What is rickettsia

Mediterranean spotted fever is a potentially life-threatening rickettsial infection and should be suspected in patients with fever, rash, and eschar after recent travel to northern Africa or the Mediterranean basin. Rocky Mountain spotted fever is characterized by fever, headache, nausea, and abdominal pain.

Patients with murine or epidemic typhus usually present with a severe but nonspecific febrile illness, and approximately half present with a rash. Scrub typhus should be suspected in patients with a fever, headache, and myalgia after recent travel to Asia. Eschar, lymphadenopathy, cough, and encephalitis may be present. Ehrlichiosis and anaplasmosis should be suspected in febrile patients with leukopenia with an exposure history. The clinical signs are similar to those of the rickettsioses. Diagnosis is usually based on clinical recognition, epidemiologic context, and serologic testing.

Because of cross-reactivity of antigens, some antibodies may react in group-targeted serologic tests and provide evidence of exposure to the group level. PCR assays and immunohistochemical analyses may also be helpful, but useful results are highly dependent upon the type and timing of specimen submitted. If an eschar is present, a swab or biopsy sample of the lesion can be evaluated by PCR and provides a species-specific diagnosis.

If ehrlichiosis or anaplasmosis is suspected, PCR of a whole blood specimen provides the best diagnostic test. A buffy coat may provide presumptive evidence of infection if examined to identify characteristic intraleukocytic morulae. Ehrlichiosis, anaplasmosis, and spotted fever rickettsiosis are nationally notifiable diseases in the United States.

Commercial laboratories offer rickettsial testing for rickettsioses, anaplasmosis, ehrlichiosis, and scrub typhus. Treatment of patients with possible rickettsioses should begin when the disease is suspected and while awaiting confirmatory testing, as certain infections can be rapidly progressive and fatal. Immediate empiric treatment with a tetracycline is recommended for all ages, most commonly doxycycline.

Chloramphenicol may be an alternative in some cases, but its use is associated with increased risk of death, particularly from R. In some areas, tetracycline-resistant scrub typhus has been reported, and azithromycin may be an effective alternative. Limited clinical experience has shown that A.

Expert advice should be sought if alternative agents are being considered. No vaccine is available for preventing rickettsial infections. Antibiotics are not recommended for prophylaxis of rickettsial diseases and should not be given to asymptomatic people. Travelers should be instructed to minimize exposure to infectious arthropods during travel including lice, fleas, ticks, mites and to animal reservoirs particularly dogs when traveling in endemic areas.

The proper use of insect or tick repellents on skin or clothing, self-examination after visits to vector-infested areas, and wearing protective clothing are ways to reduce risk. These precautions are especially important for people with underlying conditions that may compromise their immune systems, as these people may be more susceptible to severe disease.

Note: Javascript is disabled or is not supported by your browser. People with scrub typhus have a fever, chills, and a headache Ciprofloxacin Fluoroquinolones Fluoroquinolones are a class of broad-spectrum antibiotics that are used to treat a variety of infections. Fluoroquinolones include the following: Ciprofloxacin Delafloxacin Gemifloxacin read more and other similar antibiotics may be used to treat Mediterranean spotted fever but are usually not used to treat other rickettsial or related infections.

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Common Health Topics. Rickettsial and Related Infections. Test your knowledge. Dengue is a viral infection that causes fever, aches throughout the body, and, in severe cases, bleeding in multiple areas. How is the dengue virus transmitted? More Content. Most of these infections are spread through ticks, mites, fleas, or lice.

A fever, a severe headache, and usually a rash develop, and people feel generally ill. Antibiotics are given as soon as doctors suspect one of these infections. Each species of rickettsiae and rickettsia-like bacteria has its own hosts and usually vectors. Where damage occurs and how the body responds determine which symptoms develop.

Different rickettsial infections tend to cause similar symptoms:. A doctor's evaluation. Save Word. Definition of rickettsia. Examples of rickettsia in a Sentence Recent Examples on the Web Tidewater fever, or rickettsia parkeri, is a form of Rocky Mountain spotted fever.

First Known Use of rickettsia , in the meaning defined above. Learn More About rickettsia. Time Traveler for rickettsia The first known use of rickettsia was in See more words from the same year. Statistics for rickettsia Look-up Popularity. Style: MLA. Note that this may not provide an exact translation in all languages. Home arrow-right-small-blue Topics A—Z arrow-right-small-blue Rickettsial diseases. Updated, December Rickettsial disease encompasses a group of diseases caused by the microorganisms , rickettsiae.

Rickettsiae are bacteria that can only survive inside cells. Rickettsial diseases vary considerably in severity from self-limiting mild illnesses to severe life-threatening infections , particularly if complications arise.

The organisms cause disease by damaging blood vessels in various tissues and organs. In severe cases, multiple tissues and organs are affected. Spotted fever group.