by the acute illness and does not result from a chronic infection.

• The signs and symptoms of RMSF are similar to those of many other diseases. See your healthcare provider if you develop any of the signs or symptoms of RMSF.
• Be sure to tell your healthcare provider if you become ill and have recently been bitten by a tick or have spent time in areas where ticks may be found.
• Your healthcare provider may order certain blood tests to look for evidence of RMSF.
• The results of these tests can take weeks. If your healthcare provider thinks your illness might be RMSF, he or she should recommend antibiotic treatment before test results are available.

• RMSF can be life-threatening.
• Early treatment with the antibiotic doxycycline can prevent death and severe illness.

Doxycycline is the recommended antibiotic treatment for RMSF in adults and children of all ages.

RMSF is spread by the bite of an infected tick.

RMSF symptoms include a fever with

• Headache
• Upset stomach
• Rash (may occur later in illness)

See your healthcare provider immediately if you develop a fever

• after being bitten by a tick
• after spending time in areas with ticks

Remember, you may not know you have been bitten by a tick.

Doxycycline saves lives!

• Best treatment for suspected RMSF in children and adults
• Treatment needed early when RMSF is suspected
• Does NOT cause tooth staining in children when used to treat RMSF

Prevent tick bites

• Check for ticks on people and pets daily
• Wear insect repellant
• Treat pets for ticks

• Doxycycline is the most effective antibiotic for the treatment of suspected rickettsial infections, including Rocky Mountain spotted fever (RMSF).
• Delay in treatment of rickettsial diseases may lead to severe illness or death. Children are five times more likely than adults to die from RMSF.
• Misperceptions about the use of doxycycline for children prevent kids from getting lifesaving treatment.
• Doctors often avoid prescribing doxycycline to young children because of a warning that tooth staining may occur when used in children less than 8 years old.
• In a recent study, experts at the CDC and Indian Health Service (IHS) found that short courses of the antibiotic doxycycline can be used in children without causing tooth staining or weakening of tooth enamel.

Background on doxycycline and older tetracycline antibiotics

Tetracycline antibiotics are broad-spectrum antibiotics in use since the 1940s. Older tetracycline-class antibiotics have been linked to cosmetic staining of permanent teeth when used in children before the age of 8 years. As a result, in 1970 a warning label was attached to all tetracycline-class antibiotics advising against the use in children under the age of 8 years.

In 1967 doxycycline was introduced as a newer tetracycline-class antibiotic. Doxycycline binds less readily to calcium and has not been shown to cause the same tooth staining. Several studies have previously been published showing the lack of staining of permanent teeth when doxycycline was used in children. The warning, currently present on all tetracycline-class antibiotics, including doxycycline, continues to mention the concern regarding dental staining.

Doxycycline and rickettsial diseases

Doxycycline is the most effective treatment of all rickettsial diseases including Rocky Mountain spotted fever, ehrlichiosis and anaplasmosis. It is the antibiotic recommended by the American Academy of Pediatrics (AAP) and CDC for the treatment of suspected rickettsial diseases in patients of all ages. Studies have shown that other antibiotics are less effective and are associated with a higher number of deaths (case fatality rate).

In a 2012 national survey, 80% of clinicians correctly selected doxycycline as the treatment of choice for suspected RMSF in persons 8 years or older, however, only 35% of clinicians correctly chose doxycycline as the treatment of choice for suspected RMSF in children under 8 years. This hesitation may contribute to the increased fatality rate among children. Children under the age of 10 years represent 6% of RMSF cases, but they represent 22% of deaths. The same disproportionate case fatality rate in children has been observed for ehrlichiosis and other serious rickettsial infections.

Case Fatality Rate of Spotted Fever Rickettsiosis by Age Group, 2008-2013 Case fatality rate by age-group for spotted fever rickettsioses (including RMSF) in the United States, 2008-2012.

Case Fatality Rate of Ehrlichia chaffeensis by Age Group, 2008-2013 Case fatality rate by age-group for ehrlichiosis in the United States, 2008-2012.

Rickettsial diseases begin with non-specific symptoms, such as fever, headache, and gastrointestinal illness. A rash may develop around 2-5 days after the start of symptoms. This disease progresses rapidly into severe illness requiring hospitalization, or even death. Rickettsia can cause damage to the blood vessels leading to organ failure, amputation of extremities from lack of blood flow, and neurological deficits (such as hearing loss, paralysis, and encephalopathy). More than 20% of untreated cases of RMSF are fatal, with the average time from the beginning of symptoms to death being only 8 days.

Digital necrosis in hand with untreated Rocky Mountain Spotted Fever

Digital necrosis may occur with untreated RMSF. Median time to death is only 8 days.

Rocky Mountain Spotted Fever rash on foot

Rash can occur with RMSF, but may start later in illness. Never wait for a rash to begin doxycycline.

Doxycycline is most effective when given within the first 5 days of illness. Because there is no rapid test to diagnose rickettsial diseases, clinicians must diagnose and treat based on clinical suspicion alone. It is important that concern about dental staining not cause providers to use other antibiotics, or delay the start of treatment in children.

The newest evidence

In 2013, researchers from the CDC and IHS began looking into the issue of dental staining following doxycycline usage, to better understand if this is an issue. This study was performed to look at whether or not doxycycline, in the dose and duration used to treat suspected RMSF, caused dental staining in children less than 8 years. The study took place in a community which has suffered from high rates of RMSF since 2003, where a large number of people, including children, were treated with doxycycline.

Dentists inspected the permanent teeth of children who had received doxycycline for suspected RMSF prior to their 8th birthday and those who had not. Blinded dentists (without knowing which children had received the drug) looked for tooth staining, evaluated tooth color, and looked for evidence of weakness in the tooth enamel for all children in the study. No differences were found between children who had received doxycycline and those who had not.

This study provides the largest sample size and best evidence to date that short courses of doxycycline (such as those used to treat rickettsial diseases) do not cause dental staining when given to children under the age of 8 years.

The current label allows for the use of doxycycline in pediatric rickettsial patients because other antibiotics are not likely to be effective for treatment. However, clearer language on the drug label may help avoid hesitation in prescribing life-saving doxycycline to children, and reinforce CDC and AAP RMSF treatment recommendations. Despite the current label warning, it is important for healthcare providers to know that doxycycline has not been shown to cause tooth staining in the dose and duration used to treat rickettsial diseases. Early administration of doxycycline in adults and children can prevent severe illness and save lives.

• There is no vaccine to prevent RMSF. Prevent illness by preventing tick bites, preventing ticks on your pets, and preventing ticks in your yard.
• Ticks live in grassy, brushy, or wooded areas, or even on animals, so spending time outside camping, gardening, or hunting will bring you in close contact with ticks. Protect yourself, your family, and your pets. Here’s how:

Tick exposure can occur year-round, but ticks are most active during warmer months (April-September). Know which ticks are most common in your area.

Before You Go Outdoors

• Know where to expect ticks. Ticks live in grassy, brushy, or wooded areas, or even on animals. Spending time outside walking your dog, camping, gardening, or hunting could bring you in close contact with ticks. Many people get ticks in their own yard or neighborhood.
• Treat clothing and gear with products containing 0.5% permethrin. Permethrin can be used to treat boots, clothing and camping gear and remain protective through several washings. Alternatively, you can buy permethrin-treated clothing and gear.
• Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. EPA’s helpful search tool can help you find the product that best suits your needs. Always follow product instructions. Do not use products containing OLE or PMD on children under 3 years old.
• Avoid Contact with Ticks
  • Avoid wooded and brushy areas with high grass and leaf litter.
  • Walk in the center of trails.

After You Come Indoors

Check your clothing for ticks. Ticks may be carried into the house on clothing. Any ticks that are found should be removed. Tumble dry clothes in a dryer on high heat for 10 minutes to kill ticks on dry clothing after you come indoors. If the clothes are damp, additional time may be needed. If the clothes require washing first, hot water is recommended. Cold and medium temperature water will not kill ticks.

Examine gear and pets. Ticks can ride into the home on clothing and pets, then attach to a person later, so carefully examine pets, coats, and daypacks.

Shower soon after being outdoors. Showering within two hours of coming indoors has been shown to reduce your risk of getting Lyme disease and may be effective in reducing the risk of other tickborne diseases. Showering may help wash off unattached ticks and it is a good opportunity to do a tick check.

Check your body for ticks after being outdoors. Conduct a full body check upon return from potentially tick-infested areas, including your own backyard. Use a hand-held or full-length mirror to view all parts of your body. Check these parts of your body and your child’s body for ticks:

• Under the arms
• In and around the ears
• Inside belly button
• Back of the knees
• In and around the hair
• Between the legs
• Around the waist