Rocky Mountain spotted fever
- an infectious disease characterized by high fever, pains in joints, bones, and muscles, and a cutaneous eruption, caused by rickettsii and transmitted by ticks: first reported in the Rocky Mountain area, but now more widely distributed.[1885-90, Amer.]
* * *Typhus-like disease first seen in the Rocky Mountain region, caused by the bacterium Rickettsia rickettsii (see rickettsia) and transmitted by various ticks.In severe cases the rash bleeds more and is especially prominent on the wrists and ankles. Central nervous system involvement causes restlessness, insomnia, and delirium. Prostration may progress to coma, with death possible in a week or more. Mortality increases with age. Recovery is slow but usually complete as visual disturbances, deafness, and mental confusion pass. Prompt antibiotic treatment hastens it and reduces mortality. Prevention depends on avoiding tick bites, by wearing long, light-coloured clothing and insect repellent and inspecting for ticks. A vaccine reduces the risk of infection somewhat and of death greatly.
* * *form of tick-borne typhus first described in the Rocky Mountain (Rocky Mountains) section of the United States, caused by a specific microorganism (Rickettsia rickettsii). Discovery of the microbe of Rocky Mountain spotted fever in 1906 by H.T. Ricketts (Ricketts, Howard T) led to the understanding of other rickettsial diseases. Despite its name, Rocky Mountain spotted fever is most common on the eastern coast of the United States and has been found in every state. In fact, it is identical with a disease known as São Paulo fever in Brazil and with the spotted fever of Colombia. It is a disease of the summer and early fall, when ticks are active.In western North America, the carrier species is the wood tick, Dermacentor andersoni, which is widely distributed in the adult form on large mammals, particularly cattle and sheep. In the eastern and southern United States, the common dog tick, Dermacentor variabilis, which attacks humans, also acts as a carrier. In the southwestern United States, human cases are also traced to the lone star tick, Amblyomma americanum. In Brazil the common carrier is Amblyomma cajennense.The illness begins with headache, fever, and chills, soon followed by pains in the bones and joints, weakness, and fatigue. A rash develops in the first week of illness, beginning on the extremities and spreading to the trunk. It is more profuse than the rash of epidemic typhus and affects the face as well as the body. In some people the colour of the rash deepens after a day or two, and in the worst cases it turns purple with blood. By the end of a week in severe cases, the patient shows signs of brain irritation and may be agitated, sleepless, or delirious. Breathing becomes laboured and circulation poor, and areas of gangrene may develop on the hands and feet. In the worst cases, the patient may become comatose and die, but in most cases fever gradually abates and the patient slowly recovers. Convalescence is likely to be slow and may be complicated by visual disturbances, deafness, and mental confusion. Although the patient's recovery may be delayed, it is usually complete. The case-fatality rate, as in typhus, varies directly with age.Early treatment with antibiotics greatly shortens the disease and decreases the risk of death. Prevention depends primarily upon the exercise of personal care in protection against tick bites. Persons exposed to known infected areas should frequently examine their clothing and body for ticks. Usually the tick does not become attached to its host immediately but crawls about for several hours. The chance of receiving infection from the bite of a tick is directly proportional to the length of time that the tick has fed. The ticks should be removed and the skin area involved swabbed with an antiseptic.There is a satisfactory vaccination procedure against Rocky Mountain spotted fever: the vaccine is administered in the spring or early summer before the beginning of the tick season and is repeated annually, because the maximum degree of protection conferred is for less than a year. The degree of immunity afforded is relative, but the chance for subsequent infection is lessened, and the risk of death is greatly reduced. See also boutonneuse fever.
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Rocky Mountain spotted fever — Rocky Moun·tain spotted fever räk ē mau̇nt ən n an acute bacterial disease that is characterized by chills, fever, prostration, pains in muscles and joints, and a red purple eruption and that is caused by a bacterium of the genus Rickettsia (R.… … Medical dictionary
Rocky Mountain spotted fever — ☆ Rocky Mountain spotted fever n. [from being first discovered in the ROCKY MOUNTAINS] an acute infectious disease caused by a rickettsia (Rickettsia rickettsii), transmitted to human beings by certain ticks (esp. genus Dermacentor), and… … English World dictionary
Rocky Mountain spotted fever — DiseaseDisorder infobox Name = PAGENAME Caption = Petechial rash caused by rocky mountain spotted fever on the arm ICD10 = ICD10|A|77|0|a|75 ICD9 = ICD9|082.0 ICDO = OMIM = DiseasesDB = 31130 MedlinePlus = 000654 eMedicineSubj = emerg… … Wikipedia
Rocky Mountain spotted fever — spotted fever; = tick fever a disease of rodents and other small mammals in the USA caused by the microorganism Rickettsia rickettsii and transmitted to humans by ticks. Symptoms include fever, muscle pains, and a profuse reddish rash like that… … The new mediacal dictionary
Rocky Mountain spotted fever — noun see spotted fever … English new terms dictionary
Rocky Mountain spotted fever — noun caused by rickettsial bacteria and transmitted by wood ticks • Syn: ↑mountain fever, ↑tick fever • Hypernyms: ↑spotted fever … Useful english dictionary
Rocky Mountain spotted fever — noun a disease of the typhus rickettsia group characterised by high fever, pains in joints, bones, and muscles, and a cutaneous eruption, and caused by rickettsia transmitted by ticks. It was first found in the Rocky Mountains area, North America … Australian English dictionary
Rocky Mountain spotted fever — noun Date: 1905 an acute disease that is characterized by chills, fever, prostration, pains in muscles and joints, and a red to purple eruption and that is caused by a rickettsia (Rickettsia rickettsii) usually transmitted by an ixodid tick and… … New Collegiate Dictionary
Rocky Mountain spotted fever — a disease of rodents and other small mammals in the USA caused by the microorganism Rickettsia rickettsii and transmitted to humans by ticks. Symptoms include fever, muscle pains, and a profuse reddish rash like that of measles. If untreated the… … Medical dictionary
Rocky Mountain spotted fever — n. blue disease, severe and infectious disease (highly fatal) caused by Rickettsia and is generally spread by the bite of an infected ixodid tick (its symptoms are: frontal and occipital headache, extreme lumbar pain, general discomfort,… … English contemporary dictionary