Rickettsia rickettsii

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Related to Rickettsia rickettsii: Borrelia burgdorferi, Rickettsia akari, Rickettsia prowazekii

Rick·ett·si·a rick·ett·si·i

a bacterial species, the agent of Rocky Mountain spotted fever, South African tick-bite fever, São Paulo exanthematic typhus of Brazil, Tobia fever of Colombia, and spotted fevers of Minas Gerais and Mexico; transmitted by infected ixodid ticks, especially Dermacentor andersoni and D. variabilis.

Rick·ett·si·a rick·ett·si·i

(ri-ket'sē-ă ri-ket'sē-ī)
The bacterial agent of Rocky Mountain spotted fever and its geographic variants; transmitted by infected ixodid ticks, especially Dermacentor andersoni and D. variabilis.


Howard T., U.S. pathologist, 1871-1910.
Rickettsia akari - a species causing human rickettsialpox.
Rickettsia australis - a species causing a spotted fever.
Rickettsia conrii - an African species probably causing boutonneuse fever.
Rickettsia prowazekii - a species causing epidemic typhus.
Rickettsia rickettsii - the agent of Rocky Mountain spotted fever.
Rickettsia sibirica - the agent of Siberian or North Asian tick typhus.
Rickettsia tsutsugamushi - a species causing tsutsugamushi disease and scrub typhus.
Rickettsia typhi - a species causing murine or endemic typhus fever.
rickettsial - pertaining to or caused by rickettsiae.
rickettsialpox - an acute disease caused by Rickettsia akari; transmitted by the mite.
rickettsiosis - infection with rickettsiae.
rickettsiostatic - an agent inhibitory to the growth of Rickettsia.


a genus of small, rod-shaped, round to pleomorphic microorganisms in the order Rickettsiales. They are true bacteria, gram-negative, and cultivable only in living tissues. Transmitted by lice and ticks, they cause disease in humans and domestic animals but are also found in the cytoplasm of tissue cells of lice, fleas, ticks and mites, which may act as reservoirs and vectors. See also ehrlichia and coxiella.

Rickettsia akari
causes rickettsial pox in humans, mice and rats.
Rickettsia australis
causes queensland tick typhus in humans, small marsupials, rats.
Rickettsia canadensis
causes new typhus in humans and rabbits.
Rickettsia conjunctivae
see Chlamydophila pecorum.
Rickettsia conorii
causes boutonneuse fever in humans and dogs and small feral mammals.
Rickettsia ovina
see Ehrlichia ovina.
Rickettsia phagocytophila
see Anaplasmaphagocytophila.
Rickettsia prowazeki
causes epidemic typhus in humans and possibly cattle, sheep and goats.
Rickettsia rickettsii
causes spotted fever in humans and many feral animals, especially rodents and in dogs and birds. See also rocky mountain spotted fever.
Rickettsia ruminantium
see Ehrlichiaruminantium.
Rickettsia rupricaprae
see Mycoplasmaconjunctivae.
Rickettsia sibirica
causes Siberian tick typhus in humans and many feral mammals, especially rodents.
Rickettsia tsutsugamushi
Rickettsia typhi
causes murine typhus in humans and the brown rat.
References in periodicals archive ?
Pathogenic potential of a Costa Rican strain of "Candidatus Rickettsia amblyommii" in guinea pigs (Caviaporcellus) and protective immunity against Rickettsia rickettsii.
Absence of Rickettsia rickettsii and occurrence of other spotted fever group rickettsiae in ticks from Tennessee.
Brote de Rickettsia rickettsii en Necocli, Antioquia, Colombia, 2006.
Molecular characterization of Rickettsia rickettsii isolated from Human Clinical Samples and from the Rabbit Tick Haemaphysalis leporispalustris Collected at Different Geographic Zones in Costa Rica.
Estudos in vitro comparando a susceptibilidade da Rickettsia rickettsii aos dois farmacos tambem demonstram a superioridade da doxiciclina (36, 37).
Atypical fulminant Rickettsia rickettsii infection (Brazilian spotted fever) presenting as septic shock and adult respiratory distress syndrome.
Molecular typing of isolates of Rickettsia rickettsii by use of DNA sequencing of variable intergenic regions.
Bacteria such as Rickettsia rickettsii, Rickettsia felis, Ehrlichia chaffeensis and parasitic helminths like Dipylidium caninum and Hymelonepis nana, are examples of microorganisms that are associated with ectoparasites of dogs and that also can affect humans (4).
O'Leary said that fewer than 1 in 1,000 Dermacentor ticks carry Rickettsia rickettsii, the cause of Rocky Mountain spotted fever.
Rocky Mountain spotted fever (RMSF), a tickborne infection caused by Rickettsia rickettsii and characterized by a rash (Figure), has a case-fatality rate as high as 30% in certain untreated patients (1).
Among 13 siblings of the cases, 2 had high titers of antibodies to Rickettsia rickettsii, the causative agent of RMSF.