| description of the first reported human case of spotted fever group rickettsiosis in urban bangkok. | described herein is the clinical presentation of a patient from bangkok, with fever, petechial rash, history of a tick bite, and a diagnosis of spotted fever rickettsiosis. | 2007 | 17984348 |
| the typhus-rocky mountain spotted fever group of infections in the eastern and southeastern states. | | 1931 | 18013262 |
| african tick bite fever--papulovesicular exanthem with fever after staying in south africa. | in the wake of expanding international tourism, rickettsioses are increasingly observed also in central europe. african tick bite fever is a recently described, acute febrile illness with characteristic skin lesions. it is caused by rickettsia africae, which is transmitted to humans by ticks of the amblyomma genus. a 60-year-old woman presented with a papulovesic-ular exanthem, fever, and headache after returning from south africa. a purple nodule with central necrosis ("tache noire"or "inoculat ... | 2008 | 18021248 |
| rickettsial diseases in russia. | currently, several rickettsioses are officially being reported in the russian federation. these are epidemic typhus and brill-zinsser disease, both caused by rickettsia prowazekii which has a historic prevalence in russia. nowadays only single sporadic cases of r. prowazekii infection are reported. the last significant outbreak occurred in 1997 in a mental nursing home, where 29 cases were identified. registered morbidity of typhus in russia varies from 0 to 0.01 per thousand for the last decade ... | 2006 | 17114680 |
| real-time multiplex pcr assay for detection and differentiation of rickettsiae and orientiae. | the high incidence of rickettsial diseases in southeast asia necessitates rapid and accurate diagnostic tools for a broad range of rickettsial agents, including orientia tsutsugamushi (scrub typhus) and rickettsia typhi (murine typhus), but also spotted fever group infections, which are increasingly reported. we present an sybr-green-based, real-time multiplex pcr assay for rapid identification and differentiation of scrub typhus group, typhus group and spotted fever group rickettsiae using 47kd ... | 2008 | 18093627 |
| rickettsia amblyommii infecting amblyomma americanum larvae. | polymerase chain reaction analysis of amblyomma americanum adults, nymphs, and larvae from aberdeen proving ground, md (apg), revealed a very high prevalence of a spotted fever group (sfg) rickettsia. restriction fragment length polymorphism (rflp) and sequence analysis identified "rickettsia amblyommii." this organism is not yet described or well studied, and its pathogenicity is unknown; however, investigations of the organism are warranted because of its high prevalence in a. americanum. this ... | 2008 | 18171102 |
| prevalence of seropositivity to spotted fever group rickettsiae and anaplasma phagocytophilum in a large, demographically diverse us sample. | most epidemiologic studies of tick-borne rickettsial diseases in the united states are small and have limited demographic scope, making broader risk assessment difficult. | 2008 | 18171216 |
| rocky mountain spotted fever, colombia. | we investigated 2 fatal cases of rocky mountain spotted fever that occurred in 2003 and 2004 near the same locality in colombia where the disease was first reported in the 1930s. a retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae. | 2007 | 18214179 |
| severe spotted fever group rickettsiosis, australia. | we report 3 cases of spotted fever group rickettsial infection (presumed queensland tick typhus) in residents of northern queensland, australia, who had unusually severe clinical manifestations. complications included renal failure, purpura fulminans, and severe pneumonia. clinical illness caused by rickettsia australis may not be as benign as previously described. | 2007 | 18217560 |
| evaluation of conventional and real-time pcr assays for detection and differentiation of spotted fever group rickettsia in dog blood. | spotted fever group rickettsia is important cause of emerging and re-emerging infectious disease in people and dogs. importantly, dogs can serve as sentinels for disease in people. sensitive and specific diagnostic tests that differentiate among species of infecting rickettsia are needed. the objective of this study was to develop a sensitive and specific pcr that differentiates sfg rickettsia infecting dog blood. conventional and real-time pcr assays were developed using primers that targeted a ... | 2008 | 18226476 |
| serologic and molecular characterization of tickborne pathogens in lions (panthera leo) from the fasano safari park, italy. | lions (panthera leo) are an endangered species threatened by illegal hunting, habitat loss, and infectious diseases. little is known about the tick-borne pathogens that infect lions and could contribute to population declines. the objective of this study was to characterize rickettsia spp., anaplasma phagocytophilum, and coxiella burnetii infections in 10 lions from the fasano safari park in italy by serology, polymerase chain reaction, and sequence analysis. although animals did not show clinic ... | 2007 | 18229868 |
| prevalence of antibodies to rickettsiae in different regions of serbia. | we assayed the presence of antibodies specific for rickettsia typhi, r. akari, and r. conorii in sera of persons from several localities in serbia with different geographic, climatic, and lifestyle characteristics. sera from 140 patients with unclear clinical symptoms and 273 healthy persons were tested for the presence of rickettsiae-specific antibodies by indirect immunofluorescence assay. in this study, for the first time we detected the presence of rickettsiae from the spotted fever group in ... | 2008 | 18240971 |
| co-circulating microorganisms in questing ixodes scapularis nymphs in maryland. | ixodes scapularis can be infected with borrelia burgdorferi, anaplasma phagocytophilum, bartonella spp., babesia microti, and rickettsia spp., including spotted-fever group rickettsia. as all of these microorganisms have been reported in maryland, the potential for these ticks to have concurrent infections exists in this region. to assess the frequency of these complex infections, 348 i. scapularis nymphs collected in 2003 were screened for these microorganisms by pcr with positives being confir ... | 2007 | 18260514 |
| potentially pathogenic spotted fever group rickettsiae present in western australia. | | 2006 | 17121510 |
| rocky mountain spotted fever in argentina. | we describe the first molecular confirmation of rickettsia rickettsii, the cause of rocky mountain spotted fever (rmsf), from a tick vector, amblyomma cajennense, and from a cluster of fatal spotted fever cases in argentina. questing a. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in jujuy province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. dna of r. rickettsii was amplified from a pool ... | 2008 | 18385370 |
| a case of spotted fever group rickettsiosis imported into the united kingdom and treated with ciprofloxacin: a case report. | spotted fever group rickettsioses are an interesting group of infections, which are increasing in incidence worldwide. | 2008 | 18387179 |
| characterization of rickettsial infection in amblyomma americanum (acari: ixodidae) by quantitative real-time polymerase chain reaction. | several species of the spotted fever group rickettsia (sfgr), with considerable variation in vertebrate host pathogenicity, are present in ticks in the united states. in this study, quantitative real-time pcr (qpcr) was used to characterize the growth and the distribution of rickettsia amblyommii in selected tissues (salivary glands, gut, and ovaries) of naturally infected amblyomma americanum (l.) (acari: ixodidae), during bloodmeal acquisition and throughout vertical transmission to eggs and p ... | 2008 | 18402143 |
| spotted fever group rickettsioses in himachal pradesh. | rickettsiae are in many places of the world emerging or reemerging pathogens. the spotted fevers group (sfg) composes a large group of tick- and mite-borne zoonotic infections that are caused by closely related rickettsiae. the sfg rickettsiae of southeast asia are yet to be identified. earlier reports have documented the endemicity of rickettsioses among adults in the himalayan belt but no confirmed case of spotted fever have been reported from this region of india. we present two cases of sfg ... | 2007 | 18405137 |
| [rickettsial spotted fever in the paraná delta. an emerging disease]. | we describe a case of rickettsial spotted fever in the paraná delta region of buenos aires province in argentina. the patient developed an acute febrile syndrome characterized by myalgias, headache, asthenia and moderate odynophagia, followed by a diffuse macular, papular, and purpuric exanthema. the patient had been bitten recently by a tick on the left preauricular region and an erosive papular lesion was evident at the bite site. an indirect immunofluorescence antibody assay identified antibo ... | 2007 | 18422067 |
| molecular detection of spotted fever group rickettsiae in ticks from ethiopia and chad. | dna extracted from 363 ticks collected in ethiopia and 9 ticks collected in chad, africa were screened by pcr to detect dna from spotted fever group rickettsiae. fifteen ticks (4.1%) collected in ethiopia and one tick (11%) collected in chad tested positive when pcr targeting the glta and ompa rickettsial genes was performed. pcr-positive products of the glta and ompa genes were used for dna sequencing. rickettsia africae was detected in 12/118 amblyomma lepidum and in 1/2 a. variegatum. also, 2 ... | 2008 | 18440576 |
| tick-borne diseases in north carolina: is "rickettsia amblyommii" a possible cause of rickettsiosis reported as rocky mountain spotted fever? | cases of rocky mountain spotted fever (rmsf) in north carolina have escalated markedly since 2000. in 2005, we identified a county in the piedmont region with high case numbers of rmsf. we collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (sfgr) might be emerging. amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. in contrast, dermacen ... | 2008 | 18447622 |
| variations of plasmid content in rickettsia felis. | since its first detection, characterization of r. felis has been a matter of debate, mostly due to the contamination of an initial r. felis culture by r. typhi. however, the first stable culture of r. felis allowed its precise phenotypic and genotypic characterization, and demonstrated that this species belonged to the spotted fever group rickettsiae. later, its genome sequence revealed the presence of two forms of the same plasmid, physically confirmed by biological data. in a recent article, g ... | 2008 | 18509454 |
| detection and identification of spotted fever group rickettsiae in dermacentor species from southern california. | dermacentor occidentalis marx and dermacentor variabilis (say) commonly bite humans in california. these dermacentor species may play a role in transmitting spotted fever group (sfg) rickettsiae to humans in many parts of the state where dermacentor andersoni stiles, a known vector for the etiologic agent of rocky mountain spotted fever, rickettsia rickettsii, is absent. however, the specific rickettsial agents present in these ticks and their current prevalence are poorly understood. in total, ... | 2008 | 18533446 |
| a case of murine typhus associated with large vessel infarct of the spleen. | we present a case of rickettsia typhi infection (the causative agent of endemic typhus) associated with an isolated splenic infarction. large vessel infarction is a rare complication of murine typhus, unlike infections caused by rickettsia rickettsii and rickettsia conorii (the spotted fever group rickettsias) which are known to cause hemostatic changes that lead to coagulopathies and thrombotic events. this case adds to the scarce data in the literature on the association between large vessels ... | 2008 | 18552585 |
| survey of the vectorial competence of ticks in an endemic area of spotted fever group rickettsioses in fukui prefecture, japan. | the prevalence of sfgr in ixodid ticks in the mt. arashima-dake area in the northern part of fukui prefecture was surveyed, because of strong suspicions that the first case identified in this prefecture had become infected with r. helvetica in this region. the ticks identified consisted of three genera and six species; i.ovatus, i. persulcatus, i. monospinosus, h. flava, h. japonica and d. taiwanensis. of all 222 ticks collected, only i. monospinosus ticks (8 of 32 examined) were positive for sf ... | 2008 | 18577164 |
| spotted fever group rickettsiae in ticks, morocco. | a total of 370 ticks, encompassing 7 species from 4 genera, were collected during 2002-2006 from domestic animals and vegetation in the taza region of northeastern morocco. rickettsial dna was identified in 101 ticks (27%) by sequencing pcr products of fragments of the citrate synthase and outer membrane protein genes of rickettsia spp. seven rickettsiae of the spotted fever group were identified, including 4 pathogens: r. aeschlimannii in hyalomma marginatum marginatum, r. massiliae in rhipicep ... | 2008 | 18598627 |
| rickettsia raoultii sp. nov., a spotted fever group rickettsia associated with dermacentor ticks in europe and russia. | we describe the characterization of a novel rickettsia species cultivated from dermacentor ticks collected in russia and france, for which we propose the name rickettsia raoultii sp. nov. using multigene sequencing, we demonstrated that five rickettsial isolates from dermacentor silvarum, dermacentor reticulatus, dermacentor marginatus and dermacentor nuttalli ticks were classified within this novel spotted fever rickettsia species. this rickettsia also exhibited a serotype distinct from previou ... | 2008 | 18599708 |
| ricka expression is not sufficient to promote actin-based motility of rickettsia raoultii. | rickettsia raoultii is a novel rickettsia species recently isolated from dermacentor ticks and classified within the spotted fever group (sfg). the inability of r. raoultii to spread within l929 cells suggests that this bacterium is unable to polymerize host cell actin, a property exhibited by all sfg rickettsiae except r. peacocki. this result led us to investigate if ricka, the protein thought to generate actin nucleation, was expressed within this rickettsia species. | 2008 | 18612416 |
| tick-borne zoonotic bacteria in wild and domestic small mammals in northern spain. | the prevalence and diversity of tick-borne zoonotic bacteria (borrelia spp., anaplasma phagocytophilum, coxiella burnetii, and spotted fever group rickettsiae) infecting 253 small mammals captured in the basque country (spain) were assessed using pcr and reverse line blot hybridization. trapping sites were selected around sheep farms (study 1, 2000 to 2002) and recreational parks (study 2, 2003 to 2005). the majority of the studied mammals (162) were wood mice (apodemus sylvaticus), but six othe ... | 2007 | 17693556 |
| detection of spotted fever and typhus group rickettsial infection in wild raccoon dogs (nyctereutes procyonoides koreensis) in chonbuk province, korea. | both the spotted fever and the typhus group rickettsioses are potential emerging arthropod-borne infectious disease complexes in korea. wild raccoon dogs (nyctereutes procyonoides koreensis) sheltered at the korean society for the protection of wild animals, chonbuk branch, korea, were sampled for the presence of spotted fever and typhus group rickettsial pathogens. thirty-six serum samples of wild raccoon dogs were examined by an indirect fluorescent antibody test using type-specific yh strain ... | 2008 | 18634203 |
| genomic comparison of virulent rickettsia rickettsii sheila smith and avirulent rickettsia rickettsii iowa. | rickettsia rickettsii is an obligate intracellular pathogen that is the causative agent of rocky mountain spotted fever. to identify genes involved in the virulence of r. rickettsii, the genome of an avirulent strain, r. rickettsii iowa, was sequenced and compared to the genome of the virulent strain r. rickettsii sheila smith. r. rickettsii iowa is avirulent in a guinea pig model of infection and displays altered plaque morphology with decreased lysis of infected host cells. comparison of the t ... | 2008 | 18025092 |
| spotted fever group rickettsia in brown dog ticks rhipicephalus sanguineus in southwestern spain. | a total of 2,229 adults ticks (1,428 males and 801 females) belonging to the brown dog tick, rhipicephalus sanguineus latreille, 1806, collected from dogs in seville province (andalusia), distributed in 500 lots ranging from one to eight specimens per lot, were examined for the presence of rickettsiae by molecular techniques. specific rickettsiae dna were detected in 90 lots (18%) of ticks tested. sequence analysis of amplicons revealed that r. sanguineus ticks were infected exclusively with ric ... | 2008 | 18340465 |
| western-blot detection of ricka within spotted fever group rickettsiae using a specific monoclonal antibody. | spotted fever group rickettsiae are obligate intracellular pathogens able to manipulate the actin cytoskeleton, thus enabling cell-to-cell spreading during infection. while the ricka protein, which has similarity to the wasp family of arp2/3-complex activators, was described as being responsible for actin-based motility, recent studies demonstrated that another factor, still unidentified, is also involved in this phenomenon. here, using recombinant protein of rickettsia conorii as an antigen, we ... | 2008 | 18657112 |
| [ticks and human tick-borne diseases in africa]. | ticks are obligate hematophagous arthropod parasites that feed on the blood of every class of vertebrates in almost every region of the world. tick bites can transmit bacterial, viral and parasitic diseases to humans. in this review we describe ticks and human tick-borne diseases in africa. the first part of this article presents elements linking the morphology and biology of these acarians as well as various aspects of their taxonomy and phylogeny. the next part of the article describes the mai ... | 2008 | 18630043 |
| isolation and identification of a novel spotted fever group rickettsia, strain ig-1, from ixodes granulatus ticks collected on orchid island (lanyu), taiwan. | a novel species of spotted fever group (sfg) rickettsia, rickettsia spp. ig-1, was identified and isolated from adult ixodes granulatus ticks collected from orchid island (lanyu), an islet located in southeastern taiwan. serum samples collected from the rodent host rattus losea and sfg-positive human serum reacted with ig-1 using an immunofluorescence assay (ifa). pairwise nucleotide sequence analysis of 16s rrna (rrs), glta, ompa, ompb, and sca4 shows that ig-1 belongs to sfg rickettsiae and ha ... | 2008 | 18689633 |
| evidence of multiple zoonotic agents in a wild rodent community in the eastern sierra nevada. | this study aimed to describe the occurrence of yersinia pestis, rickettsia rickettsii, anaplasma phagocytophilum, and ectoparasites in a wild rodent community in the eastern sierra nevada. from may to september 2006, rodents were live-trapped, examined for ectoparasites, and blood was collected. all rodents were serologically tested for antibodies to y. pestis, r. rickettsii, and a. phagocytophilum; in addition, blood samples and ectoparasites were tested by pcr to detect the presence of these z ... | 2008 | 18689664 |
| molecular detection of spotted fever group rickettsia in dermacentor silvarum from a forest area of northeastern china. | in total, 676 dermacentor silvarum olenev (acari: ixodidae) from a forest area of jilin province in northeastern china were examined by polymerase chain reaction for the presence of spotted fever group (sfg) rickettsia. the overall positive rate was 10.7%, with a 95% confidence interval from 8.3 to 13.0%. the sfg rickettsia infection was more prevalent in adults than in nymphs, and in fed ticks obtained from domestic animals than in those collected on vegetation. sequence analysis of the partial ... | 2008 | 18714877 |
| detection of a spotted fever group rickettsia in the tick ixodes tasmani collected from koalas in port macquarie, australia. | four species of rickettsia are recognized as endemic to australia. this study reports the detection of a new spotted fever group rickettsia in the common marsupial tick ixodes tasmani neumann collected from koalas (phascolarctos cinereus) in port macquarie, nsw, australia. based on the results of polymerase chain reaction (pcr) amplification of extracted tick dna with primers targeting the citrate synthase gene (glta) and the outer membrane proteins a and b (ompa. ompb), rickettsiae were detecte ... | 2008 | 18714878 |
| [contribution of all-ussr (russian) center of rickettsioses and collaboration centre of who to the study of rickettsioses of tick-borne spotted fever group]. | the manuscript presents the results of studies of rickettsioses of spotted fever group in the territories of ussr (russia) and chssr (slovakia). authors review data about isolation of strains of rickettsiae of spotted fever group, improvement of isolation techniques, diagnostics and diagnostic preparations. | 2008 | 18756783 |
| prevalence of tick-borne zoonotic bacteria in questing adult ticks from northern spain. | a total of 691 questing adult ixodid ticks of the genera ixodes, haemaphysalis, dermacentor, and rhipicephalus were tested by polymerase chain reaction (pcr) and reverse line blot (rlb) for the presence of anaplasma phagocytophilum, coxiella burnetii, borrelia spp., and spotted fever group (sfg) rickettsiae. ticks were collected by blanket dragging during 2 sampling years (2003-2005) in 10 recreational areas in the basque country (northern spain). adult ticks were collected every month of the ye ... | 2008 | 18759563 |
| functional characterization and novel rickettsiostatic effects of a kunitz-type serine protease inhibitor from the tick dermacentor variabilis. | here we report the novel bacteriostatic function of a five-domain kunitz-type serine protease inhibitor (kpi) from the tick dermacentor variabilis. as ticks feed, they release anticoagulants, anti-inflammatory and immunosuppressive molecules that mediate the formation of the feeding lesion on the mammalian host. a number of kpis have been isolated and characterized from tick salivary gland extracts. interestingly, we observe little d. variabilis kpi gene expression in the salivary gland and abun ... | 2008 | 18779339 |
| prevalence of spotted fever group rickettsiae in ixodes ricinus (acari: ixodidae) in southern germany. | host-seeking ixodes ricinus (l.) (acari: ixodidae) ticks were collected systematically, from may to september 2006, at selected sites in southern germany, including a large city park in munich. polymerase chain reactions for amplification of genes of the rickettsial citrate synthase (glta), the outer membrane proteins a and b (ompa and ompb), and the 16s rdna were used to investigate 2,861 specimens (adults and nymphs). glta sequences of spotted fever group rickettsiae were detected in 151 of al ... | 2008 | 18826040 |
| geographic variation in risk factors for sfg rickettsial and leptospiral exposure in colombia. | in order to characterize the patterns of human exposure to spotted fever group (sfg) rickettsial and leptospiral infection, igg surveys were conducted on 642 residents of ten different areas of the rural district of necoclí, colombia. areas were selected based on forest cover and human settlement pattern, and individual risk factors were elucidated through multivariate logistic models, controlling for variance clustering within communities. overall, prevalence of high antibody titers indicating ... | 2009 | 18973451 |
| rickettsia conorii transcriptional response within inoculation eschar. | rickettsia conorii, the causative agent of the mediterranean spotted fever, is transmitted to humans by the bite of infected ticks rhipicephalus sanguineus. the skin thus constitutes an important barrier for the entry and propagation of r. conorii. given this, analysis of the survival strategies used by the bacterium within infected skin is critical for our understanding of rickettsiosis. | 2008 | 18997861 |
| louse- and flea-borne rickettsioses: biological and genomic analyses. | in contrast to 15 or more validated and/or proposed tick-borne spotted fever group species, only three named medically important rickettsial species are associated with insects. these insect-borne rickettsiae are comprised of two highly pathogenic species, rickettsia prowazekii (the agent of epidemic typhus) and r. typhi (the agent of murine typhus), as well as r. felis, a species with unconfirmed pathogenicity. rickettsial association with obligate hematophagous insects such as the human body l ... | 2009 | 19036234 |
| 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. | five strains of spotted fever group (sfg) rickettsiae previously isolated from human clinical cases and from the tick haemaphysalis leporispalustris were used for molecular characterization in this study to establish their genetic relationship compared with the prototype rickettsia rickettsii strain sheila smith. samples were tested by polymerase chain reaction (pcr) targeting the rickettsial genes gtla, ompa, and ompb. pcr products of the latter two genes were dna sequenced and compared with av ... | 2008 | 19052300 |
| serum cardiac troponin i concentration in dogs with ehrlichiosis. | ehrlichiosis is a multisystemic disease with the potential to cause cardiomyocyte injury in naturally infected dogs. | 2008 | 18638021 |
| characterization of rickettsia rickettsii in a case of fatal brazilian spotted fever in the city of rio de janeiro, brazil. | a lethal case of brazilian spotted fever (bsf) is presented. clinical features were initially of gastrointestinal involvement and evolved with progression to septic shock, meningoencephalitis and death on the 6th day of illness. indirect immunofluorescence assay (ifa) for spotted fever group rickettsia (sfgr) was non-reactive. diagnosis was confirmed by the polymerase chain reaction (pcr) and the nucleotide sequencing of a fragment of the ompa gene showed 100% homology to rickettsia rickettsii. ... | 2008 | 18641853 |
| [detection of co-infection with lyme spirochetes and spotted fever group rickettsiae in a group of haemaphysalis longicornis]. | the present study was conducted to investigate the infection of lyme disease, spotted fever, ehrlichiosis (anaplasmosisin) in wild animals and ticks in the mountain areas of zhejiang province. | 2008 | 19173967 |
| rickettsia phylogenomics: unwinding the intricacies of obligate intracellular life. | completed genome sequences are rapidly increasing for rickettsia, obligate intracellular alpha-proteobacteria responsible for various human diseases, including epidemic typhus and rocky mountain spotted fever. in light of phylogeny, the establishment of orthologous groups (ogs) of open reading frames (orfs) will distinguish the core rickettsial genes and other group specific genes (class 1 ogs or c1ogs) from those distributed indiscriminately throughout the rickettsial tree (class 2 og or c2ogs) ... | 2008 | 19194535 |
| rickettsia spp. in ticks, poland. | ticks are recognized as the main vectors and reservoirs of spotted fever group rickettsiae. we searched for the most prevalent rickettsia spp. in poland and found r. slovaca and r. helvetica bacteria in ticks in southern and central poland; r. raoulti was found in ticks in all parts of poland. | 2009 | 19239772 |
| molecular identification of spotted fever group rickettsiae in ticks collected in central china. | | 2009 | 19298396 |
| [prevalence of tick-borne encephalitis virus and rickettsiae in ticks of the district burgenland, austria]. | large areas of the central european country austria are known to be endemic for tick-borne encephalitis virus (tbev). however, so far only limited data are available for the prevalence, distribution and species composition of rickettsiae of the spotted fever group in austria. in the present study 306 ticks were collected in summer 2007. location of sampling was neudörfl, a known tbev endemic area in the district of burgenland in eastern austria. 286 ticks belonged to the species ixodes ricinus a ... | 2008 | 19066772 |
| molecular investigations of rickettsia helvetica infection in dogs, foxes, humans, and ixodes ticks. | rickettsia helvetica, a tick-borne member of the spotted-fever-group rickettsiae, is a suspected pathogen in humans; however, its role in animals is unknown. the aims of this study were to establish a r. helvetica-specific real-time taqman pcr assay and apply it to the analysis of tick vectors (to determine potential exposure risk) and blood samples from canidae and humans (to determine prevalence of infection). the newly designed 23s rrna gene assay for r. helvetica was more sensitive than a pu ... | 2009 | 19329665 |
| spotted fever group rickettsia sp. closely related to rickettsia japonica, thailand. | | 2009 | 19331747 |
| the relationship between spotted fever group rickettsiae and ixodid ticks. | spotted fever group rickettsiae are predominantly transmitted by ticks. rickettsiae have developed many strategies to adapt to different environmental conditions, including those within their arthropod vectors and vertebrate hosts. the tick-rickettsiae relationship has been a point of interest for many researchers, with most studies concentrating on the role of ticks as vectors. unfortunately, less attention has been directed towards the relationship of rickettsiae with tick cells, tissues, and ... | 2009 | 19358804 |
| evaluation of pcr-based assay in human serum samples for diagnosis of fatal cases of spotted fever group rickettsiosis. | | 2009 | 19392899 |
| detection of spotted fever group rickettsiae and family anaplasmataceae in ixodes ricinus ticks from republic of moldova and eastern ukraine. | | 2009 | 19416287 |
| a highly sensitive quantitative real-time pcr assay based on the groel gene of contemporary thai strains of orientia tsutsugamushi. | partial nucleotide sequences (459 bp) of the groel gene (encoding the 60-kda heat shock protein, hsp60) from 23 contemporary isolates of orientia tsutsugamushi isolated from patients with acute scrub typhus in thailand were compared with 16 reference strain sequences to evaluate the potential of groel as a conserved and representative target for molecular diagnostics.. overall nucleotide identity within all available o. tsutsugamushi isolates (n = 39) was 98.8% (range: 95.0-100), reflecting a hi ... | 2009 | 19416296 |
| occurrence of rickettsia felis in dog and cat fleas (ctenocephalides felis) from italy. | abstract : rickettsia felis is an obligate intracellular bacterium belonging to the spotted fever group, suspected to cause a murine typhus-like illness in humans, with a cosmopolitan distribution. this study was designed to estimate presence and occurrence of this pathogen in fleas collected from dogs and cats in different areas of italy. two species of fleas were identified, ctenocephalides felis (80.3%) and ctenocephalides canis (19.7%).overall, 320 fleas (257 c. felis and 63 c. canis) collec ... | 2009 | 19426447 |
| molecular survey for spotted fever group rickettsiae in ticks from morocco. | | 2009 | 19456813 |
| 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 ... | 2010 | 19469667 |
| spotted fever group rickettsia in ticks from southeastern spain natural parks. | during an 8-years study, we collected from vegetation or domestic and wild mammals 1246 ticks (624 males, 511 females and 111 nymphs) belonging to 13 species in jaen province (andalusia) and we analyzed these ticks by pcr and sequencing for the presence of rickettsiae. specific rickettsiae dna was detected in 243 (19.5%) of the ticks tested. sequence analysis of amplicons of glta, ompa and ompb genes revealed that ixodes ricinus were infected with r. monacensis, including strain irs3, and r. hel ... | 2008 | 18677442 |
| mitochondrial porin vdac 1 seems to be functional in rickettsial cells. | we have recently shown that rickettsia prowazekii (typhus group rickettsiae) cells incorporate human mitochondrial porin vdac1. here, i report on the import of porin by rickettsiae of spotted fever group. it was shown that rickettsial cells of heavy band of renografin density gradient, known as permeabilized rickettsiae, contain much more vdac 1 compared to the cells of light band, that is, non-permeabilized rickettsiae. these data hint at a functionality of mitochondrial porin in rickettsial ce ... | 2009 | 19538262 |
| characterization of rickettsial diseases in a hospital-based population in central tunisia. | in tunisia, 2 rickettsial groups, spotted fever group and typhus group, have been described since the beginning of the 20th century. mediterranean spotted fever (msf), also known as boutonneuse fever, caused by rickettsia conorii and transmitted by the dog tick rhipicephalus sanguineus, is the most frequent rickettsial infection observed. its seroprevalence in our region is 9% among blood donors and 23% in hospitalized febrile patients. typhus group rickettsioses, caused by r. typhi and r. prowa ... | 2009 | 19538277 |
| spotted fever group rickettsioses documented in morocco. | | 2009 | 19548987 |
| cd4+ cd25+ foxp3- t-regulatory cells produce both gamma interferon and interleukin-10 during acute severe murine spotted fever rickettsiosis. | spotted fever group rickettsiae cause life-threatening human infections worldwide. until now, the immune regulatory mechanisms involved in fatal rickettsial infection have been unknown. c3h/hen mice infected with 3 x 10(5) pfu of rickettsia conorii developed an acute progressive disease, and all mice succumbed to this infection. a sublethal infection induced protective immunity, and mice survived. compared to splenic t cells from sublethally infected mice, splenic t cells from lethally infected ... | 2009 | 19564386 |
| detection and identification of rickettsial agents in ticks from domestic mammals in eastern panama. | several outbreaks of rocky mountain spotted fever have occurred in recent years in colombian communities close to the border with panama. however, little is known about rickettsiae and rickettsial diseases in eastern panamanian provinces, the darien province and the kuna yala, located north of the endemic area in colombia. in 2007, 289 ticks were collected in several towns from dogs, horses, mules, cows, and pigs. dna was extracted from 124 dermacentor nitens, 64 rhipicephalus sanguineus, 43 amb ... | 2009 | 19645289 |
| evidence for the presence of francisella and spotted fever group rickettsia dna in the tick amblyomma fimbriatum (acari: ixodidae), northern territory, australia. | ticks (n = 252) were collected from five wild-caught reptile species during routine trapping in the djukbinj national park and fogg dam reserve, northern territory, australia. pooling of ticks (one to four ticks per pool), according to sex or host animal, resulted in 187 samples used for screening for the presence of rickettsia species via molecular methods. rickettsia dna was detected via the amplification of the glta, ompa, and ompb genes in 57 (34%) of the 187 tick samples, all of which conta ... | 2009 | 19645299 |
| 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 ... | 2010 | 19666817 |
| identification of spotted fever group rickettsia species by polymerase chain reaction-restriction fragment length polymorphism analysis of the sca4 gene. | dna samples from four rickettsial species in japan--r. japonica aoki, r. asiatica io-1, r. helvetica ip-1, and rickettsia tamurae at-1--were analyzed by polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) in which a portion of the sca4 gene was amplified and restriction digested with the mspi enzyme. each spotted fever group rickettsial species exhibited unique restriction profiles after mspi digestion. to examine the possibility of applying pcr-rflp analysis to field s ... | 2009 | 19485769 |
| evaluation of serological tests for the diagnosis of rickettsiosis in denmark. | two commercially available immunofluorescence assays (ifa) were compared using historical sera evaluated for rickettsial antibodies by the weil-felix test. an ifa test produced by focus diagnostics prepared with rickettsia rickettsii and r. typhi antigens was compared with a custom made kit from fuller laboratories with r. rickettsii, r. typhi, r. conorii and r. helvetica as antigens. the serum panel used for the comparison included weil-felix-positive and -negative samples. cross-reactions were ... | 2009 | 19162092 |
| the sca2 autotransporter protein from rickettsia conorii is sufficient to mediate adherence to and invasion of cultured mammalian cells. | obligate intracellular bacteria of the genus rickettsia must adhere to and invade the host endothelium in order to establish an infection. these processes require the interaction of rickettsial surface proteins with mammalian host cell receptors. a previous bioinformatic analysis of sequenced rickettsial species identified a family of at least 17 predicted "surface cell antigen" (sca) genes whose products resemble autotransporter proteins. two members of this family, rompa and rompb of spotted f ... | 2009 | 19805531 |
| african tick bite fever in a taiwanese traveler returning from south africa: molecular and serologic studies. | we report the first imported case of african tick bite fever (atbf) in a patient from taiwan who returned from a 10-day trip to south africa. diagnosis was confirmed by polymerase chain reaction (pcr) from eschar biopsies. portions of rickettsial ompa (491 bp) and ompb (273 bp) genes were amplified and subsequent sequencing of pcr product showed its 100% identity with r. africae. microimmunofluorescence (mif) assay of patient's serum on days 14 and 46 after the onset of illness revealed igg sero ... | 2009 | 19861602 |
| serologic survey for rickettsiosis in bats from são paulo city, brazil. | blood serum samples were collected from 451 bats captured within the são paulo city from april 2007 to november 2008, and individually tested by indirect immunofluorescence assay against antigens derived from five rickettsia species reported to occur in brazil: the spotted fever group (sfg) species r. rickettsii, r. parkeri, r. amblyommii, r. rhipicephali, and the ancestral group species r. bellii. for this purpose, an anti-bat immunoglobulin g was produced and used in the present study. overall ... | 2010 | 19877815 |
| spotted fever rickettsiosis infection in a traveler from sri lanka. | a case is reported of travel-acquired tick-borne spotted fever rickettsiosis from sri lanka. little is known about rickettsial disease in sri lanka and this case may be the first documented instance of travel-acquired spotted fever group rickettsiosis from that origin. | 2009 | 19930388 |
| 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 ... | 2010 | 19931108 |
| detection of a hepatozoon and spotted fever group rickettsia species in the common marsupial tick (ixodes tasmani) collected from wild tasmanian devils (sarcophilus harrisii), tasmania. | tasmanian devils are the largest extant marsupial carnivores, confined to the australian island state of tasmania. the iconic marsupial has dramatically declined in number since the discovery of devil facial tumor disease in 1996 and efforts are being made to uncover vital information to assist in the long-term survival of the species. ticks are the main vectors of arthropod-borne disease in animals, raising the question of whether tasmanian devils may be host to arthropods capable of harboring ... | 2009 | 19303711 |
| 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 ... | 2010 | 20020814 |
| 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 ... | 2011 | 20042069 |
| 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 ... | 2010 | 19779862 |
| 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. | 2010 | 20073993 |
| mediterranean spotted fever, a diagnostic challenge in travellers. | mediterranean spotted fever or boutonneuse fever is caused by rickettsia conorii and transmitted by the brown dog tick. the commonest symptoms are pyrexia, a maculopapular rash, lymphadenopathies and an inoculation eschar. increasingly, it is recognised as a cause of serious illness in southern europe. rickettsial infections of the spotted fever group are rarely reported in belgium. we report the case of a 20-year-old traveller returning from morocco who presented with fever and a markedly swoll ... | 2009 | 20101874 |
| 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. | 2010 | 20102497 |
| 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. | 2010 | 20148824 |
| 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 ... | 2010 | 20176791 |
| 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 ... | 2010 | 20186466 |
| 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 ... | 2010 | 20194597 |
| 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. | 2010 | 20202426 |
| 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. | 2010 | 20202436 |
| tick-borne agents in rodents, china, 2004-2006. | a total of 705 rodents from 6 provinces and autonomous regions of mainland people's republic of china were tested by pcrs for tick-borne agents (anaplasma phagocytophilum, borrelia burgdorferi sensu lato, spotted fever group rickettsiae, and francisella tularensis). infection rates were 5.5%, 6.7%, 9.1% and 5.0%, respectively. eighteen (2.6%) rodents of 10 species were positive for 2 or 3 agents. sequence analysis of pcr products confirmed the presence and genotypes of detected agents. these fin ... | 2009 | 19961668 |
| 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 ... | 2010 | 20208020 |
| [detection of tick and tick-borne pathogen in some ports of inner mongolia]. | to investigate the distribution, composition and situation of natural infection pathogen of tick species in the main ports of inner mongolia. | 2009 | 19731529 |
| 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 ... | 2011 | 20331680 |
| 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 ... | 2010 | 20348519 |
| 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 ... | 2010 | 20207197 |
| 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 ... | 2010 | 20380308 |
| determination of rickettsial and antinuclear antibodies in danish patients with sarcoidosis. | rickettsia helvetica has been proposed as an aetiological agent in sarcoidosis. | 2008 | 20298335 |
| 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 ... | 2010 | 20426684 |
| 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 ... | 2010 | 20453131 |