Rocky Mountain Spotted Fever

By | June 8, 2022

Rocky Mountain spotted fever is caused by the Rickettsia rickettsii group of bacteria. It is transmitted to humans by various tick species found in North, Central and South America. The disease is characterized by headache, high fever and a skin rash accompanying the infectious disease.

What is Rocky Mountains spotted fever?

This tick -borne infectious disease, Rocky Mountain spotted fever, is so named because it was first documented in the Rocky Mountain area of ​​the United States. It is limited to the western hemisphere. The distribution area covers the entire USA, Canada and Central and South America. For carcinoid syndrome definition, please visit

The main infection time is from March to September, when people are in the distribution areas of active, adult ticks. In the southern United States there is a risk of infection all year round. The highest incidence is in children under the age of ten and people who are in the distribution areas.


The cause is the bite of a tick infected with Rickettsia, with which the pathogen is transmitted to the human bloodstream. Humans serve as the host for the tick. Rickettsia is one of the bacteria that can only survive inside animal or human cells.

Rocky Mountain spotted fever vectors include various species of ticks such as the Ixodes tick, Dermacentor andersoni (colored tick), and Dermacentor variabilis (dog tick). Therefore, Rocky Mountain spotted fever is also known as tick bite fever. The pathological lesions stand out on the small blood vessels.

Rickettsia multiply within damaged endothelial cells. Blood vessels can become blocked by thrombi. As a result, inflammatory diseases (vasculitis) of the skin, the central nervous system and the heart, lungs, kidneys, liver and spleen occur. In the case of severe disease progression, blood coagulation occurs in the blood and lymphatic vessels distributed throughout the body.

Symptoms, Ailments & Signs

The incubation period is seven days in most cases, but can vary from three to twelve days. The shorter the contagion phase, the more severe the course of the disease. The first signs are manifested by severe headaches, chills, myalgia and prostration.

Within a few days, the body temperature rises to 40 degrees Celsius and remains at this level for 15 to 20 days in severe cases. There may be a temporary relief of symptoms in the morning. Other symptoms include loss of appetite, tiredness, nausea, vomiting, muscle pain and red eyes.

After about five days, a massive rash appears, starting on the palms of the feet and hands and then spreading over the entire body. The rash is characterized by small red spots with raised papules, which are sometimes accompanied by small bleeding (petechiae).

In contrast to the other symptoms, this rash usually causes only minor discomfort to the patient. Severe disease progression can lead to circulatory disorders, kidney failure, shock, neurological disorders and jaundice.

Diagnosis & course of disease

The combination of symptoms and course of the disease varies from case to case. Children under the age of ten, patients with delayed treatment and people with a weakened immune system are at increased risk. How severe the course of the disease is depends largely on early treatment. Treatment with antibiotics makes it possible to completely cure this infectious disease within a few days.

The diagnosis is not easy because there are no clear test methods and the symptoms can also occur with other, similar clinical pictures. If there is an initial suspicion of Rocky Mountain spotted fever, the treating doctor asks the patient about his living conditions over the past fourteen days. A clear indication of this disease are trips made by the patient to the distribution areas immediately before the appearance of the first symptoms.

If the initial suspicion is confirmed by the statements made by the person concerned, blood cultures and blood tests provide information as to whether tick bite fever is actually present. About two weeks after the onset of the disease, antibodies caused by Rickettsia rickettsii can be detected in the blood. A differential diagnosis must be made with regard to glandular fever, measles, meningitis (inflammation of the meninges) and similar viral diseases.


In the worst case, Rocky Mountain spotted fever can lead to the death of those affected. However, this only occurs if there is no treatment. This leads to circulatory disorders and ultimately to kidney failure, which can lead to death. Those affected suffer from Rocky Mountain spotted fever primarily from severe headaches and chills.

Permanent tiredness and exhaustion of the patient also occurs and has a very negative effect on the quality of life of the person concerned. There is also pain in the muscles and vomiting or nausea. The eyes are red and there may also be a rash on the skin. The liver is also negatively affected by Rocky Mountain spotted fever, so patients suffer from the symptoms of jaundice.

Due to the weakened immune system, infections or inflammations occur more frequently. Rocky Mountain spotted fever is treated with antibiotics and leads to a positive course of the disease relatively quickly. Complications usually only arise if treatment is initiated very late. If treated successfully, the patient’s life expectancy will not be adversely affected due to Rocky Mountain spotted fever.

When should you go to the doctor?

Rocky Mountain spotted fever can be severe. Since this can be deadly, one should look out for the corresponding symptoms when traveling to the American continent after a tick bite. The main infection areas are North Carolina and Oklahoma. However, rickettsia infections are widespread throughout the American continent.

The early symptoms of Rocky Mountain spotted fever are relatively nonspecific. Sudden fever after a tick bite must be taken as a warning sign. Anyone affected by tick bites should watch out for redness around the bite site or other unusual occurrences such as a sudden fever as a precaution. A visit to the doctor is advisable if headaches, diarrhea or vomiting occur as a result and without recognizable causes.

At the latest, if small purple spots appear on the wrists, forearms and ankles several days after the incident, a doctor should be consulted immediately. However, such skin bleeding (petechiae) does not occur in all tick bite patients. About half of people infected with rickettsia do not have such spots after a tick bite. Therefore, this symptom is not a reliable indicator for a visit to the doctor.

The problem with Rocky Mountain spotted fever is that it can affect the central nervous system, the gastrointestinal tract or the kidneys. To avoid a fatal outcome, the affected person should be treated with antibiotics even if Rocky Mountain spotted fever is suspected.

Treatment & Therapy

In order to rule out any consequential damage, the therapy must begin as early as possible, at the latest from the fifth day. After this time, the chances of recovery are considerably worse. This infectious disease should not be underestimated, as it can be fatal from as little as eight days without treatment. It does not matter whether the patient was previously healthy or not.

Treatment is with antibiotics from the group of tetracyclines with the active ingredient doxycycline. The drug is effective against the pathogen Rickettsia rickettsii. If this therapy is not possible, the doctor prescribes the drug chloramphenicol. In addition to these antibiotics, treatment with other drugs that counteract symptoms such as fever, pain, nausea and weakness is useful.


Probably the most effective prevention would be not to travel to the risk areas of Canada, the USA, Central and South America, since the ticks that transmit this infectious disease are only found in these regions. However, as this would be a bit of an exaggeration, the best protection is suitable clothing with long sleeves, long trousers and a hat, and sturdy shoes.

The clothing should also be secured with rubber bands at the wrists and ankles. Mosquito repellent lotions, sprays, and essential oils may provide some additional protection. Because of the smell and the composition of the substances, ticks find it more difficult to bite into the skin. After staying in the risk areas, the whole body should be checked immediately for ticks and other parasites.

Ticks are very small, the host does not notice the bite due to the anesthetic secretion. Areas of the body that are difficult to see, such as skin folds, the spaces between the toes, the hollows of the knees, the hairline and the neck should be given special attention. The sooner a tick is removed, the better the prognosis for healing.


If the course of therapy (antibiotic therapy) goes smoothly, neither follow-up examinations nor follow-up treatments are required for Rocky Mountain spotted fever. After a therapy period of seven days, the affected person is considered cured if he has been fever-free for 24 to 48 hours. At clinical discharge, regular advice on preventive measures against tick bites is offered as a follow-up measure.

Long-term effects can sometimes occur only a long time after the illness. The scope of aftercare measures then increases significantly. Long-term effects of Rocky Mountain spotted fever are deafness and damage to the gastrointestinal tract. If you experience ringing in your ears, temporary deafness or increasing abdominal pain, you should consult a doctor immediately for further examinations or treatment.

It is imperative that the doctor be informed about the previous illness with Rocky Mountain spotted fever. The risk of developing long-term effects is very low if Rocky Mountain spotted fever is treated early. In rare cases, however, the disease can be fatal. The mortality rate for the sick and treated group of people is three to ten percent. If the patient dies, follow-up care focuses on therapy for the bereaved.

For these, psychotherapy with a focus on coping with grief is generally recommended. Appropriate counseling centers must be consulted in good time. It is not possible to vaccinate against Rocky Mountain spotted fever during follow-up care. An effective vaccine has not yet been found.

You can do that yourself

Self-help for Rocky Mountain spotted fever is not possible because therapy with a broad-spectrum antibiotic is unavoidable. This should be initiated immediately if the disease is suspected, as early treatment is extremely important.

So-called tetracyclines (for example doxycycline) are usually used for treatment, to which the patients usually respond very well. Chloramphenicol is also used as a second-line drug. Penicillins, on the other hand, are not effective. For Rocky Mountain Spotted Fever (RMSF), the fatality rate for untreated cases is about 20 percent. In addition, the carrier (e.g. mites or lice) should also be combated as a precaution. In addition, the clothes of the sick must also be deloused and decontaminated.

There is no effective vaccination against Rocky Mountain spotted fever, but preventive measures against tick bites are useful. We also recommend repellents that can keep ticks, mosquitoes or horseflies away. The active ingredients contained protect against bites or stings and can therefore also prevent the transmission of diseases. The best-known active ingredients include permethrin, icaridin, DEET and various essential oils.

Rocky Mountain Spotted Fever