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A rickettsia genome overrun by mobile genetic elements provides insight into the acquisition of genes characteristic of an obligate intracellular lifestyle.We present the draft genome for the Rickettsia endosymbiont of Ixodes scapularis (REIS), a symbiont of the deer tick vector of Lyme disease in North America. Among Rickettsia species (Alphaproteobacteria: Rickettsiales), REIS has the largest genome sequenced to date (>2 Mb) and contains 2,309 genes across the chromosome and four plasmids (pREIS1 to pREIS4). The most remarkable finding within the REIS genome is the extraordinary proliferation of mobile genetic elements (MGEs), which contributes t ...201222056929
etiology of acute, non-malaria, febrile illnesses in jayapura, northeastern papua, indonesia.abstract. we conducted a prospective, inpatient fever study in malaria-endemic papua, indonesia to determine non-malaria fever etiologies. investigations included malaria blood films, blood culture, paired serologic samples analysis for dengue, japanese encephalitis, leptospirosis, scrub typhus, murine typhus, and spotted fever group rickettsia. during 1997-2000, 226 patients (127 males and 99 females) 1-80 years of age (median age = 25 years) were enrolled. positive blood cultures (n = 34, 15%) ...201222232450
rickettsiae in arthropods collected from the north african hedgehog (atelerix algirus) and the desert hedgehog (paraechinus aethiopicus) in algeria.hedgehogs have become a popular pet despite their potential role in zoonotic disease transmission. we conducted an entomological study in a mountainous region of northeast algeria in which we collected 387 fleas (archeopsylla erinacei) and 342 ticks (rhipicephalus sanguineus and haemaphysalis erinacei) from paraechinus aethiopicus and atelerix algirus hedgehogs. of the hedgehogs sampled, 77.7% and 91% were infested with fleas and ticks, respectively. significantly more ticks and fleas were colle ...201222222114
first report on the occurrence of rickettsia slovaca and rickettsia raoultii in dermacentor silvarum in china.abstract: background: rickettsioses are among both the longest known and most recently recognized infectious diseases. although new spotted fever group rickettsiae have been isolated in many parts of the world including china, little is known about the epidemiology of rickettsia pathogens in ticks from xinjiang autonomous region of china. methods: in an attempt to assess the potential risk of rickettsial infection after exposure to ticks in xinjiang uygur autonomous region of china, a total of ...201222257726
spotted fever group rickettsia in yunnan province, china.abstract information about spotted fever group (sfg) rickettsiae in southern china remains sparse. a specific and sensitive real-time pcr assay for detection of sfg rickettsiae was established and used to detect the prevalence rate of sfg rickettsiae in yunnan province, china. the limit of detection (lod) of our real-time pcr was 200 copies per reaction, which is more sensitive than the previously developed nested pcr assays for rickettsia. we tested 265 blood samples (127 goats, 78 dogs, and ...201222225423
The rhizome of life: the sympatric Rickettsia felis paradigm demonstrates the random transfer of DNA sequences.The intracellular flea symbiont, Rickettsia felis, may meet other organisms intracellularly such as R. typhi. We used a single-gene phylogenetic approach of the 1375 R. felis genes to look for horizontal transfers that occurred as a result of the bacterial promiscuity with other organisms. Our results showed that besides genes that are linked to the Spotted Fever Group, 165 genes have a different history and are linked to other Rickettsia such as R. bellii (107 genes), R. typhi (15 genes), or to ...201122024628
complementation of rickettsia rickettsii rela/spot restores a nonlytic plaque phenotype.spotted fever group rickettsiae are known to produce distinct plaque phenotypes. strains that cause lytic infections in cell culture form clear plaques, while nonlytic strains form opaque plaques in which the cells remain intact. clear plaques have historically been associated with more-virulent species or strains of spotted fever group rickettsiae. we have selected spontaneous mutant pairs from two independent strains of rickettsia rickettsii, the virulent r strain and the avirulent iowa strain ...201121300770
gotch ear in a goat: a case report.abstract a 1-year-old castrated male saanen goat was observed to have drooping and edema of the left ear consistent with published accounts of gotch ear in cattle associated with a tick bite. the goat's left ear was edematous from the tip of the pinna to the base of the ear. no signs of trauma or infectious processes were observed. three engorged gulf coast ticks (amblyomma maculatum) were observed attached inside the ear. ticks were removed and the ear biopsied at tick attachment sites. the aff ...201121395411
spotted fever group rickettsia infecting ticks (acari: ixodidae) in the state of santa catarina, brazil.during 2006-2008, a total of 260 adult ticks were collected from domestic and wild animals in different regions of the state of santa catarina (sc), brazil, including areas where human cases of brazilian spotted fever have been reported. collected ticks belonging to nine species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, amblyomma longirostre, amblyomma ovale, amblyomma tigrinum, dermacentor nitens, rhipicephalus microplus and rhipicephalus sanguineus) were tested by polym ...201122241112
widespread use of real-time pcr for rickettsial diagnosis.we report 2 years of experience with rickettsial molecular diagnosis using real-time pcr at the french national reference center. all rickettsia genomes available were compared to discover specific sequences to design new sets of primers and probes. the specificity was verified in silico and against a panel of 30 rickettsial species. sensitivity was determined using 10-fold serial dilutions. finally, primers and probes that were both specific and sensitive were routinely used for the diagnosis o ...201122092999
high rates of rickettsia parkeri infection in gulf coast ticks (amblyomma maculatum) and identification of "candidatus rickettsia andeanae" from fairfax county, virginia.the gulf coast tick, amblyomma maculatum, is a vector of rickettsia parkeri, a recently identified human pathogen that causes a disease with clinical symptoms that resemble a mild form of rocky mountain spotted fever. because the prevalence of r. parkeri infection in geographically distinct populations of a. maculatum is not fully understood, a. maculatum specimens collected as part of a tick and pathogen surveillance system in fairfax county, virginia, were screened to determine pathogen infect ...201121867421
Rickettsia parkeri invasion of diverse host cells involves an Arp2/3 complex, WAVE complex and Rho-family GTPase-dependent pathway.Rickettsiae are obligate intracellular pathogens that are transmitted to humans by arthropod vectors and cause diseases such as spotted fever and typhus. Although rickettsiae require the host cell actin cytoskeleton for invasion, the cytoskeletal proteins that mediate this process have not been completely described. To identify the host factors important during cell invasion by Rickettsia parkeri, a member of the spotted fever group (SFG), we performed an RNAi screen targeting 105 proteins in Dr ...201122188208
short report: new spotted fever group rickettsia in a rhipicephalus turanicus tick removed from a child in eastern sicily, italy.a new genotype of spotted fever group rickettsia (sfgr) was identified in rhipicephalus turanicus from eastern sicily. on the basis of current molecular criteria, the genetic characteristics obtained from multiple locus sequence typing satisfy the requirements for candidatus status of this sfgr. further detection and identification of this sfgr during entomological and clinical surveys will be required to establish the prevalence of this rickettsia and its potential pathogenicity for humans.201121212209
a focus of dogs and rickettsia massiliae-infected rhipicephalus sanguineus in california.a recurrent focus of rhipicephalus sanguineus infestation was investigated in a suburban area of southern california after reports of suspected rocky mountain spotted fever in two dogs on the same property. abundant quantities of rh. sanguineus were collected on the property and repeatedly from each dog, and rickettsia massiliae dna was detected by polymerase chain reaction (pcr). whole blood and serum samples from four dogs were tested by using pcr and microimmunofluorescent assay for antibodie ...201121292893
Evaluation of clinical specimens for Rickettsia, Bartonella, Borrelia, Coxiella, Anaplasma, Franciscella and Diplorickettsia positivity using serological and molecular biology methods.We monitored clinical samples from patients of different age groups from selected regions in Slovakia. Overall seroprevalence evaluated by immunofluorescence (IFA) using nine Bartonella, two Borrelia, six rickettsial (spotted fever and typhus group), two Coxiella, and one human granulocytic ehrlichiosis Anaplasma, Franciscella tularensis and Diplorickettsia massiliensis antigens, in rural and city populations of Slovak Republic, was found to be 32% positive for spotted fever group rickettsiae. O ...201122098390
Molecular detection of rickettsial agents in ticks and fleas collected from a European hedgehog (Erinaceus europaeus) in Marseilles, France.The European hedgehog (Erinaceus europaeus) is a synanthropic nocturnal insectivore commonly found in the countryside and in the parks and gardens. Because hedgehogs are already involved in the transmission of a number of zoonoses, including salmonellosis and ringworm, we decided to study their possible role in the epidemiology of the spotted fever group of Rickettsia. We collected ticks and fleas from a hedgehog that was captured in the city of Marseilles in France. Using a genus-specific quant ...201122169021
Molecular evidence of Rickettsia felis infection in dogs from Northern Territory, Australia.The prevalence of spotted fever group rickettsial infection in dogs from a remote indigenous community in the Northern Territory (NT) was determined using molecular tools. Blood samples collected from 130 dogs in the community of Maningrida were subjected to a spotted fever group (SFG)-specific PCR targeting the ompB gene followed by a Rickettsia felis-specific PCR targeting the gltA gene of R. felis. Rickettsia felis ompB and gltA genes were amplified from the blood of 3 dogs. This study is the ...201121989454
dose-response model of rocky mountain spotted fever (rmsf) for human.rickettsia rickettsii is the causative agent of rocky mountain spotted fever (rmsf) and is the prototype bacterium in the spotted fever group of rickettsiae, which is found in north, central, and south america. the bacterium is gram negative and an obligate intracellular pathogen. the disease is transmitted to humans and vertebrate host through tick bites; however, some cases of aerosol transmission also have been reported. the disease can be difficult to diagnose in the early stages, and withou ...201121453373
transmission electron microscopy as a tool for exploring bacterial proteins: model of ricka in rickettsia conorii.rickettsia conorii, the etiologic agent of mediterranean spotted fever, belongs to the spotted fever group of rickettsia. it is an obligate intracellular bacterium that grows within the cytoplasm of its eukaryotic host cells. it is motile in the cytoplasm of infected cells and ricka is reported as critical protein in this aspect. however, the subcellular localization of ricka remains uncertain. we describe a simple method allowing ricka protein to be localized by immunofluorescence assay (ifa) a ...201121617834
distribution of spotted fever group rickettsiae in select tissues of experimentally infected and field-collected gulf coast ticks.salivary glands, midgut, malpighian tubules, and ovaries were dissected from infected, colony-derived amblyomma maculatum (gulf coast ticks) injected as nymphs with either rickettsia parkeri (a spotted fever group rickettsia [sfgr]; treatment) or phosphate-buffered saline (negative control). for comparison, similar tissues were dissected from hemolymph-positive, field-collected ticks. tissues were analyzed by indirect fluorescent antibody (ifa) tests. all phosphate-buffered saline-injected ticks ...201121661331
molecular diagnostics of rickettsia africae infection in travelers returning from south africa to the netherlands.abstract background: african tick-bite fever (atbf) is frequently diagnosed in the netherlands in travelers returning from south africa. it is caused by rickettsia africae and diagnosis is based on travel history and clinical presentation and usually confirmed by detecting serum antibodies against rickettsiae of the spotted fever group. however, these typically occur late in the course of the disease, and a mild clinical course or early antibiotic treatment can diminish antibody production. ...201121867422
israeli spotted fever, tunisia.to the editor: mediterranean spotted fever (msf) caused by rickettsia conorii was the first rickettsiosis described in tunisia. r. conorii was thought to be the only species existing in this country. however, authors reported other rickettsioses either from spotted fever group or typhus group (1,2). in sfax, a town in southern tunisia, physicians noted patients with severe forms of msf and suspected the presence of other species or a virulent r. conorii strain. we report 2 cases of israeli spott ...201121762610
q fever, spotted fever group, and typhus group rickettsioses among hospitalized febrile patients in northern tanzania.background. the importance of q fever, spotted fever group rickettsiosis (sfgr), and typhus group rickettsiosis (tgr) as causes of febrile illness in sub-saharan africa is unknown; the putative role of q fever as a human immunodeficiency virus (hiv) coinfection is unclear. methods. we identified febrile inpatients in moshi, tanzania, from september 2007 through august 2008 and collected acute- and convalescent-phase serum samples. a ≥4-fold increase in immunoglobulin (ig) g immunfluorescence ass ...201121810740
[emergence of tick-borne spotted fever group rickettsiosis in moscow].analysis of clinical cases of tick-borne spotted fever (tsf) group rickettsiosis in 2005 - 2010.201121809650
tick infestation and spotted-fever group rickettsia in shelter dogs, california, 2009.in response to an outbreak of rocky mountain spotted fever (rmsf) in baja california in early 2009, dogs at two shelters in neighbouring imperial county, california, were evaluated for ectoparasites. brown dog ticks (rhipicephalus sanguineus), a recognized vector for rmsf, were found on 35 (30%) of 116 dogs but all ticks tested negative for rickettsia rickettsii by pcr.201121824367
molecular detection and identification of rickettsia species in ixodes pacificus in california.we amplified 16s rrna, glta, and ompa genes from ixodes pacificus by polymerase chain reaction. sequencing, blast analysis, and phylogenetic constructions indicated that two rickettsia phylotypes are present in i. pacificus. while phylotype g021 has high homology to ixodes scapularis endosymbiotic rickettsia, phylotype g022 is a deeply branched novel spotted fever group rickettsia.201121413886
infection by spotted fever rickettsiae in people, dogs, horses and ticks in londrina, parana state, brazil.spotted fever is a disease caused by bacteria from the genus rickettsia of the spotted fever group (sfg). rickettsia rickettsii is likely the main agent of brazilian spotted fever (bsf). with the objective of gathering information on the circulation of sfg rickettsiae in londrina, parana state, ticks from dogs and horses and also blood from dogs, horses and humans were collected in a neighbourhood of the city which presented potential for circulation of rickettsiae between hosts and vectors. amb ...201121824336
rickettsial diseases in central india: proposed clinical scoring system for early detection of spotted fever.objectives: to report a series of cases of rickettsial infections from central india and to develop a clinical scoring system for its early detection. design: retrospective review of children hospitalized during one year period with fever without a source, and presence of one or more of the clinical features suggestive of rickettsial infection. diagnosis of rickettsial disease was made by classical clinical features and detection of igm antibody by elisa. a clinical scoring system was developed ...201121555807
rickettsia felis: from a rare disease in the usa to a common cause of fever in sub-saharan africa.rickettsia felis is a spotted fever group rickettsia that has been definitely described in 2002. within the last 20 years, there have been a growing number of reports implicating r. felis as a human pathogen, parallel to the fast-growing reports of the worldwide detection of r. felis in arthropod hosts, mainly the cat flea ctenocephalides felis felis. r. felis is now known as the agent of the so-called flea-borne spotted fever, with more than 70 cases documented in the literature. recently, two ...201121722253
Detection of Rickettsia parkeri and Candidatus Rickettsia andeanae in Amblyomma maculatum Gulf Coast Ticks Collected from Humans in the United States.Abstract Rickettsia parkeri, a spotted fever group (SFG) rickettsia recently found to be pathogenic to humans, causes an eschar-associated febrile illness. The R. parkeri rickettsiosis, Tidewater spotted fever, has been misdiagnosed as Rocky Mountain spotted fever due to serologic cross reactivity and the lack of specific diagnostic methods. Candidatus Rickettsia andeanae, also a SFG rickettsia, is a recently described agent of unknown pathogenicity originally identified in ticks collected fro ...201122022815
in vitro propagation of candidatus rickettsia andeanae isolated from amblyomma maculatum.candidatus rickettsia andeanae was identified during an investigation of a febrile outbreak in northwestern peru (2002). dna sequencing from two ticks (amblyomma maculatum, ixodes boliviensis) collected during the investigation revealed a novel rickettsia agent with similarity to the spotted fever group rickettsiae. since then, candidatus r. andeanae has been detected in a. maculatum ticks collected in the southeastern and southcentral united states, argentina, and peru. to date, candidatus r. a ...201122098316
restriction of the growth of a nonpathogenic spotted fever group rickettsia.the growth kinetics of pathogenic and nonpathogenic rickettsiae were compared to elucidate the mechanism responsible for the pathogenicity of rickettsiae. vero and hela cells derived from mammals were inoculated with a nonpathogenic species of spotted fever group rickettsia, rickettsia montanensis, before being infected with the pathogenic species rickettsia japonica. the mammalian cells became persistently infected with r. montanensis and produced low levels of rickettsiae. on the other hand, s ...201122066520
[surveillance of rickettsia sp. infection in capybaras (hydrochoerus hydrochaeris) a potential model of epidemiological alert in endemic areas].introduction. capybaras (hydrochoerus hydrochaeris) are considered amplifying hosts of rickettsia sp. these rodents are usually parasitized by the tick vector, amblyomma cajennense, the main vector of rickettsioses in humans and animals in south america. capybaras can be used as sentinels in detection of circulation of rickettsiae. objective. antibodies to rickettsiae of spotted fever group were detected in capybaras in a rural area of cordoba province, northern colombia. materials and methods. ...201122159538
life cycle, growth characteristics and host cell response of rickettsia helvetica in a vero cell line.rickettsia helvetica, a spotted fever rickettsia and emerging pathogen with ixodes ricinus ticks as the main vector, is an agent of human disease and may cause febrile illness as well as meningitis. in three parallel series the isolated standard type of r. helvetica, obtained from a pcr-positive i. ricinus tick, was high-passaged and propagated in a vero cell line. by using quantitative real-time pcr, the generation time from inoculation to stationary phase of growth was calculated to 20-22 h. i ...201122116301
Study of infection by Rickettsiae of the spotted fever group in humans and ticks in an urban park located in the City of Londrina, State of Paraná, Brazil.Spotted fevers are emerging zoonoses caused by Rickettsia species in the spotted fever group (SFG). Rickettsia rickettsii is the main etiologic agent of Brazilian spotted fever (BSF)and it is transmitted by Amblyomma spp. ticks.201121901874
spotted fever group rickettsiae in ticks collected from wild animals in israel.we report molecular evidence for the presence of spotted fever group rickettsiae (sfgr) in ticks collected from roe deer, addax, red foxes, and wild boars in israel. rickettsia aeschlimannii was detected in hyalomma marginatum and hyalomma detritum while rickettsia massiliae was present in rhipicephalus turanicus ticks. furthermore, a novel uncultured sfgr was detected in haemaphysalis adleri and haemaphysalis parva ticks from golden jackals. the pathogenicity of the novel sfgr for humans is unk ...201122049050
An unusual case of fatal pulmonary hemorrhage in pregnancy.Rickettsial diseases are common in Srilanka. The spotted fever group of rickettsiae presents in many ways, including very severe disease causing significant morbidity and mortality. A regional variation of the Rickettsia conorii subspecies and differences in clinical presentations are reported. This case describes disseminated Rickettsia conorii infection in a pregnant woman presenting with endocarditis.201121886958
detection of babesia sp. eu1 and members of spotted fever group rickettsiae in ticks collected from migratory birds at curonian spit, north-western russia.to reveal the prevalence of spotted fever group (sfg) rickettsiae and babesia sp. in ixodes ricinus (l.) ticks from migratory birds, 236 specimens represented 8 species of passeriformes and were collected at curonian spit in kaliningrad enclave of north-western russia. the ticks (total 126) being detached from four bird species, turdus philomelos, fringilla coelebs, parus major, and sturnus vulgaris, were investigated by pcr using the primers rp cs.877p/rp cs.1258n for the detection of rickettsi ...201120553110
evidence of exposure to spotted fever group rickettsiae among arizona dogs outside a previously documented outbreak area.since 2003, two communities in eastern arizona have experienced a sustained outbreak of rocky mountain spotted fever (rmsf), caused by rickettsia rickettsii, associated with transmission by rhipicephalus sanguineus, the brown dog tick; 70 human cases, including eight deaths, were reported from these communities during 2003 through 2008. in both of the affected communities, antibodies to spotted fever group rickettsiae (sfgr) were present in dogs before the notice of the first human cases, sugges ...201120042069
identification of potential hosts and vectors of scrub typhus and tick-borne spotted fever group rickettsiae in eastern taiwan.scrub typhus and tick-borne spotted fever group (sfg) rickettsioses are transmitted by chiggers (larval trombiculid mites) and hard ticks, respectively. we assessed exposure to these disease vectors by extensively sampling both chiggers and ticks and their small mammal hosts in eastern taiwan during 2007 and 2008. the striped field mouse apodemus agrarius pallas (rodentia: muridae) was the most common of the small mammals (36.1% of 1393 captures) and presented the highest rate of infestation wit ...201121223345
arthropod vectors and vector-borne bacterial pathogens in yosemite national park.ticks, fleas, and vector-borne pathogens were surveyed in diverse small mammals in yosemite national park, california, from 2005 to 2007. a total of 450 unique captures of small mammals was collected during a 3-yr period and yielded 16 species of fleas and 10 species of ticks, including known vectors of anaplasma phagocytophilum and borrelia burgdorferi and plague. serology was performed for a. phagocytophilum, spotted fever group rickettsia spp., b. burgdorferi, and yersinia pestis. a. phagocyt ...201121337955
risk factors for african tick-bite fever in rural central africa.african tick-bite fever is an emerging infectious disease caused by the spotted fever group rickettsia, rickettsia africae, and is transmitted by ticks of the genus amblyomma. to determine the seroprevalence of exposure to r. africae and risk factors associated with infection, we conducted a cross-sectional study of persons in seven rural villages in distinct ecological habitats of cameroon. we examined 903 plasma samples by using an indirect immunofluorescence assay for antibodies to r. africae ...201121460018
prevalence of lyme disease agents and several emerging pathogens in questing ticks from the german baltic coast.in summer 2008, a total of 512 ixodes ricinus (acari: ixodidae) ticks was collected from vegetation in four areas at the baltic coast of germany and tested for the presence of lyme disease spirochetes. among them, 293 ticks from three areas were screened for anaplasma phagocytophilum (rickettsiales: anaplasmataceae), rickettsiae of the spotted fever group (rickettsiales: rickettsiaceae), and babesia spp. (piroplasmida: babesiidae), respectively. borrelia burgdorferi sensu lato genospecies (spiro ...201121485387
rickettsia rickettsii (rickettsiales: rickettsiaceae) in amblyomma americanum (acari: ixodidae) from kansas.the role of lone star ticks as vectors for rocky mountain spotted fever (rmsf) remains poorly described. we compared the entomological inoculation rates (eirs) for rickettsia spp. for representative sites in missouri and kansas, states that frequently report rmsf each year. host-seeking ticks were collected during 2006 and pooled tick homogenates analyzed by polymerase chain reaction to detect probable r. rickettsii, with confirmation for multiple gene targets performed on individual ticks from ...201121485390
detection of spotted fever group rickettsia in haemaphysalis longicornis in hebei province, china.abstract dna samples from 737 ticks pools, representing 6850 haemaphysalis longicornis and 51 dermacentor nuttalli ticks collected from hebei province, china, were analyzed by pcr for the presence of spotted fever group rickettsia. there were 50 (6.9%) of 724 h. longicornis ticks pools found positive, but no positive samples found in 13 d. nuttalli. sequence analysis of the partial outer membrane protein a (ompa) genes from the ten positive samples showed 98% identity, but different from the hom ...201121506802
spotted fever group rickettsiae in ticks, germany.to explore increased risk for human rickettsia spp. infection in germany, we investigated recreational areas and renatured brown coal surface-mining sites (also used for recreation) for the presence of spotted fever group rickettsiae in ticks. r. raoultii (56.7%), r. slovaca (13.3%), and r. helvetica (>13.4%) were detected in the respective tick species.201121529404
molecular evidence supports the role of dogs as potential reservoirs for rickettsia felis.abstract rickettsia felis causes flea-borne spotted fever in humans worldwide. the cat flea, ctenocephalides felis, serves as vector and reservoir host for this disease agent. to determine the role of dogs as potential reservoir hosts for spotted fever group rickettsiae, we screened blood from 100 pound dogs in southeast queensland by using a highly sensitive genus-specific pcr. nine of the pound dogs were positive for rickettsial dna and subsequent molecular sequencing confirmed amplification o ...201121612534
detection of rickettsia conorii strains in portuguese dogs (canis familiaris).this study reports a serological and molecular survey on the spotted fever group rickettsia found in a group of 51 dogs with suspected tick-borne illness from the south of portugal. additionally, a prevalence of igg antibodies to r. conorii was also estimated in a group of 400 healthy dogs from the same region. in the group of healthy dogs, the immunofluorescence test revealed that 154 (38.5%) of the 400 dogs had igg antibodies reactive with r. conorii. the highest proportion of dogs (45%) with ...201121771547
molecular detection of rickettsia massiliae, rickettsia sibirica mongolitimonae and rickettsia conorii israelensis in ticks from israel.rickettsioses are recognized as important emerging vector-borne infections of humans worldwide. previous reports documented the presence of two spotted fever group rickettsiae in israel, rickettsia conorii israelensis and rickettsia felis. the aim of this study was to characterize the diversity of rickettsiae in ticks collected from vegetation and the ground, from different parts of israel. non-engorged questing adult ticks were collected from 13 localities. a total of 131 tick pools, 83 of rhip ...201120331680
tick-borne lymphadenopathy (tibola) acquired in southwestern germany.tick-borne lymphadenopathy (tibola) was first described in 1997 in a patient in france. the causative agent, rickettsia slovaca, is transmitted by dermacentor ticks.201121663601
spotted fever group rickettsiae in ticks in cyprus.in two surveys conducted from march 1999 to march 2001 and from january 2004 to december 2006, a total of 3,950 ticks (belonging to ten different species) were collected from seven domestic and wild animals (goat, sheep, cattle, dog, fox, hare, and mouflon) from different localities throughout cyprus. in order to establish their infection rate with spotted fever rickettsiae (sfg), ticks were pooled and tested by polymerase chain reaction targeting glta and ompa genes, followed by sequencing anal ...201121833539
rickettsial evolution in the light of comparative genomics.rickettsia are best known as strictly intracellular vector-borne bacteria that cause mild to severe diseases in humans and other animals. recent advances in molecular tools and biological experiments have unveiled a wide diversity of rickettsia spp. that include species with a broad host range and some species that act as endosymbiotic associates. molecular phylogenies of rickettsia spp. contain some ambiguities, such as the position of r. canadensis and relationships within the spotted fever gr ...201120716256
cattle and the natural history of rickettsia parkeri in mississippi.abstract cattle have been recognized as hosts for amblyomma maculatum, the gulf coast tick, for over 100 years. for nearly as long, a. maculatum have been known to harbor the spotted fever group rickettsia (sfgr), now known as rickettsia parkeri. however, human infection with r. parkeri was not documented until 2004. results presented herein describe a laboratory and a field study evaluating cattle and the natural history of a. maculatum and r. parkeri in mississippi. in the laboratory study, se ...201120846012
tick-borne disease agents in various wildlife from mississippi.because tick-borne diseases are becoming increasingly important throughout the world, monitoring their causative agents in wildlife may serve as a useful indicator of potential human exposure. we assessed the presence of known and putative zoonotic, tick-borne agents in four wildlife species in mississippi. animals were tested for exposure to or infection with ehrlichia chaffeensis, ehrlichia ewingii, borrelia lonestari, rickettsia spp., anaplasma phagocytophilum, and francisella tularensis. who ...201120846016
tick-borne rickettsioses, neglected emerging diseases in rural senegal.rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in west africa.201020856858
pathogens and symbionts in ticks: a survey on tick species distribution and presence of tick-transmitted micro-organisms in sardinia, italy.a total of 1485 adult ticks were collected from mammalian hosts in south-eastern sardinia, italy, during the years 2007-2008. ticks were identified and tested by pcr analysis for presence of rickettsia species of the spotted fever group, ehrlichia canis, anaplasma phagocytophilum, coxiella burnetii, bartonella species and leishmania species. among all tick species examined (rhipicephalus sanguineus, rhipicephalus turanicus, rhipicephalus bursa, rhipicephalus pusillus, hyalomma marginatum margina ...201020884769
rickettsia spp. in wild small mammals in lower bavaria, south-eastern germany.abstract so far, data on the natural cycle of rickettsiae of the tick-borne spotted fever group (sfg) in central europe are barely available. some studies showed the occurrence of different rickettsia species in their arthropod vectors, but it is unclear which animals might have any kind of reservoir function. this survey was therefore set up to provide information on the occurrence of sfg rickettsiae in small mammals in germany. a total of 124 rodents and insectivores were collected over a peri ...201020925521
a kunitz protease inhibitor from dermacentor variabilis, a vector for spotted fever group rickettsiae, limits rickettsia montanensis invasion.a defining facet of tick-rickettsia symbioses is the molecular strategy employed by each partner to ensure its own survival. ticks must control rickettsial colonization to avoid immediate death. in the current study, we show that rickettsial abundance in the tick midgut increases once the expression of a kunitz-type serine protease inhibitor from the american dog tick (dermacentor variabilis) (dvkpi) is suppressed by small interfering rna (sirna). a series of in vitro invasion assays suggested t ...201020956566
coexistence of pathogens in host-seeking and feeding ticks within a single natural habitat in central germany.the importance of established and emerging tick-borne pathogens in central and northern europe is steadily increasing. in 2007, we collected ixodes ricinus ticks feeding on birds (n = 211) and rodents (n = 273), as well as host-seeking stages (n = 196), in a habitat in central germany. in order to find out more about their natural transmission cycles, the ticks were tested for the presence of lyme disease borreliae, anaplasma phagocytophilum, spotted fever group (sfg) rickettsiae, francisella tu ...201020729315
absence of rickettsia rickettsii and occurrence of other spotted fever group rickettsiae in ticks from tennessee.rocky mountain spotted fever (rmsf) is the most common tick-borne illness in tennessee. little is known about the occurrence of r. rickettsii, the causative agent, in ticks in tennessee. to better understand the prevalence and distribution of rickettsial agents in ticks, we tested 1,265 amblyomma, dermacentor, and ixodes adult and nymphal ticks. additionally, we tested 231 amblyomma americanum larvae. ticks were collected from 49 counties from humans, wild animals, domestic canines, and flannel ...201020810834
rickettsia infection in dogs and rickettsia parkeri in amblyomma tigrinum ticks, cochabamba department, bolivia.only few published data are available on ticks and tick-borne zoonotic pathogens in bolivia. to evaluate rickettsial seroprevalence and infection in dogs and ticks, during february-april 2007, we collected whole blood, sera, and ticks from dogs living in the rural, peri-urban, and urban areas of cochabamba, bolivia. dog sera were subjected to enzyme-linked immunosorbent assay test to detect igg antibodies against rickettsia rickettsii and 68.2% of samples were found to be positive (n = 30; 95% c ...201020426684
ecological factors characterizing the prevalence of bacterial tick-borne pathogens in ixodes ricinus ticks in pastures and woodlands.ecological changes are recognized as an important driver behind the emergence of infectious diseases. the prevalence of infection in ticks depends upon ecological factors that are rarely taken into account simultaneously. our objective was to investigate the influences of forest fragmentation, vegetation, adult tick hosts, and habitat on the infection prevalence of three tick-borne bacteria, borrelia burgdorferi sensu lato, anaplasma phagocytophilum, and rickettsia sp. of the spotted fever group ...201020453131
bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial organisms.in north carolina, reported human cases of tick-borne illness, specifically rocky mountain spotted fever, have escalated over the past decade. to determine the relative abundance of vectors and to estimate the risk of acquiring a tick-borne illness in peri-residential landscapes, ticks were collected in chatham county, a typical piedmont county and, samples of the ticks were tested for infection with selected bacterial pathogens using real-time quantitative polymerase chain reaction assays. tick ...201020455778
host associations of dermacentor, amblyomma, and ixodes (acari: ixodidae) ticks in tennessee.from april 2007 to september 2008, 1,793 adult and nymphal ixodid ticks were collected from 49 counties in tennessee. six species were identified, including dermacentor variabilis (say), amblyomma americanum (l.), ixodes texanus (banks), ixodes cookei packard, ixodes scapularis (say), and amblyomma maculatum koch, from 13 medium- to large-sized mammalian hosts and dragging through vegetation. raccoons were the most common vertebrate source (198 captures), accounting for 60% of ticks collected. d ...201020496589
high prevalence of tick-borne pathogens in dogs from an indian reservation in northeastern arizona.we evaluated the serological and molecular prevalence of selected organisms in 145 dogs during late spring (may/june) of 2005 and in 88 dogs during winter (february) of 2007 from the hopi indian reservation. additionally, in 2005, 442 ticks attached to dogs were collected and identified as rhipicephalus sanguineus. infection with or exposure to at least one organism was detected in 69% and 66% of the dogs in may/june 2005 and february 2007, respectively. exposure to spotted fever group (sfg) ric ...201019469667
prevalence of five pathogenic agents in questing ixodes ricinus ticks from western france.in europe, ixodes ricinus ticks are vectors of many emerging pathogens, including borrelia burgdorferi sensu lato (sl), anaplasma phagocytophilum, spotted fever group rickettsia sp., babesia sp., and very likely bartonella sp. in this study, we looked for the presence of dna of these microorganisms in 572 ticks from two forests in the west of france. dna extraction and polymerase chain reaction (pcr) amplification were performed on individual nymphal, male, and female i. ricinus ticks. amplifica ...201020020814
evaluation of brain tissue or cerebrospinal fluid with broadly reactive polymerase chain reaction for ehrlichia, anaplasma, spotted fever group rickettsia, bartonella, and borrelia species in canine neurological diseases (109 cases).vector-transmitted microorganisms in the genera ehrlichia, anaplasma, rickettsia, bartonella, and borrelia are commonly suspected in dogs with meningoencephalomyelitis (mem), but the prevalence of these pathogens in brain tissue and cerebrospinal fluid (csf) of dogs with mem is unknown.201020102497
serological prevalence study of exposure of cats and dogs in launceston, tasmania, australia to spotted fever group rickettsiae.a sero-epidemiological study of cats and dogs in the launceston area of tasmania, australia was undertaken to determine the prevalence of antibodies to spotted fever group (sfg) rickettsiae. results showed that 59% of cats and 57% of dogs were positive for antibodies, but there was no correlation between the animal's health and seropositivity at the time of testing, suggesting that rickettsial exposure is unrelated to ill-health in these two species of domestic animals.201020148824
the rickettsia conorii autotransporter protein sca1 promotes adherence to nonphagocytic mammalian cells.the pathogenesis of spotted fever group (sfg) rickettsia species, including r. conorii and r. rickettsii, is acutely dependent on adherence to and invasion of host cells, including cells of the mammalian endothelial system. bioinformatic analyses of several rickettsia genomes revealed the presence of a cohort of genes designated sca genes that are predicted to encode proteins with homology to autotransporter proteins of gram-negative bacteria. previous work demonstrated that three members of thi ...201020176791
disruption of the rickettsia rickettsii sca2 autotransporter inhibits actin-based motility.rickettsii rickettsii, the etiologic agent of rocky mountain spotted fever, replicates within the cytosol of infected cells and uses actin-based motility to spread inter- and intracellularly. although the ultrastructure of the actin tail and host proteins associated with it are distinct from those of listeria or shigella, comparatively little is known regarding the rickettsial proteins involved in its organization. here, we have used random transposon mutagenesis of r. rickettsii to generate a s ...201020194597
rickettsia helvetica in patient with meningitis, sweden, 2006.pathogenicity of rickettsia helvetica is relatively unknown. we isolated a spotted fever group rickettsial organism from a patient with subacute meningitis. nucleotide sequences of the 16s rrna, ompb, and 17kda genes identified the isolate as r. helvetica. this organism may be associated with serious infections such as central nervous system disorders.201020202426
novel spotted fever group rickettsiosis, brazil.we report a clinical case of spotted fever group rickettsiosis acquired in sao paulo, brazil. definitive diagnosis was supported by seroconversion between acute-phase and convalescent-phase serum samples. molecular analysis of skin samples indicated the agent was a novel spotted fever group strain closely related to rickettsia africae, r. parkeri, and r. sibirica.201020202436
the increasing recognition of rickettsial pathogens in dogs and people.dogs and people are exposed to and susceptible to infection by many of the same tick-borne bacterial pathogens in the order rickettsiales, including anaplasma phagocytophilum, ehrlichia canis, e. chaffeensis, e. ewingii, rickettsia rickettsii, r. conorii, and other spotted fever group rickettsiae. recent findings include descriptions of novel ehrlichia and rickettsia species, recognition of the occurrence and clinical significance of co-infection, and increasing awareness of rhipicephalus sangui ...201020207197
an interview with robert s. lane, ph.d. interviewed by vicki glaser.dr. robert lane received a b.a. degree in psychology from the university of california at berkeley (ucb), an m.a. degree in biology at san francisco state college, and a ph.d. in entomology at ucb. while employed as a california state public health biologist he began his long-standing studies of the biology of ticks and the ecology and epidemiology of tick-borne disease agents. in 1984, dr. lane joined the faculty of ucb as a medical entomologist, a position he has held until the present. the di ...201020350056
bacterial diversity in amblyomma americanum (acari: ixodidae) with a focus on members of the genus rickettsia.the lone star tick, amblyomma americanum (acari: ixodidae), is commonly reported from people and animals throughout the eastern u.s. and is associated with transmission of a number of emerging diseases. to better define the microbial communities within lone star ticks, 16s rrna gene based analysis using bacteria-wide primers, followed by sequencing of individual clones (n = 449) was used to identify the most common bacterial operational taxonomic units (otus) present within colony-reared and wil ...201020380308
rickettsia hoogstraalii sp. nov., isolated from hard- and soft-bodied ticks.a novel spotted fever group rickettsia was found in haemaphysalis sulcata ticks collected from sheep and goats in croatia in 2006. at the same time, a genetically identical organism was co-isolated with the embryonic cell line cce3 obtained from the soft tick carios capensis in georgia, usa. in this study, further phenotypic and genotypic characteristics of the novel rickettsial strain present in h. sulcata ticks were investigated. based on the cultivation of bacteria in mosquito and vero cell c ...201019666817
rickettsia sca2 is a bacterial formin-like mediator of actin-based motility.diverse intracellular pathogens subvert the host actin-polymerization machinery to drive movement within and between cells during infection. rickettsia in the spotted fever group (sfg) are gram-negative, obligate intracellular bacterial pathogens that undergo actin-based motility and assemble distinctive 'comet tails' that consist of long, unbranched actin filaments. despite this distinct organization, it was proposed that actin in rickettsia comet tails is nucleated by the host arp2/3 complex a ...201020972427
rickettsial infections of fleas collected from small mammals on four islands in indonesia.ectoparasites were sampled from small mammals collected in west java, west sumatra, north sulawesi, and east kalimantan, indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the rickettsaceae family. during eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 rodentia; 123 soricomorpha; two carnivora; three scandentia). two species of fleas were collected: xenopsylla cheopis (n = 204) and nosopsyllus ...201021175069
brazilian spotted fever in cart horses in a non-endemic area in southern brazil.brazilian spotted fever (bsf) is an often fatal zoonosis caused by the obligate intracellular bacterium rickettsia rickettsii. the disease is generally transmitted to humans by amblyomma spp. ticks. serological evidence of past infection by r. rickettsii has been reported in horses, but the pathogenicity of r. rickettsii in horses remains unknown. cart horses are still widely used in urban and urban fringe areas in brazil, and these animals may constitute suitable sentinels for bsf human in thes ...201020624353
epidemiology of spotted fever group and typhus group rickettsial infection in the amazon basin of peru.a seroprevalence study for igg antibodies against spotted fever group (sfgr) and typhus group (tgr) rickettsia among humans and domestic pets was conducted in the city of iquitos, located in the amazon basin of peru. of 1,195 human sera analyzed, 521 (43.6%) and 123 (10.3%) were positive for sfgr and tgr antibodies, respectively. district of residence and participant age were associated with antibody positivity for both groups, whereas rodent sightings in the home were associated with tgr antibo ...201020348519
the expanding spectrum of eschar-associated rickettsioses in the united states.until recently, rickettsia rickettsii was the only substantiated cause of tick-borne spotted fever group (sfg) rickettsiosis in humans in the united states. rickettsia parkeri, originally thought to be nonpathogenic in humans, was recently proved to be another cause of tick-borne sfg rickettsiosis.201020404224
high prevalence of rickettsia gravesii sp. nov. in amblyomma triguttatum collected from feral pigs.a survey of ectoparasites on feral pigs identified two commonly occurring ixodid tick species; amblyomma triguttatum triguttatum and ixodes australiensis. molecular screening of a. t. triguttatum and i. australiensis for the presence of rickettsia species detected the presence of rickettsiae belonging to the spotted fever group (sfg) in 78.4% of screened a. t. triguttatum. none of the screened i. australiensis were positive for rickettsiae. sequence analysis of the glta and ompa loci of positive ...201020488632
health risks in travelers to south africa: the geosentinel experience and implications for the 2010 fifa world cup.using the geosentinel database, an analysis of ill patients returning from throughout sub-saharan africa over a 13-year period was performed. systemic febrile illness, dermatologic, and acute diarrheal illness were the most common syndromic groupings, whereas spotted fever group rickettsiosis was the most common individual diagnosis for travelers to south africa. in contrast to the rest of sub-saharan africa, only six cases of malaria were documented in south africa travelers. vaccine-preventabl ...201020519590
contribution of rickettsioses in sri lankan patients with fever who responded to empirical doxycycline treatment.twenty-eight febrile sri lankan patients with undiagnosed fever for 7 days after hospital admission, who responded to empirical treatment with doxycycline, were retrospectively investigated using microimmunofluorescence assay to verify whether they had rickettsial infection. eleven (39%) patients were confirmed as having spotted fever group rickettsioses and 10 (36%) as having orientia tsutsugamushi. seven were negative for all tests. this suggests that greater use of doxycycline appears justifi ...201019931108
prevalence of selected vector-borne organisms and identification of bartonella species dna in north american river otters (lontra canadensis).trapper-killed north american river otters (lontra canadensis) in north carolina, usa, were screened for multiple vector-borne bacteria known to be pathogenic to mammals. blood was collected from 30 carcasses in 2006, from 35 in 2007, and from one live otter in 2008. samples were screened using conventional polymerase chain reaction (pcr) tests for dna from bartonella spp., ehrlichia spp., and spotted fever group rickettsia spp. all samples were negative for rickettsia spp. twelve of 30 samples ...201020688703
dermacentor marginatus and ixodes ricinus ticks versus l929 and vero cell lines in rickettsia slovaca life cycle evaluated by quantitative real time pcr.ticks transmit many different pathogens to animals, humans and their pets. rickettsia slovaca, as a member of the spotted-fever-group rickettsiae is an agent of the human disease tick-borne lymphadenopathy (tibola), also called dermacentor-borne necrosis erythema and lymphadenopathy (debonel), which occurs from the mediterranean to central europe, transmitted by dermacentor reticulatus and dermacentor marginatus (acari: ixodidae). in this study, quantitative real time pcr was used to characteriz ...201019779862
detection of "candidatus rickettsia sp. strain argentina"and rickettsia bellii in amblyomma ticks (acari: ixodidae) from northern argentina.ixodid ticks were collected from vegetation and from humans, wild and domestic mammals in a rural area in the semi-arid argentine chaco in late spring 2006 to evaluate their potential role as vectors of spotted fever group (sfg) rickettsiae. a total of 233 adult ticks, identified as amblyomma parvum, amblyomma tigrinum and amblyomma pseudoconcolor, was examined for rickettsia spp. we identified an sfg rickettsia of unknown pathogenicity, "candidatus rickettsia sp. strain argentina", in a. parvum ...201020186466
isolation of rickettsia parkeri and identification of a novel spotted fever group rickettsia sp. from gulf coast ticks (amblyomma maculatum) in the united states.until recently, amblyomma maculatum (the gulf coast tick) had garnered little attention compared to other species of human-biting ticks in the united states. a. maculatum is now recognized as the principal vector of rickettsia parkeri, a pathogenic spotted fever group rickettsia (sfgr) that causes an eschar-associated illness in humans that resembles rocky mountain spotted fever. a novel sfgr, distinct from other recognized rickettsia spp., has also been detected recently in a. maculatum specime ...201020208020
questing ticks in suburban forest are infected by at least six tick-borne pathogens.abstract the role of ixodes ricinus ticks in the transmission of pathogens of public health importance such as borrelia burgdorferi s.l. is widely recognized and is suspected in several emerging vector-borne pathogens in europe. here, we assess prevalence rates of several endemic and emerging zoonotic pathogens in tick populations in an area of high human population density in france, to contribute to a risk assessment for potential transmission to humans. pathogen prevalence rates were evaluate ...201021158500
rickettsia africae in amblyomma variegatum and domestic ruminants on eight caribbean islands.we used pcrs with omp a primers to determine if spotted fever group rickettsiae occurred in amblyomma variegatum from 6 caribbean islands. positive amplicons were obtained from ticks from the u.s. virgin islands (9/18; 50%), dominica (39/171; 30%), montserrat (2/5; 40%), nevis (17/34; 50%), st. kitts (46/227; 20%), and st. lucia (1/14; 7%). sequences for a convenience sample of reaction products obtained from a. variegatum on st. kitts (7), american virgin islands (4), montserrat (2), and st. lu ...201021158615
rickettsia 364d: a newly recognized cause of eschar-associated illness in california.four spotted fever group rickettsiae (sfgr) are known to infect humans in the united states. a member of the sfgr designated 364d and detected in dermacentor occidentalis ticks has not previously been identified as a human pathogen.201020073993
serosurvey of antibodies against spotted fever group rickettsia spp. in horse farms in northern paraná, brazil.brazilian spotted fever (bsf) is an emerging disease most likely caused by rickettsia rickettsii. the objective of the present study was to estimate the seroprevalence of bsf rickettsia infections in equines from six horse farms located in londrina county, paraná, southern brazil. six owners of horse farms situated in cambé, santa fé, guaraci and londrina municipalities participated in the study. all farms were located in areas where bsf has not been reported. a total of 273 horses were sampled ...201021184706
survey for tick-borne zoonoses in the state of espirito santo, southeastern brazil.blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of espirito santo, brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were ...201020595502
the occurrence of spotted fever rickettsioses and other tick-borne infections in forest workers in poland.abstract the presence of antibodies to rickettsia conorii, r. helvetica, r. felis, r. slovaca, r. sibirica, and r. massiliae in sera of 129 forest workers from northeastern and southern poland was assayed by indirect immunofluorescence. previous environmental studies revealed presence of spotted fever group (sfg) rickettsiae in ticks collected from these areas. additionally, the workers were examinated for the presence of antibodies specific to other tick-borne bacteria: anaplasma phagocytophilu ...201021083370
first detection of spotted fever group rickettsiae in ixodes ricinus and dermacentor reticulatus ticks in the uk.a preliminary study was conducted to determine the presence of spotted fever rickettsiae in two species of british tick (ixodes ricinus and dermacentor reticulatus). the 16s rrna gene of rickettsia spp. was detected in 39/401 (9·7%) of ticks tested, including 22/338 (6·5%) i. ricinus and 17/63 (27%) d. reticulatus. some positive i. ricinus samples showed 100% homology with rickettsia helvetica (10/22), and most positive d. reticulatus showed 100% homology with r. raoultii (13/17). five other ric ...201021087541
high incidence of rickettsiosis correlated to prevalence of rickettsia japonica among haemaphysalis longicornis tick.endemic spotted fever group rickettsiosis was reported in shimane prefecture, japan. from an analysis of 14 clinical cases found in the endemic area, the infectious agent of spotted fever group rickettsiosis was identified as rickettsia japonica. in this study, we also found that rickettsia japonica was highly infected with the vector tick, haemaphysalis longicornis, in the endemic area. these findings suggest that the high incidence of rickettsiosis in shimane prefecture can be explained by the ...201021139348
first detection of spotted fever group rickettsiae in ticks in serbia.ticks can transmit multiple pathogenic bacteria responsible for diseases in animals and humans such as borrelia burgdorferi sensu lato, anaplasma phagocytophilum, and spotted fever group rickettsia sp. the current study aimed to investigate the presence of rickettsiae in ticks collected from seven localities in serbia. one hundred thirty-one (131) questing ticks belonging to 5 tick species (dermacentor marginatus, dermacentor reticulatus, haemaphysalis punctata, haemaphysalis concinna, and ixode ...201021142961
adherence to and invasion of host cells by spotted fever group rickettsia species.the pathogenic lifecycle of obligate intracellular bacteria presents a superb opportunity to develop understanding of the interaction between the bacteria and host under the pretext that disruption of these processes will likely lead to death of the pathogen and prevention of associated disease. species of the genus rickettsia contain some of the most hazardous of the obligate intracellular bacteria, including rickettsia rickettsii and r. conorii the causative agents of rocky mountain and medite ...201021687751
fatal spotted fever group rickettsiosis due to rickettsia conorii conorii mimicking a hemorrhagic viral fever in a south african traveler in brazil.the authors present a fatal case of spotted fever group rickettsiosis (sfgr) caused by rickettsia conorii conorii mimicking a hemorrhagic viral fever in a south african male on a business trip in brazil. sfgr was confirmed by molecular and immunohistochemical analyses.201021771523
coxiella burnetii and coinfections in ixodes ricinus ticks in central germany.abstract a total of 1000 ixodes ricinus ticks were collected in 2006 and 2007 in a forest region of central germany and investigated for coxiella burnetii. the transposase element is1111 and isocitrate dehydrogenase gene were targets of the real-time polymerase chain reaction. the pathogen was detected in 19 ticks (1.9%), and interestingly, in 10 of these samples, coinfections with borrelia spp., spotted fever group rickettsiae, or babesia spp. were present. our study reports on c. burnetii infe ...201021142964
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