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Rocky mountain spotted fever contagious: Rocky Mountain Spotted Fever (for Teens)


Rocky Mountain Spotted Fever (for Teens)

What Is Rocky Mountain Spotted Fever?

Rocky Mountain spotted fever (RMSF) is a bacterial infection. People get it from the bite of an infected tick. Most infections happen in the spring and summer, when ticks are active.

Doctors treat RMSF with

antibiotics. With prompt treatment, most people recover in a few days.

What Are the Signs & Symptoms of Rocky Mountain Spotted Fever?

RMSF gets its name from the trademark rash it causes. Small red spots and blotches begin on the wrists and ankles, then spread to the palms and soles, and up the arms and legs toward the trunk. Over time, the red spots might start to look more like bruises or bloody dots or patches under the skin.

Other signs of RMSF include:

  • high fever
  • severe headache
  • chills
  • muscle aches and joint pain
  • nausea and vomiting
  • belly pain
  • tiredness

Symptoms often begin suddenly, usually within 1 week of a tick bite, though sometimes a bit later. Often, the person doesn’t remember being bitten by a tick. The rash most often appears 3–5 days after the fever and headache start, but can take longer.

What Causes Rocky Mountain Spotted Fever?

Bacteria called Rickettsia rickettsia cause RMSF. Ticks spread the bacteria when they bite a person. Infections are most common in the southeastern part of the United States, but can happen in other states.

Is Rocky Mountain Spotted Fever Contagious?

RMSF isn’t contagious, and can’t spread from person to person. The infection spreads through the bite of an infected tick.

How Is Rocky Mountain Spotted Fever Diagnosed?

Doctors usually diagnose RMSF based on:

  • a person’s symptoms
  • whether the person had a recent tick bite or was in an area likely to have ticks

A blood test and skin test can help diagnose RMSF, but getting the results takes time, so treatment often starts before the results are ready.

How Is Rocky Mountain Spotted Fever Treated?

Doctors treat RMSF with antibiotics. Depending on how serious the symptoms are, a person might take these by mouth or get them through an IV (intravenously). Most people recover within a few days.

An infection that isn’t treated right away can cause serious health problems, which can affect the brain, lungs, heart, and kidneys. Someone with these problems may need long-lasting treatment. RMSF that isn’t treated can be life-threatening.

Can Rocky Mountain Spotted Fever Be Prevented?

To help protect yourself from Rocky Mountain spotted fever, follow these outdoor safety tips:

  • Avoid tick-infested areas, like woods and tall grasses, brush, shrubs, and low tree branches.
  • Don’t sit on the ground in wooded areas.
  • Use insect repellent containing 10% to 30% DEET.
  • Dress in closed shoes, long sleeves, and pants when in wooded or grassy areas. Tuck the shirt into pants and the pant legs into socks to keep ticks out.
  • Wear light-colored clothing so ticks are easier to see.
  • Check yourself and any pets for ticks when you come indoors.

Not all ticks carry the RMSF bacteria, but it’s wise to remove any right away. The longer a tick stays attached to the skin, the greater the chance of infection. It usually takes several hours for a tick to spread the bacteria that cause RMSF when it’s attached to the skin.

To remove a tick, use tweezers to grasp it by the head, as close to the skin as possible. Pull steadily until it comes loose. 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.

Check pets’ 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 keep your pet tick-free.

What Else Should I Know?

If you’re recovering from RMSF at home, take the antibiotics as the doctor directed. Rest in bed until the fever and other symptoms are gone.

When Should I Call the Doctor?

Call the doctor if you think a tick bit you or you have:

  • a fever
  • achiness
  • a stiff neck
  • a rash

Rocky Mountain Spotted Fever | Johns Hopkins Medicine

What is Rocky Mountain spotted fever?

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. It was first recognized in the Rocky Mountain states, but may occur throughout the U.S. Most common areas affected are in the southeastern and south central U.S. The disease is spread to humans through a bite from an infected tick. It is not spread from person to person.

What causes Rocky Mountain spotted fever?

RMSF is caused by a bacterium that is spread to people by the bite of an infected tick. In the U. S., the American dog tick, the Rocky Mountain wood tick, and the brown dog tick are the ticks that transmit the RMSF bacteria.

Who is at risk for Rocky Mountain spotted fever?

People living in or visiting areas where ticks are prevalent, particularly the southeastern and south central U.S., are at risk for Rocky Mountain spotted fever.

What are the symptoms of Rocky Mountain spotted fever?

The following are the most common symptoms of RMSF:

  • A non-itchy rash that usually starts on the hands, arms, feet, and legs and occurs 5 to 10 days after the bite. The rash consists of flat, pink spots.
  • Fever
  • Headache
  • Confusion
  • Decreased appetite
  • Chills
  • Sore throat
  • Stomachache
  • Nausea or vomiting
  • Diarrhea
  • Body aches
  • 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 look like other conditions or medical problems. See a healthcare provider for diagnosis.

How is Rocky Mountain spotted fever diagnosed?

Diagnosis is based on symptoms and history of a tick bite. How the rash looks is important. Skin samples and lab tests are usually done to rule out other conditions and confirm the diagnosis.

How is Rocky Mountain spotted fever treated?

Specific treatment for Rocky Mountain spotted fever will be determined by your healthcare provider based on the following:

  • How old you are
  • Your overall health and medical history
  • How sick you are
  • How well you can handle specific medicines, procedures, or therapies
  • How long the condition is expected to last
  • Your opinion or preference

Treatment may include antibiotics (usually doxycycline) until several days after the fever goes away. Efforts to relieve symptom also helps.

What are the complications of Rocky Mountain spotted fever?

RMSF can be cured when treated with antibiotics. However, if untreated, serious complications can occur including:

  • Nerve damage
  • Hearing loss
  • Incontinence
  • Partial paralysis
  • Tissue death (gangrene) of toes or fingers
  • Rarely, death

Can Rocky Mountain spotted fever be prevented?

Once you’ve had RMSF, you can’t get it again. To help prevent RMSF, follow these guidelines.


Ticks can’t bite though clothing, so dress in:

  • Light-colored clothing (so you can spot ticks on clothing easier)
  • Long-sleeved shirts tucked into pants
  • Socks and closed-toe shoes
  • Long pants with legs tucked into socks

Checking for ticks

It’s important to check often for ticks, especially on these parts of the body:

  • Around the joints: 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 anywhere that clothing presses tightly 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 hair to check for ticks.

Insect repellent

Be sure to use any insect repellents safely.

  • Products that contain DEET are tick repellents, but may not kill the tick and are not 100% effective. For children, use a children’s insect repellent (20% to 30% DEET). Check with your child’s healthcare provider 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. Don’t use permethrin on skin.

Other measures

The following may also be helpful:

  • 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 4 to 6 hours for ticks to attach firmly to skin. Showering may help remove any loose ticks.
  • Check pets for ticks and treat as needed.

When should I call my healthcare provider?

If your symptoms get worse or you have new symptoms, let your healthcare provider know.

Key points about Rocky Mountain spotted fever

  • RMSF is caused by a bacterium that is spread to people by the bite of an infected tick.
  • Symptoms include a rash, fever, headache, decreased appetite, chills, sore throat, confusion, stomach ache, nausea or vomiting, diarrhea, body aches, and sensitivity to light.
  • Treatment includes antibiotics and symptom relief.
  • If untreated, serious complications, including nerve damage, hearing loss, incontinence, partial paralysis, and gangrene of toes or fingers, can occur.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
  • Ask if your condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if you do not take the medicine or have the test or procedure.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.

Mississippi State Department of Health

Rocky Mountain spotted fever (RMSF) is a potentially fatal infectious disease transmitted to
humans by the bite of an infected tick. The disease occurs throughout the
United States during months when ground temperatures reach 40 degrees
Fahrenheit or more and ticks are active.

In spite of the disease’s name, few cases have been reported from the Rocky Mountain region of the United States. Around 100 probable cases of RMSF are identified each year in Mississippi.

Who can get Rocky Mountain spotted fever?

Rocky Mountain spotted fever affects both children and adults bitten by disease-carrying ticks.
The risk of RMSF is highest among those exposed to tick-infested habitats or pets.

How is Rocky Mountain spotted fever spread?

Rocky Mountain spotted fever is spread by the bite of an infected tick (the common
American dog tick or the lone-star tick) or by contamination of the skin with
tick blood or feces. It is not a contagious disease: person-to-person transmission does not occur.

What are the symptoms of Rocky Mountain spotted fever?

Rocky Mountain spotted fever is characterized by the sudden onset of moderate
to high fever lasting up to three weeks, severe headache,
fatigue, deep muscle pain, chills and sometimes a rash. When present, 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 the rest of the body. Rocky Mountain spotted fever can be a severe or even fatal illness if not treated in the first few days of symptoms.

Sole of the foot with advanced RMSF rash

How soon do symptoms appear?

Symptoms usually appear between 3 and 14 days after the bite of an
infected tick. Any person experiencing illness with a fever following a tick
bite should consult his or her physician and advise the physician of the tick

How serious is Rocky Mountain spotted fever?

Early treatment with antibiotics lowers the risk of overall mortality to
between 3 and 5 percent. Untreated cases have a from 13 percent to
25 percent rate of mortality. Death primarily occurs when the diagnosis is not made until the second week of illness.

How can Rocky Mountain spotted fever be prevented?

Persons spending time outdoors in areas where ticks are commonly found
– wooded areas, tall grass and brush – should take precautions
against all tick-borne diseases:

  • Check your clothing often for ticks climbing toward open skin. Wear white
    or light-colored long-sleeved shirts and long pants so the tiny ticks are
    easier to see. Tuck long pants into your socks and boots. Wear a head covering
    or hat for added protection.
  • Apply insect repellent containing DEET (30 percent or less) to exposed skin (except the face). Repellents containing permethrin can be applied to outer clothing
    while in locations where ticks may be common. Follow label directions; do not misuse or overuse repellents. Always supervise children in the use of repellents.
  • Walk in the center of trails so weeds do not brush against you.
  • Check yourself, children and other family members every two to three hours for ticks. Most ticks are slow to attach, and rarely transmit disease until they have been attached for several hours.
  • If you let your pets outdoors, check them often for ticks. Ticks can enter the home on pets and fall off in search of a host.
  • Keep your grass mowed and keep weeds cut to keep the area unattractive to ticks.

Information courtesy of the Illinois Department of Public Health

The best way to
remove a tick is to grasp it with fine-point tweezers as close to the skin as
possible and gently but firmly pull it straight out. If tweezers are not available, grasp the tick with your fingers, using a piece of cloth or
other material as a barrier between your fingers and the tick.

  • Do not try to burn the tick with a match or cover it with petroleum jelly or nail polish.
  • Do not use bare hands.
  • Do not twist or jerk the tick.

Remove any tick promptly. The mouthparts of a tick may remain embedded in the skin and lead to infection at the bite site if not removed properly.

You may want to put the tick in a jar of rubbing alcohol labeled with the date and
location of the bite in case you seek medical attention and your physician
wishes to have the tick identified.

Wash the bite area and your hands thoroughly with soap and water,
and apply an antiseptic to the bite site.

More Information

Rocky Mountain Spotted Fever Fact Sheet

Last Reviewed: July 2017

What is Rocky Mountain Spotted Fever?

Rocky Mountain spotted fever (RMSF) is a disease caused by the bite of a tick infected with the bacterium Rickettsia rickettsii. In New York, the American dog tick (Dermacentar variablis) is the most common tick that spreads the disease. Fewer than 50 cases are reported annually in New York State. RMSF is a serious illness that can be fatal in the first 8 days of symptoms if not treated correctly, even in previously healthy people. The course of the disease varies greatly. Patients who are treated early may recover quickly on outpatient medication, while those who experience a more severe course may require intravenous antibiotics, prolonged hospitalization or intensive care.

Who gets RMSF?

People of any age can get RMSF. In the eastern United States, children are infected most frequently, while in the western United States, adult males are more likely to become infected. Disease occurrence is directly related to exposure to tick-infested habitats or to infested pets.

How is RMSF spread?

RMSF is spread by the bite of an infected tick. In New York, the American dog tick (Dermacentar variablis) is the most common carrier. Person-to-person spread of RMSF does not occur.

What are the signs and symptoms of RMSF and when do they appear?

RMSF frequently begins with a sudden onset of moderate to high fever (which can last for 2 or 3 weeks), headache, abdominal pain, vomiting, and muscle pain. A rash may also develop, but is often absent in the first few days, and in some patients never develops. The rash is often present on the palms of the hands and soles of the feet and rapidly spread to the trunk or the rest of the body. Symptoms usually appear 2-14 days after the bite of an infected tick occurs.

How is RMSF diagnosed?

Symptoms and possible tick bite exposure may cause a health care provider to suspect RMSF. Laboratory testing can later confirm the diagnosis.

What is the treatment for RMSF?

A specific antibiotic called doxycycline is the first line of treatment for adults and children of all ages and should be started immediately when RMSF is suspected. It is most effective when this treatment is started within 5 days of when symptoms start. Since starting treatment early is crucial for survival of this disease, when RMSF is suspected, treatment should never be delayed while waiting for laboratory test results.

Does past infection with RMSF make a person immune?

One infection probably provides permanent immunity.

What can be done to prevent RMSF?

Generally, ticks cannot jump or fly onto a person. They wait in vegetation and cling to animals and humans when they brush by. Domestic animals can carry ticks into areas where you live such as your house or garage, so brush off animals and look for ticks before they enter these areas. The best prevention is through awareness. Check after every two to three hours of outdoor activity for ticks on clothing or skin. Brush off any ticks on clothing or skin before skin attachment occurs. A careful check of all body surfaces for attached ticks should be done at the end of the day. If removal of attached ticks occurs within 36 hours, the risk of tick-borne infection is minimal. For proper tick removal, please watch the video at
Tick removal.

Insect repellents can be effective at reducing bites from ticks that can spread disease. If you decide to use a repellent, use only what and how much you need for your situation. More information on repellents can be found at Environmental Protection Agency – insect-repellents.

In addition:

  • Be sure to follow label directions.
  • Try to reduce the use of repellents by dressing in long sleeves and pants tucked into socks or boots.
  • Children should only handle repellents with adult supervision. Adults should apply repellents to their own hands first and then gently spread on the child’s exposed skin. Avoid applying directly to children’s hands. After returning indoors, wash your child’s treated skin and clothing with soap and water or give the child a bath.
  • Do not apply near eyes, nose or mouth and use sparingly around ears.
  • After returning indoors, wash treated skin with soap and water.
  • Dogs are susceptible to RMSF and owners should use tick collars, sprays, shampoos, or medications regularly to protect their pets and families from ticks.

How should a tick be removed?

Grasp the mouthparts with tweezers as close as possible to the attachment (skin) site. Be careful not to squeeze, crush or puncture the body of the tick, which may contain infectious fluids. Pull firmly and steadily upward to remove the tick. After removing the tick, thoroughly disinfect the bite site and wash hands. The NYSDOH has created a video on proper tick removal (Proper Tick removal) and a printable card with steps on how to remove ticks (How to Remove a Tick Card). See or call a doctor if there are concerns about incomplete tick removal. Do not attempt to remove ticks by using petroleum jelly, lit cigarettes or other home remedies because these may actually increase the chance of contracting a tick-borne disease.

Rocky Mountain Spotted Fever | Lyme Disease


Rocky Mountain spotted fever (RMSF) is one of about a dozen spotted fever illnesses found in the Americas, Europe, Asia and Australia. All are caused by bacteria belonging to the genus Rickettsia, a group of pleomorphic (shape-changing), non-motile microbes that replicate only inside of eukaryotic host cells.

Incidence of Rocky Mountain spotted fever cases per million population, 1993-1996, based on national surveillance figures. Reprinted from Treadwell TA, Holman RC, Clarke MJ, et al. Rocky Mountain spotted fever in the United States, 1993-1996. Am J Trop Med Hyg 2000;63:21-26.

Although first described in the Snake River Valley region of Idaho in 1896 (hence its name), Rocky Mountain spotted fever is actually more common in the south Atlantic and south central parts of the United States. It is caused by Rickettsia rickettsii and is transmitted to humans in the United States by two primary tick vectors, the American dog tick (Dermacentor variabilis) and the Rocky Mountain wood tick (Dermacentor andersoni). The brown dog tick, Rhipicephalus sanguineus, has been implicated in some cases of RMSF as well.

Prior to the antibiotic era, Rocky Mountain spotted fever had a mortality rate of up to 30%. Even today, it remains the most common fatal tick-borne disease in the United States; about three to five percent of patients who acquire the infection will die from it. Most of these fatalities occur in the very young and very old and are due to delayed diagnosis and treatment.

The Centers for Disease Control typically receives somewhere between 300-1200 case reports of RMSF each year, although the number has been increasing in recent years. As with many tick-borne infections, there is a seasonal peak in the late spring and summer months, with May, June, and July accounting for the most cases. More than 90% of cases are reported from April through September. The disease strikes children disproportionately — peak incidence is in the five to nine age group, and more than half of all reported cases involve children under 15 years old.

Signs and Symptoms

The usual incubation time between tick bite and symptom onset is five to ten days. Only about half of patients recall a preceding tick bite. Initial symptoms of Rocky Mountain spotted fever are usually non-specific, consisting of fever, severe headache, myalgias, nausea, and loss of appetite. Many patients will present to physicians before the hallmark rash develops, which complicates diagnosis and increases the disease’s potential deadliness.

Rash onset is subtle and usually develops within two to five days after symptoms begin. The rickettsiae spread through the lymphatic system, eventually parasitizing and multiplying within endothelial cells. As the host cells die, blood leaks into adjacent tissues, causing both rash and damage to internal organs. Typically, pale spots first appear on the patient’s extremities (hands, feet, forearms, and ankles) and eventually spread inward, toward the trunk.

Classic rash of Rocky Mountain spotted fever. Photo courtesy of the Centers for Disease Control and Prevention.

The “classic” RMSF rash, consisting of small, bright red petechial (spotted) lesions, does not usually appear until almost a week after symptom onset. Estimates vary as to its prevalence, with most sources stating that it presents eventually in about half of all RMSF patients. Close to 5% of patients will develop gangrene or skin necrosis, sometimes requiring amputation of the affected extremities.

Around 10-15% of RMSF patients will not develop rash at any stage.

Rocky Mountain spotted fever is multisystemic and potentially severe. Central nervous system manifestations include lethargy and confusion (about 25% of all cases), ataxia (18%), coma (9-10%), and seizures (8%). Other neurologic manifestations include meningitis, cranial neuropathies, deafness, paralysis, spasticity, vertigo, aphasia, and photophobia. Ophthalmologic complications can also occur. In addition, RMSF affects the respiratory system, the gastrointestinal system, and the renal system. Pulmonary involvement includes edema, pneumonia, and respiratory distress syndrome. Microcirculatory vasculitis can lead to myocarditis. Close to 10% of patients develop jaundice during the course of their illness; a similar percentage will produce stools positive for occult blood. Hospitalization is frequently required in advanced cases of RMSF.

African-American males are at particular risk for serious complications of Rocky Mountain spotted fever, as they are genetically more likely to be deficient in glucose-6-phosphate dehydrogenase (G6PD), an enzyme associated with the maintenance of membrane integrity in red blood cells.


While a number of laboratory tests are available for Rocky Mountain spotted fever, none are both rapid and sensitive enough to provide useful diagnostic assistance to the examining physician. As prompt treatment of RMSF is critical to a positive outcome, diagnosis should be made on clinical grounds — i.e., history, epidemiology, and clinical exam. This can be challenging, as many patients will not recall the tick bite.

Conventional blood tests can produce results that hint at RMSF. Among the typical findings are hypoanotremia (low sodium), thrombocytopenia, white blood cell abnormalities, and/or elevated liver enzymes.

Serological assays are used mostly to confirm the diagnosis after treatment has been initiated. Indirect immunofluorescence assays (IFA) of both IgM and IgG antibodies are most commonly employed, but enzyme linked immunosorbent assays (ELISA) and dot immunoassays are also available. Complement fixation is less sensitive, and less frequently used. Immunostaining of biopsied skin rashes can also be performed and is very rapid; results are available in a few hours. However, the test is only 70% sensitive, so a negative result does not exclude the diagnosis.

Polymerase chain reaction (PCR) assays for R. rickettsii DNA are considered perhaps the most timely and specific test for RMSF overall, but are still not widely available.


Rocky Mountain Spotted Fever | NIH: National Institute of Allergy and Infectious Diseases

A male cayenne tick, Amblyomma cajennense, a tick species which is a North, Central, and South American carrier of Rickettsia rickettsii bacteria, which cause Rocky Mountain spotted fever.

A male cayenne tick, Amblyomma cajennense, a tick species which is a North, Central, and South American carrier of Rickettsia rickettsii bacteria, which cause Rocky Mountain spotted fever.


Rocky Mountain spotted fever is a tickborne disease first recognized in 1896 in the Snake River Valley of Idaho. It was originally called “black measles” because of the look of its rash in the late stages of the illness, when the skin turns black. It was a dreaded, often fatal disease, affecting hundreds of people in Idaho. By the early 1900s, the disease could be found in Washington, Montana, California, Arizona, and New Mexico.

Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID?

Tickborne diseases are becoming a serious problem in this country as people increasingly build homes in formerly uninhabited wilderness areas where ticks and their animal hosts live. Tickborne diseases can be caused by viruses, bacteria, or parasites. Most people become infected through tick bites during the spring and summer months.

How Is NIAID Addressing This Critical Topic?

Because of the work started by Dr. Ricketts in the early 1900s, NIAID Rocky Mountain Laboratories (RML) remains a thriving center for infectious disease research on tickborne diseases, such as Lyme disease and relapsing fever. RML also continues to do research on rickettsial diseases.

Information for Researchers

NIAID offers resources, information about funding, and ways to connect to other scientists researching tickborne diseases including Rocky Mountain spotted fever.

Read more about research on tickborne diseases

Rocky Mountain Spotted Fever (RMSF) in Dogs

Rocky Mountain spotted fever (RMSF) is a zoonosis which means it can be spread between animals and humans. Many such zoonotic diseases are transmitted through insects like mosquitoes and ticks. RMSF is caused by a very small type of bacteria called Rickettsia rickettsii which is injected into people and dogs by feeding ticks. However, direct transmission of organisms from dogs to people is not known to occur. 

Once established inside the animal, the rickettsial organisms cause damage and inflammation in tiny blood vessels resulting in the ‘spots’ referred to in the common name for the disease. These little areas of hemorrhage are often visible on the skin but they also occur in other internal organs like the heart, brain and kidney and can result in serious, potentially life-threatening/fatal illness.

The incubation period from infection to onset of clinical signs can vary from just a few days to two weeks; often times the connection may not be made between the presence of a tick and the later development of illness.

Symptoms of Rocky Mountain spotted fever
Symptoms can be very non-specific in dogs and in people:

  • Fever
  • Nausea
  • Vomiting
  • Lack of appetite
  • Muscle pain

Diagnosing Rocky Mountain spotted fever
True diagnostic testing is based on demonstrating RMSF DNA in the patient’s blood by polymerase chain reaction (PCR) testing. Serology, which tests for a rising immune response over time, can also be performed. That means the results are not available until well into the illness. Unfortunately, Not every patient develops a rash, and when they do it is often a few days after they become clinically ill.

Treatment of Rocky Mountain spotted fever
Since treatment with the antibiotic doxycycline is most effective when started before the fifth day of symptoms, any delay in diagnosis and treatment can be profoundly significant in terms of outcome and prognosis. As a result, treatment is typically instituted based on clinical symptoms, location, and risk of exposure alone (with or without known tick bites).

What regions are at risk for Rocky Mountain spotted fever?
First and foremost, do not let the name of the disease fool you into a false sense of security based on where you live. Even though the disease was first recognized in the Rocky Mountains, only a small percentage of all cases are now found there. The CDC says, “RMSF cases have been reported throughout most of the contiguous United States, with five states (North Carolina, Oklahoma, Arkansas, Tennessee, and Missouri) accounting for over 60% of RMSF cases.” Also, while according to the CDC “the proportion of RMSF cases resulting in death has declined to a low of less than 0.5, the incidence of the disease itself has increased during the last decade.”

Prevention of Rocky Mountain spotted fever
Tick control and prevention of transmission are your best defense for both you and your pet. The Companion Animal Parasite Council recommends that, “all dogs be maintained year round on tick control products.” (See your veterinarian about what to use for your particular pet.) In addition tick control efforts can be aided by removing tick habitats around the home:

  • Trim brush
  • Clip grass
  • Remove leaf litter
  • Exclude wildlife by installing fencing and removing debris
  • Limit contact with infested areas by preventing roaming in dogs

Of course, you should always carefully check your pets, yourselves, your clothing, and your belongings for ticks.

The timely removal of ticks is absolutely essential in preventing RMSF because, unlike other tick borne illness, e.g., Lyme or ehrlichia where the ticks need to be feeding for approximately 24-48 hours before transmitting infectious organisms, with RMSF “transmission generally occurs 5 to 20 hours after tick attachment,” says capcvet.com. Tick removal and handling must be done very carefully because the rickettsial bacteria can also be transmitted through fluids, tissues, blood, or feces through cuts or sores on your skin.

In conclusion, RMSF is a serious, sometimes fatal illness for both dogs and people that occurs to some degree in most areas of the United States. Because it can be difficult to diagnose early enough for effective treatment, the best defense is to guard against exposure in the first place.

[Editor’s Note: Annual testing is important to protect your dog from ticks. Learn more here.]

If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.


Beware the Bug

Ticks 101

By Dr. Ruth MacPete

Anaplasma is spread by ticks. As the weather gets warmer and dogs spend more time outside, they’re more likely to be exposed to these creepy parasites and all of the diseases they carry. Read more> Or learn more about dogs and parasites >



90,000 Rocky Mountain Spotted Fever – Symptoms, Diagnosis and Treatment

Rocky Mountain Spotted Fever is a notifiable disease. Can be fatal if left untreated early.

For the treatment of patients of any age, the drug of choice is doxycycline, which almost always gives positive treatment results, especially if it is used during the first 5 days of illness. Since the risk of death increases if appropriate treatment is not started in a timely manner (within the first 5 days), doxycycline should be prescribed if the disease is suspected, until the results of a confirmatory diagnostic test are obtained.

Signs and symptoms are sometimes difficult to distinguish from those seen in common viral diseases, leading to delayed diagnosis. The diagnosis should be suspected of any person with an appropriate clinical picture of the disease and recent exposure to the open area.

There is no characteristic scab or crust at the site of the tick bite, unlike other infections from the group of hemorrhagic spotted fevers caused by rickettsia and carried by ticks.In almost half of cases, a history of tick bites may be absent.

Rocky Mountain spotted fever (RSPF) develops as a result of infection with the tick-borne intracellular gram-negative bacterium Rickettsia rickettsii. [1] Biggs HM, Behravesh CB, Bradley KK, et al. Diagnosis and management of tickborne rickettsial diseases: Rocky Mountain spotted fever and other spotted fever group rickettsioses, ehrlichioses, and anaplasmosis – United States. MMWR Recomm Rep.2016; 65: 1-44.

Rickettsia rickettsii is one of the rickettsia of the spotted fever group (HPF) and is closely related to other members of the group in terms of genetic and antigenic characteristics. This rickettsiosis is the most common HPF infection in North America and the most common lethal tick-borne infection in the United States.[2] Drexler NA, Dahlgren FS, Heitman KN, et al. National surveillance of spotted fever group rickettsioses in the United States, 2008-2012. Am J Trop Med Hyg. 2016; 94: 26-34.
[3] Openshaw JJ, Swerdlow DL, Krebs JW, et al. Rocky mountain spotted fever in the United States, 2000-2007: interpreting contemporary increases in incidence. Am J Trop Med Hyg. 2010; 83: 174-182.

http: // www.ncbi.nlm.nih.gov/pubmed/20595498?tool=bestpractice.com
For more information on other rickettsial infections, see our separate topic, rickettsial diseases.

Rocky Mountain spotted fever – causes, symptoms, diagnosis and treatment

Rocky Mountain spotted fever is an acute natural focal zoonosis with a predominantly transmissible mechanism of transmission caused by rickettsia. The clinical picture is characterized by the presence of fever, general intoxication syndrome, profuse maculopapular rash with a hemorrhagic component, signs of damage to the nervous and cardiovascular systems.Diagnosis is based on the detection of serological markers in the patient’s serum. The PCR method is used. Treatment is carried out with antibacterial drugs from the tetracyclines group. In parallel, symptomatic therapy is prescribed.


The disease was first reported in the highlands of the United States in 1899. Spotted fever is known by various names: mountain fever, Brazilian typhus, tick-borne rickettsiosis of America.This nosology is common in the USA, Canada, Central and South America. Seasonality is characteristic. The peak incidence is recorded in the spring-summer period, which is associated with the high activity of tick vectors. The susceptibility is general, but more often men from 40-65 years old and children under 10 years old living in rural areas are ill. This trend can be explained by the choice of profession (foresters, hunters) and active recreation, respectively.

Rocky Mountain spotted fever


The causative agent of spotted fever is the gram-negative bacillus Rickettsia rickettsii.Differs in pronounced polymorphism. In cells, it is found both in the cytoplasm and in the nucleus. The microorganism is sensitive to heat, quickly inactivated at temperatures above 50 ° C and under the influence of disinfectants. It is resistant to freezing and remains dry for a long time. The reservoir and source of infection are wild rodents, cattle, dogs. In addition, certain species of ixodid ticks are considered vectors and persistent reservoirs. Man is a casual master. Infection occurs when an insect bites or when a tick is crushed and rubbed in the area of ​​scratching.In the vector, rickettsiae persist throughout life, are transmitted transovarially.


The pathogenesis of Rocky Mountain spotted fever is associated with the affinity of rickettsia to endothelial cells. The primary focus after a tick bite does not form. The parasite enters the regional lymph nodes, and then into the systemic circulation. The pathogen is fixed on endothelial cells, penetrates into them and promotes the development of necrosis. Vessels of small and medium caliber of different localization are mainly affected.As a result, parietal thrombi are formed, the production of biologically active substances increases with an increase in the degree of intoxication, antibodies to endothelial cells begin to be produced.

Around the affected vessels, infiltrates are formed, consisting of lymphocytes, macrophages, plasma cells and microscopically resembling granulomas. Destructive or destructive-proliferative vasculitis develops. When the muscular wall of the vessels is involved in the pathological process, panvasculitis is observed.The most common damage to the vessels of the kidneys, adrenal glands, skin, heart and brain. The characteristic rash is the result of pathomorphological changes in the vessels of the skin. When the lumen is obstructed by a thrombus, necrosis of the corresponding anatomical regions is formed.


The course of rickettsiosis can be varied and accompanied by various symptoms. The main triad of the disease includes a pronounced febrile reaction, headache and a characteristic rash that appears in a short period of time.In clinical practice, moderate and severe forms of the disease prevail. American scientists have proposed the following classification of Rocky Mountain spotted fever:

  • Outpatient form. Subfebrile temperature is observed. A slight intoxication with a moderate feeling of malaise, weakness is revealed. The rash may be atypical, with an uncharacteristic localization, or absent altogether.
  • Abortive form . There is a sharp rise in temperature to high numbers.The febrile period is about 7 days. A specific rash also persists for about a week, then disappears, giving way to prolonged pigmentation and peeling.
  • Typical shape. A typical clinical picture is formed with severe fever lasting about 3 weeks, headaches and muscle pains. Hemorrhagic rash is first detected on the limbs, then spreads to the center of the body.
  • Lightning mold .It is characterized by an extremely severe course with severe intoxication and decompensation of the state. The patient from the first days may fall into a coma. In most cases, it is fatal in 4-5 days.

Fever symptoms

The incubation period can be up to 2 weeks, with an average of 7 days. Sometimes the height of the disease is preceded by a short prodromal period, manifested by malaise, headaches, and loss of appetite. Usually, the disease begins acutely with a sharp rise in body temperature to 39-41 ° C, pronounced arthralgias, myalgias and headaches.Possible abdominal pain mimicking acute appendicitis (more often in children). Some patients have edema of the dorsal side of the palms. Often there is nausea, vomiting, nosebleeds. In some cases, periorbital edema and conjunctival vascular injection are formed. When examining the oral cavity, hemorrhagic rashes on the mucous membranes are found. Gradually, the fever becomes remitting in nature with daily temperature fluctuations up to 1.5 ° C. The febrile period lasts 2-3 weeks.

On the 3-5th day of the disease, a maculopapular rash appears on the skin of patients. Primary localization is typical of the ankle joints, wrists and elbows with subsequent spread throughout the body. Items are prone to merging. In severe cases, exanthema is found on the palms and soles. From 8-10 days of the course of the pathology, the rash becomes hemorrhagic, which in severe forms leads to the formation of necrosis in the area of ​​the tips of the nose and ears, soft palate and genitals.The rash begins to disappear after the body temperature drops. In place of the elements, pigmentation and pityriasis peeling remain for a long time.

Somatic symptoms most often include signs of damage to the cardiovascular system and the central nervous system. Possible hypotension, bradycardia, deafness of heart sounds. Tachycardia corresponds to an extremely severe course of the disease. Collapses are not uncommon. Involvement of the nervous system is accompanied by delirium, convulsions, paresis and paraplegia, paralysis of the cranial nerves, the appearance of pathological reflexes, impaired consciousness of varying severity up to the development of coma.Hepatolienal syndrome is rarely detected. More than half of patients develop constipation. There are no specific symptoms of damage to the respiratory and urinary systems.


The most common complications of Rocky Mountain spotted fever are pneumonia and phlebitis. Perhaps the development of glomerulonephritis, myocarditis with the onset of acute heart failure, neuritis, iritis and obliterating endarteritis, the formation of gangrene of characteristic localization.With the defeat of the cranial nerves, the appearance of the corresponding symptoms is noted (usually – dysfunctions of the organs of hearing and vision). Sometimes convulsions, meningismus, Guillain-Barré syndrome are detected. Coma is considered the most formidable complication. On the part of the gastrointestinal tract, bleeding of various localization, perforation, hepatomegaly with jaundice can be observed. Cases of rapid decompensation have been reported in alcoholics and in black men with glucose-6-phosphate dehydrogenase deficiency.


During a physical examination, the infectious disease doctor detects a specific rash on the skin, sometimes the presence of hemorrhagic elements on the oral mucosa. Rarely, there is a primary affect with regional lymphadenitis. With signs of CNS damage, a neurologist is consulted, who identifies pathological reflexes and symptoms of cranial nerve damage. The following laboratory methods are used to diagnose Rocky Mountain spotted fever:

  • General laboratory tests. In the general analysis of blood, anemia, thrombocytopenia are determined. According to the results of a biochemical blood test, electrolyte imbalance in the form of hyponatremia is possible, sometimes an increase in the levels of bilirubin, hepatic transaminases, urea and creatinine. In the cerebrospinal fluid, leukocytosis with elevated or normal glucose levels is noted.
  • Identification of infectious markers. Use the determination of the increase in the titer of specific antibodies in the patient’s blood by ELISA, RIF.An IgM titer> 1:64, IgG> 1: 128 is considered diagnostically significant. Bioassay is used to isolate the pathogen. PCR diagnostics developed. The complement binding reaction is highly specific.

Differential diagnosis is carried out with other spotted fevers, endemic and epidemic typhus, as well as leptospirosis, yersiniosis and secondary syphilis. It is necessary to exclude monocytic ehrlichiosis and human granulocytic anaplasmosis. Differentiation with hemorrhagic vasculitis and infectious erythema is sometimes required.In children, it is important to distinguish rickettsiosis from group A streptococcus pharyngitis, with the onset of a rash after an acute period.

Treatment of spotted fever

Treatment should be carried out in a hospital under the supervision of an infectious disease specialist with the possibility of transferring to the intensive care unit. Antibacterial agents of the tetracycline series are prescribed, it is possible to use tetracycline and doxycycline. Chloramphenicol is the drug of choice for the treatment of pregnant women. In parallel, symptomatic therapy is carried out (antipyretic, intravenous infusion).Particular attention is paid to the control of electrolyte and water balance. With the development of complications, the treatment plan is adjusted in accordance with the nature of the pathological changes.

Forecast and prevention

The forecast is doubtful. Mortality, according to various sources, ranges from 5 to 80%. Early detection of the pathological condition and the timely administration of antibacterial drugs contribute to a favorable outcome of the disease. Long-term recovery, especially when various body systems are damaged, may be accompanied by the formation of persistent disorders.Specific prophylaxis is not carried out. Non-specific interventions include rodent and tick extermination, wearing special protective clothing, using repellents and personal protective equipment. The correct extraction of the tick and the early initiation of antimicrobial treatment when the first symptoms of the disease appear.

90,000 Rocky Mountain Spotted Fever in Dogs and Cats (RMSF) »Pet AZ

General information

Metazoonosis, which affects both vertebrate and invertebrate hosts, is caused by Rickettsia rickettsii and is a seasonal disease of dogs and humans in America.Rocky Mountain spotted fever in nature is supported by ixodid ticks through transmission from various bodies of water, rodents.


Rocky Mountain Spotted Fever was first described among Native Americans, soldiers, and settlers in the Bitterroot River Valley, Snake Montana, Idaho in the late 1890s. In 1896, Rocky Mountain spotted fever was called “black measles” because it has a high mortality rate.


The gateway of infection for Friday Rocky Mountain Fever in dogs and cats is the skin at the site of the tick bite, with no primary affect at the site of the bite.Rickettsiae through the lymphatic tract enter the bloodstream, parasitize not only in the vascular endothelium, but also in the mesothelium, in muscle fibers. The most pronounced changes in blood vessels in the myocardium, brain, adrenal glands, lungs, skin. Affected vascular endothelial cells are necrotic, parietal thrombi with cellular infiltration around them are formed at the site of injury. With a severe course of the disease, there are extensive ischemic foci in various organs and tissues, and thrombohemorrhagic syndrome develops.


Clinical presentation of Friday Rocky Mountain Fever in dogs and cats:

  • high temperature (39.2-40.5)
  • soreness of the abdomen
  • vomiting
  • brought in
  • anorexia
  • shortness of breath
  • cough
  • Vestibular deficiency (dizziness, tilted head, or nystagmus)
  • petechiae, bruises, hemorrhages (on the mucous membranes of the oral cavity, eyes, genitals)
  • muscle and joint pain
  • edema of limbs, ears, lips, foreskin, scrotum
  • limb necrosis

Treatment and prevention

Antibiotic therapy (tetracycline, doxycycline, chloramphenicol) for 2-3 weeks, as well as symptom therapy, are used to treat Rocky Mountain spotted fever in dogs and cats.The best way to prevent Rocky Mountain spotted fever in dogs and cats is by fighting ticks and not visiting disadvantaged regions.

  1. Wikipedia | Information of Rocky Mountain spotted fever
  2. Apperson, C.S., B. Engber, W.L. Nicholson, D.G. Mead, J. Engel, M.J. Yabsley, K. Dail, J. Johnson and D.W. Watson. 2008. Tick-Borne Diseases in North Carolina: Is “Rickettsia amblyommii” a Possible Cause of Rickettsiosis Reported as Rocky Mountain Spotted Fever ?.Vector-Bone and Zoonotic Diseases. 8: 1-10.
  3. Demma, L.J., M.S. Traeger, W.L. Nicholson, C.D. Paddock, D.M. Blau, M.E. Eremeeva, G.A. Dasch, M.L. Levin, J. Singleton, S.R. Zaki, J.E. Cheek, D.L. Swerdlow, and J.H. McQuiston. 2005. Rocky Mountain Spotted Fever from an Unexpected Tick Vector in Arizona. N. ENGL. J. Med. 353 (6): 587-594.
  4. Masters EJ, Olson GS, Weiner SJ, Paddock CD (2003). “Rocky Mountain spotted fever: a clinician’s dilemma”. Arch. Intern. Med.163 (7): 769-74. doi: 10.1001 / archinte.163.7.769. PMID 12695267
  5. Paddock, C.D., O. Brenner, C. Vaid, D.B. Boyd, J.M. Berg, R.J. Joseph, S.R. Zaki AND J.E. Childs. 2002. CONCURRENT ROCKY MOUNTAIN SPOTTED FEVER IN A DOG AND ITS OWNER. Am. J. Trop. Med. Hyg. 66 (2): 197-199.
  6. Pedro-Pons, Agustín (1968). Patología y Clínica Médicas. 6 (3rd ed.). Barcelona: Salvat. p. 345. ISBN 84-345-1106-1.
  7. Torres, F.D. 2007. Rocky Mountain spotted fever. Lancet Infect Dis.7: 724-732.

90,000 Publications in the media

Rocky Mountain spotted fever – acute transmissible rickettsial infection; characterized by polymorphic fever, often papular-hemorrhagic rash throughout the body, enanthema of the mucous membranes and various complications, especially skin necrosis in the groin area.

Etiology. The causative agent is Rickettsia rickettsii.
Epidemiology • Reported disease in USA, Canada, Mexico, Colombia and Brazil • Reservoir – ticks and wildlife • Carriers – ticks Dermacentor andersoni, Dermacentor variabilis (dog tick), Dermacentor occidentalis; in Central and South America – Amblyomma americanum, Amblyomma cajennense, Amblyomma maculatum and the dog tick Rhinocephalus sanguineus • Men get sick twice as often • The peak incidence is summer • The risk of developing the disease after a tick bite is 20%.

Clinical picture .The duration of the incubation period is 2-14 days • The onset of the disease is gradual or acute, with headaches and muscle pains, photophobia, nausea, vomiting • Fever lasts 3-4 weeks, body temperature reaches 39 ° C and above • On the 2-4th day disease appears maculopapular or petechial rash, first on the extremities, then spreads throughout the body, including the scalp, the mucous membrane of the mouth and eyelids • Possible development of delusional states, stupor or coma • Characterized by skin hyperesthesia, neuritis, bradycardia, arterial hypotension, enlarged liver and spleen, lymphadenopathy, joint pain.

Research methods differential diagnosis – see Trench fever.
Treatment • see Trench fever • Drug therapy is prescribed as early as possible, without waiting for a serological confirmation of the diagnosis (in case of untimely and inadequate treatment, 3-10% of patients die) • The average duration of treatment is 7-10 days.

Course and prognosis • With timely treatment, the prognosis is favorable with resolution of symptoms within a few days and no complications • In untreated cases, mortality reaches 35%; the South American variant of the disease is especially malignant.

Complications • Pneumonia • Hemorrhages of various localization • Phlebitis • Transient encephalopathy • Seizures • ARF • Hepatitis • Cardiovascular failure • Respiratory failure • Necrosis of the skin of the groin.

Prophylaxis • When visiting endemic areas, wear tight clothing with tightening cuffs and treat exposed parts of the body and clothing with repellents. After returning, it is necessary to carefully examine the whole body, especially the legs, groin and genitals, lower back. • If ticks are found, they are carefully removed with gloves, using tools.Before the procedure, it is better to drop a drop of oil, alcohol, gasoline or kerosene on the stuck tick. After removing it, it is necessary to treat the wound with an antiseptic and wash your hands thoroughly.

Synonyms • American tick-borne rickettsiosis • Brazilian typhus • Typhus, Sao Paulo • Blue disease.

ICD-10 • A77.0 Spotted fever due to Rickettsia rickettsii

90,000 Rocky Mountain spotted fever: symptoms, causative agent

Rocky Mountain Spotted Fever.


Rocky Mountain spotted fever is confined to the Western Hemisphere. Originally recorded in the Rocky Mountains, it is recorded in virtually all states of the United States and Central and South America. In humans, infection occurs mainly between March and September, when adult ticks are active, and people are more likely to stay in areas infected with ticks. In the southern states, sporadic cases occur throughout the year.The incidence is highest among children <15 years of age and among people who frequent tick-infested areas for work or play.

Hard-shelled ticks (family Ixodidae) are carriers of R. rickettsii. Transovarial transmission of the pathogen by ticks to their offspring is characteristic. These mites are natural carriers. D. variabilis carries the disease in the eastern and southern states of the United States. Rocky Mountain spotted fever is not likely to be transmitted directly from person to person.


Small blood vessels – sites of characteristic pathological lesions. Rickettsiae multiply within the affected endothelial cells and blood vessels can be blocked by blood clots, causing vasculitis in the skin, subcutaneous tissue, central nervous system, lungs, heart, kidneys, liver, and spleen. Disseminated intravascular coagulation often develops in critically ill patients.

Symptoms and signs of Rocky Mountain spotted fever

Between the 1st and 6th days of fever, a rash appears on the soles of the feet and forearms, which then quickly spreads to the neck, face, armpits, buttocks and trunk.Initially mottled and pink, it then becomes maculopapular and darker. After about 4 days, the skin lesions become petechial and may join to form large hemorrhagic areas that ulcerate later.

Neurological symptoms include headache, anxiety, insomnia, delirium and coma, with signs of encephalopathy. Hypotension develops in severe cases. Hepatomegaly is common, but jaundice is uncommon. Nausea and vomiting are common.Limited pneumonitis may occur. Untreated patients may develop pneumonia, tissue necrosis, and circulatory failure, sometimes with impaired brain and heart function. Cardiac arrest with sudden death sometimes occurs when the disease develops rapidly.


By the specifics of the diagnosis.

Clinicians should suspect Rocky Mountain spotted fever in any critically ill patient who lives in or near a wooded area in the Western Hemisphere and has a fever of unknown origin, headache, and general weakness.The fact of tick sucking is detected in approximately 70% of patients.

Rocky Mountain Spotted Fever Treatment

Early administration of antibiotics significantly reduces mortality, approximately 20 to 5%, and prevents most complications. If patients who have been in an endemic area have a tick suction, but there are no clinical signs, antibiotics should not be given immediately.

If fever, headache, and malaise appear (with or without rash), antibiotics should be prescribed promptly.The main treatment is doxycycline 200 mg orally once, followed by a dosage of 100 mg twice a day, until the patient improves, there is no fever for 24-48 hours, and the duration of treatment will be at least 7 days. Chloramphenicol is a 2nd line treatment.

There is no effective vaccine. Measures can be taken to prevent tick sucking.

What are the symptoms of Rocky Mountain spotted fever?

Symptoms of Rocky Mountain spotted fever occur in two stages.Initial symptoms such as headache, high fever, chills, fatigue, headache, and nausea are fairly common and the disease can be easily diagnosed. Symptoms such as diarrhea, anxiety, and delirium may develop, as well as rashes on the wrists and ankles. Among the common symptoms of Rocky Mountain spotted fever, the rash is the most common and easiest way to detect the disease.

Rocky Mountain spotted fever is a bacterial infection most commonly transmitted from a tick bite.Ticks infected with Rickettsia rickettsii , the bacteria responsible for the symptoms of the disease, are found in North America and South America. These ticks are most active during the spring and summer months, which means infection is most likely during this period.

Early symptoms of Rocky Mountain spotted fever appear within two weeks of being bitten by an infected tick. These initial symptoms appear suddenly and without warning. Tick ​​bites do not cause pain or discomfort, which means that the patient is often unaware of the bite or the impact of the disease, making early misdiagnosis more likely.

Fever is often one of the first symptoms of Rocky Mountain spotted fever to be noticed. This fever is quite high, usually reaching a temperature of at least 102 degrees Fahrenheit (38.9 degrees Celsius). Temperatures can reach 105 degrees Fahrenheit (40.5 degrees Celsius).

As with other high temperatures, this disease can cause secondary symptoms such as fatigue, chills, pain and headache. Bright light can increase pain and discomfort.Other initial symptoms include gastrointestinal disturbances such as loss of appetite, nausea, and vomiting. The patient may also experience abdominal pain.

Patients experiencing these symptoms may consult a physician. The early symptoms of Rocky Mountain spotted fever are nonspecific and resemble many other diseases. Although doctors are especially aware of the disease during the warmer months and in regions where tick bites are more common, misdiagnosis is possible in the absence of more specific symptoms, especially when ticks are not found.

Secondary symptoms usually appear within three to five days after the onset of the fever. As the disease progresses, the patient may experience anxiety, insomnia, or delirium. The patient may also be suffering from diarrhea.

During this period, the patient will also develop a rash. This patchy or patchy rash usually appears on the wrists or ankles before spreading. Rocky Mountain spotted fever is most easily identified by this rash. It should be noted, however, that this rash is not always present and may not be pronounced on dark, pigmented skin.

Treatment of Rocky Mountain spotted fever usually requires a course of antibiotics, and hospitalization may be required to resolve symptoms. This disease is life-threatening if left untreated. Even when the disease is non-fatal, fever can cause serious damage to vital organs and systems and lead to permanent debilitating illness.


90,000 Rocky Mountain spotted fever in dogs

Rocky Mountain spotted fever is one of the most common tick-borne diseases affecting dogs and humans.It belongs to the group of diseases caused by rickettsia (intracellular gram-negative microorganisms that resemble bacteria, but behave like viruses and reproduce only inside living cells). The microorganisms responsible for Rocky Mountain spotted fever parasitize ticks and are transmitted to vertebrate hosts through bites.

17 October 2013

Author: Bushaw Karina

Symptoms and types

Some dog breeds are more likely to show a stronger reaction to rickettsia than others.These include many purebred dogs, especially German shepherds. Symptoms of Rocky Mountain spotted fever vary depending on the type of microorganism the dog is infected with. Most dogs develop a fever within 5 days of being infected with rickettsia . Other symptoms:

  • Depression

  • Lethargy

  • Anorexia

  • Blood in urine

  • Irregular heart rhythm (arrhythmia)

  • Discolored patches on the skin, often with purplish or bruising

  • Inability to move normally, loss of coordination (ataxia)

  • Swelling or edema (fluid retention) of the extremities

  • Sudden bleeding, often from the nose.Blood in stool

  • Poor blood clotting, which can lead to shock or death

  • Inflammation of the lymph nodes

  • Eye pain

  • Hemorrhage, inflammation or conjunctivitis of the mucous membranes


Tick-borne diseases, caused by rickettsia.Microorganisms are carried by ticks and transmitted to animals through a bite. Most infections occur between March and October.


You will need to provide the veterinarian with a detailed medical history of the dog, describe the symptoms, recent activities of the animal, and incidents that may have led to the infection. Your story will help the veterinarian determine which organs are affected (eg, heart, kidneys).

The veterinarian will diagnose about based on blood tests , biopsies of the affected skin and symptoms.An elevated antibody level indicates an infection. To confirm the diagnosis, a laboratory study is carried out using special coloring substances.


Rocky Mountain Spotted Fever – is a serious condition that, if not properly treated , can be fatal . Treatment is usually carried out in a hospital, where medical staff can monitor the animal until its condition improves. Antibiotics may be prescribed depending on the dog’s age.It is also important to maintain proper water balance.

If your dog has low red blood cells (anemia), or is at risk of thrombocytopenia (low platelet count), the animal may need a blood transfusion.

The veterinarian will also monitor the amount of fluid in the brain to prevent edema (excessive swelling of the tissues of the brain, body, and lungs).

In addition to antibiotics, your dog may need anti-inflammatory corticosteroid medications.

Prevention and prognosis

If you live in an area where there are ticks, be sure to take precautions and regularly examine your dog. You can use tick repellents and special collars, but the best way to prevent infection is to examine the animal.

If you find a tick, put on rubber gloves and remove it (be especially careful when removing the insect’s jaws).The veterinarian may advise the use of special solutions and sprays, (given the age and health of the dog).

With proper and timely treatment, the prognosis is usually good. If you seek medical attention within a few hours of infection, the animal will most likely recover without any lasting effects.

In the absence of timely treatment, the dog can get sick or die for a long time. This can happen a few days or even hours after infection.Without proper treatment, Rocky Mountain spotted fever can have devastating effects on the central nervous system.