| line blot and western blot immunoassays for diagnosis of mediterranean spotted fever. | the line blot, a new immunoassay in which antigens are placed on nitrocellulose as narrow lines, was evaluated for its sensitivity and specificity relative to the microimmunofluorescence assay for the diagnosis of mediterranean spotted fever (msf). the line blot assay was only slightly less sensitive and less specific than the microimmunofluorescence assay for detection of immunoglobulin m (igm) or igg in 100 serum specimens from 42 patients with msf. no line blot reactions were observed among 5 ... | 1989 | 2506223 |
| epidemiology of rocky mountain spotted fever in ohio, 1981: serologic evaluation of canines and rickettsial isolation from ticks associated with human case exposure sites. | a survey for the prevalence of rocky mountain spotted fever (rmsf) antibodies in dogs associated with confirmed human cases in ohio was conducted during 1981. twelve of 14 confirmed cases (85%) had a history of dog association prior to onset of rmsf. a total of 29 dogs were included in the study, with 16 dogs providing serum samples for antibody testing and the remainder providing tick samples. serum samples tested by indirect microimmunofluorescence techniques revealed 12/16 dogs (75%) to be se ... | 1984 | 6435461 |
| ancestral divergence of rickettsia bellii from the spotted fever and typhus groups of rickettsia and antiquity of the genus rickettsia. | the eubacterial genus rickettsia belongs to the alpha subgroup of the phylum proteobacteria. this genus is usually divided into three biotypes on the basis of vector host and antigenic cross-reactivity characteristics. however, the species rickettsia bellii does not fit into this classification scheme; this organism has characteristics common to both the spotted fever group and the typhus group biotypes and also exhibits some unique features. sequences of the 16s rrna and 23s rrna genes from ric ... | 1994 | 7981106 |
| a new rickettsia from a herbivorous insect, the pea aphid acyrthosiphon pisum (harris). | an undescribed, maternally heritable, rod-shaped bacterium (or "tertiary symbiont") was detected by microscopy in hemolymph of about half (59/122) of pea aphid [acyrthosiphon pisum (harris)] clones collected from widely separated locations in california. on the basis of molecular phylogenetic analysis of 16s rdna sequences, the bacterium was clearly placed among other rickettsia in the alpha-subgroup of proteobacteria, close to rickettsia bellii-a rickettsia found in ticks. a pcr assay was devel ... | 1996 | 8662184 |
| citrate synthase gene comparison, a new tool for phylogenetic analysis, and its application for the rickettsiae. | using pcr and an automated laser fluorescent dna sequencer, we amplified and sequenced a 1,234-bp fragment of the citrate synthase-encoding gene (glta) of 28 bacteria belonging to the genus rickettsia. comparative sequence analysis showed that most of the spotted fever group (sfg) rickettsiae belonged to one of two subgroups. the first subgroup included rickettsia massiliae, strain bar 29, rickettsia rhipicephali, "rickettsia aeschlimanni," and rickettsia montana, which have been isolated only f ... | 1997 | 9103608 |
| taxonomic relationships among spotted fever group rickettsiae as revealed by antigenic analysis with monoclonal antibodies. | the spotted fever group (sfg) is made up of more than 20 different rickettsial species and strains. study of the taxonomic relationships among the group has been attempted by phenotypic, genotypic, and phylogenetic analyses. in this study, we determined taxonomic relationships among the sfg rickettsiae by comparative analysis of immunogenic epitopes reactive against a panel of monoclonal antibodies. a total of 98 monoclonal antibodies, which were directed against epitopes on the major immunodomi ... | 1998 | 9542904 |
| phylogenetic analysis of members of the genus rickettsia using the gene encoding the outer-membrane protein rompb (ompb). | to confirm the phylogenetic analysis previously inferred by comparison of the citrate synthase and rompa gene sequences (gita and ompa, respectively), the rompb gene (ompb) of 24 strains of the genus rickettsia was amplified and sequenced. rompb is an outer-membrane protein of high molecular mass, the presence of which can be demonstrated in most rickettsiae by immunological cross-reactivity in western blots. no pcr amplification was obtained with rickettsia bellii or rickettsia canadensis. for ... | 2000 | 10939649 |
| rickettsia associated with male-killing in a buprestid beetle. | many populations of the buprestid leaf-mining beetle, brachys tessellatus, from central south carolina, usa, show highly skewed sex ratios, ranging from 1.3 to 6.0 females per male. we have identified a rickettsia bacterium that is associated with sex ratio distortion (srd) and selective killing of male embryos in b. tessellatus. molecular assays of infection by this bacterium are highly associated with srd within families, and treatment with an antibiotic (tetracycline) increases the number of ... | 2001 | 11520350 |
| rickettsia species infecting amblyomma cooperi ticks from an area in the state of são paulo, brazil, where brazilian spotted fever is endemic. | owing to the potential role of the tick amblyomma cooperi in the enzootic cycle of rickettsia rickettsii, the etiologic agent of brazilian spotted fever (bsf), this study evaluated infection by rickettsia species in a. cooperi ticks collected from an area in brazil where bsf is endemic. among a total of 40 a. cooperi adult ticks collected in an area of bsf endemicity in the state of são paulo, pcr analysis detected dna of rickettsia bellii in 16 ticks (40%), and 3 other ticks (7.5%) were positiv ... | 2004 | 14715737 |
| rickettsia bellii and rickettsia amblyommii in amblyomma ticks from the state of rondônia, western amazon, brazil. | this study evaluates the rickettsial presence in amblyomma ticks from eight areas of the amazon forest in rondônia, brazil. the following tick species (number in parentheses) were examined: amblyomma ovale koch (121), amblyomma cajennense (f.) (41), amblyomma naponense (packard) (36), amblyomma scalpturatum neumann (35), amblyomma oblongoguttatum koch (30), amblyomma incisum neumann (27), amblyomma rotundatum koch (16), amblyomma coelebs neumann (10), and amblyomma humerale koch (6). ticks were ... | 2004 | 15605647 |
| the first finding of a rickettsia bacterium associated with parthenogenesis induction among insects. | the larval endoparasitoid, neochrysocharis formosa (westwood), is an important natural enemy of the leafminer liriomyza trifolii (burgess) in japan. the thelytokous strain of n. formosa mostly produces female progeny. male progeny were produced by females treated with tetracycline, suggesting that microorganisms induce thelytoky in n. formosa. the result of nucleotide sequencing of the 16s rrna gene indicated that the parasitoid is infected with a rickettsia bacterium, which appears to be causat ... | 2006 | 16450063 |
| [rickettsiae detection in amblyomma ticks (acari: ixodidae) collected in the urban area of campinas city, sp]. | the city of campinas is located in an endemic area for brazilian spotted fever in são paulo state, where several cases have recently occurred. capybaras have been associated with the cycle of this disease, for they present positive serology and serve as host for ticks of the genus amblyomma, the main vectors of brazilian spotted fever. ticks were collected both from capybaras and from the vegetation in the city park lago do café, located in the urban area of campinas city, sp, a site associated ... | 2006 | 16501770 |
| genome sequence of rickettsia bellii illuminates the role of amoebae in gene exchanges between intracellular pathogens. | the recently sequenced rickettsia felis genome revealed an unexpected plasmid carrying several genes usually associated with dna transfer, suggesting that ancestral rickettsiae might have been endowed with a conjugation apparatus. here we present the genome sequence of rickettsia bellii, the earliest diverging species of known rickettsiae. the 1,552,076 base pair-long chromosome does not exhibit the colinearity observed between other rickettsia genomes, and encodes a complete set of putative con ... | 2006 | 16703114 |
| ultrastructural and molecular identification of a new rickettsia endosymbiont in the springtail onychiurus sinensis (hexapoda, collembola). | in this paper we provide microscopic and molecular evidence for the presence of an endosymbiontic bacterium in male and female gonads of the soil arthropod onychiurus sinensis. the sequence of the gene encoding for the 16s rrna shows that the bacterium is a member of the genus rickettsia, and some anomalies presumably associated with the presence of these microorganisms have been detected. although the rickettsia found in o. sinensis has the smallest genetic divergence with rickettsia bellii, th ... | 2006 | 16934288 |
| natural infection, transovarial transmission, and transstadial survival of rickettsia bellii in the tick ixodes loricatus (acari: ixodidae) from brazil. | an ixodes loricatus engorged female, infected with rickettsia bellii, was collected from an opossum (didelphis aurita) in mogi das cruzes, são paulo state, brazil. two consecutive laboratory tick generations (f(1) and f(2)) reared from this single engorged female were evaluated for rickettsia infection by polymerase chain reaction (pcr) targeting specific rickettsia genes. immature ticks fed on naïve wistar rats (rattus norvegicus) and adult ticks fed on opossum (d. aurita), both free of ticks a ... | 2006 | 17114723 |
| isolation of rickettsia rickettsii and rickettsia bellii in cell culture from the tick amblyomma aureolatum in brazil. | brazilian spotted fever (bsf) is a highly lethal disease caused by rickettsia rickettsii. in the present study, rickettsial infection was evaluated in 669 amblyomma aureolatum adult ticks collected from naturally infested dogs in taiaçupeba, a bsf-endemic area in the state of são paulo. ten (1.49%) ticks were infected with rickettsia bellii, and 6 (0.89%) ticks were infected with r. rickettsii. both rickettsia species were isolated and established in vero cell cultures. the rickettsia isolates w ... | 2006 | 17114770 |
| isolation of rickettsia rhipicephali and rickettsia bellii from haemaphysalis juxtakochi ticks in the state of são paulo, brazil. | in the present study, attempts to isolate rickettsia in cell culture were performed individually in seven specimens of haemaphysalis juxtakochi ticks collected in the state of são paulo (southeastern brazil). rickettsia was successfully isolated by the shell vial technique and established in vero cell culture from six ticks (six isolates). dna extracted from infected cells of these isolates was tested by pcr and dna sequencing, using genus-specific rickettsia primers targeting the genes glta, ht ... | 2007 | 17142361 |
| infection by rickettsia bellii and candidatus "rickettsia amblyommii" in amblyomma neumanni ticks from argentina. | the tick species, amblyomma neumanni (acari: ixodidae) is the most frequent tick parasitizing humans in northwestern argentina. the present study evaluated the rickettsial infection among 55 a. neumanni adult free-living ticks collected in dean funes, córdoba province. ticks were individually processed by the hemolymph test with gimenez staining, isolation of rickettsia in vero cell culture by the shell vial technique, and polymerase chain reaction (pcr) targeting the citrate synthase rickettsia ... | 2007 | 17264991 |
| prevalence of rickettsia infection in dogs from the urban and rural areas of monte negro municipality, western amazon, brazil. | the present study evaluated the rickettsial infection among dogs living in the rural and urban areas of monte negro, state of rondônia, western brazilian amazon. canine sera were tested by the indirect immunofluorescence assay (ifa) using six rickettsial antigens: rickettsia bellii, rickettsia amblyommii, rickettsia rhipicephali, rickettsia rickettsii, rickettsia parkeri, and rickettsia felis. while the first three rickettsia species are known to occur in the study site, the latter three species ... | 2007 | 17627445 |
| lateral gene transfer between obligate intracellular bacteria: evidence from the rickettsia massiliae genome. | rickettsia massiliae is a tick-borne obligate intracellular alpha-proteobacteria causing spotted fever in humans. here, we present the sequence of its genome, comprising a 1.3-mb circular chromosome and a 15.3-kb plasmid. the chromosome exhibits long-range colinearity with the other spotted fever group rickettsia genomes, except for a large fragment specific to r. massiliae that contains 14 tra genes presumably involved in pilus formation and conjugal dna transfer. we demonstrate that the tra re ... | 2007 | 17916642 |
| rickettsia infection in five areas of the state of são paulo, brazil. | this study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of são paulo. eight flea species (adoratopsylla antiquorum antiquorum, ctenocephalides felis felis, polygenis atopus, polygenis rimatus, polygenis roberti roberti, polygenis tripus, rhopalopsyllus lugubris, and rhopalopsyllus lutzi lutzi), and five tick species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, ixodes loricatus, and rhipicephalus sanguineus) were ... | 2007 | 18094887 |
| rickettsial infection in capybaras (hydrochoerus hydrochaeris) from são paulo, brazil: serological evidence for infection by rickettsia bellii and rickettsia parkeri. | in brazil, capybaras (hydrochoerus hydrochaeris) are important hosts for amblyomma ticks, which in turn can transmit rickettsiae to humans and animals. therefore, capybaras are potential sentinels for rickettsial infection. | 2007 | 18320102 |
| canine infection by rickettsiae and ehrlichiae in southern brazil. | this study evaluated the infection caused by rickettsia and ehrlichia agents among dogs in southern brazil. a total of 389 dogs were tested by the indirect immunofluorescence assay (ifa) for rickettsia rickettsii, rickettsia parkeri, rickettsia amblyommii, rickettsia rhipicephali, rickettsia bellii, and ehrlichia canis. overall, 42.4% (165/389) of the dogs were seroreactive to at least one rickettsia species, but only 11 canine sera reacted with another rickettsia species without reacting with r ... | 2008 | 18606772 |
| new epidemiological data on brazilian spotted fever in an endemic area of the state of são paulo, brazil. | the present work evaluated rickettsial infection in dogs and their ticks in an area endemic for brazilian spotted fever (bsf) in the metropolitan area of são paulo, brazil, where the tick amblyomma aureolatum was presumed to be the vector of the disease. ticks were collected on dogs from 185 houses, encompassing single infestations by rhipicephalus sanguineus, amblyomma aureolatum, amblyomma longirostre, or amblyomma sp. in dogs from 60 (32.4%), 77 (41.6%), 2 (1.1%), and 25 (13.5%) houses, respe ... | 2008 | 18847319 |
| molecular detection of rickettsia, coxiella and rickettsiella dna in three native australian tick species. | three australian native animal species yielded 60 samples composed of three indigenous ticks. hosts included twelve koalas, two echidnas and one wombat from victoria, and ticks were of the species ixodes tasmani (n = 42), bothriocroton concolor (n = 8) and b. auruginans (n = 10), respectively. pcr screening and sequencing detected a species of coxiella, sharing closest sequence identity to c. burnetii (>98%), in all b. auruginans, as well as a species of rickettsia, matching closest to r. massil ... | 2009 | 19296229 |
| molecular detection of rickettsia bellii, rickettsia montanensis, and rickettsia rickettsii in a dermacentor variabilis tick from nature. | rickettsial diseases, such as rocky mountain spotted fever, pose a public health threat because of humans' interrelationship with common arthropod species, such as ticks, mites, fleas, and lice. individuals may come in contact with these vectors of disease on a fairly regular basis either directly or indirectly through pets or wildlife species, at home or in recreational areas. therefore, it is of vital importance to know and understand the geographical distribution and prevalence of disease and ... | 2010 | 19485770 |
| prediction of rickettsial skin eschars in humans using an experimental guinea pig model. | until now, when a new rickettsia species was isolated in a tick, it was not possible to predict whether it was a human pathogen or if it would cause a skin eschar at the infection site. guinea pigs are injected intradermally with 25 different rickettsia species or subspecies: 16 induced an eschar, 5 induced inflammatory lesions and 4 have no effect. we observed that the occurrence of skin eschars in this model was significantly correlated (p <0.05) with observations of skin eschars in humans (14 ... | 2009 | 19527779 |
| ecology of rickettsia in south america. | until the year 2000, only three rickettsia species were known in south america: (i) rickettsia rickettsii, transmitted by the ticks amblyomma cajennense, and amblyomma aureolatum, reported in colombia, argentina, and brazil, where it is the etiological agent of rocky mountain spotted fever; (ii) rickettsia prowazekii, transmitted by body lice and causing epidemic typhus in highland areas, mainly in peru; (iii) rickettsia typhi, transmitted by fleas and causing endemic typhus in many countries. d ... | 2009 | 19538276 |
| rickettsial infection in amblyomma nodosum ticks (acari: ixodidae) from brazil. | the rickettsial infections in 174 amblyomma nodosum found on passeriform birds in the atlantic forest, eastern brazil, have recently been evaluated. rickettsiae were successfully isolated from two ticks, using cultures of vero cells. both isolates were molecularly characterised, using the rickettsial genes glta and htra and, when possible, also ompa and ompb. portions of the glta and htra genes from one of the rickettsial isolates were found be closely match the corresponding genbank sequences f ... | 2009 | 19583912 |
| [survey of rickettsia spp in the ticks amblyomma cajennense and amblyomma dubitatum in the state of são paulo]. | the presence of rickettsial infection was surveyed in 3,545 amblyomma cajennense ticks and 2,666 amblyomma dubitatum ticks. using the hemolymph test, polymerase chain reaction and isolation of rickettsia in cell cultures, all of the amblyomma cajennense were negative, whereas 634 (23.8%) of the amblyomma dubitatum ticks were shown to be infected with rickettsia bellii. | 2009 | 19684990 |
| the genome of the amoeba symbiont "candidatus amoebophilus asiaticus" reveals common mechanisms for host cell interaction among amoeba-associated bacteria. | protozoa play host for many intracellular bacteria and are important for the adaptation of pathogenic bacteria to eukaryotic cells. we analyzed the genome sequence of "candidatus amoebophilus asiaticus," an obligate intracellular amoeba symbiont belonging to the bacteroidetes. the genome has a size of 1.89 mbp, encodes 1,557 proteins, and shows massive proliferation of is elements (24% of all genes), although the genome seems to be evolutionarily relatively stable. the genome does not encode pat ... | 2010 | 20023027 |
| genome analysis of microorganisms living in amoebae reveals a melting pot of evolution. | abstract amoebae-resistant microorganisms exhibit a specific lifestyle. unlike allopatric specialized intracellular pathogens, they have not specialized because they infect the amoebae via amoebal attack and present a sympatric lifestyle with species from different phyla. in this review, we compare the genomes from bacteria (legionella pneumophila, legionella drancourtii, candidatus'protochlamydia amoebophila,'rickettsia bellii, candidatus'amoebophilus asiaticus') and a virus (mimivirus) that mu ... | 2010 | 20132312 |
| 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 |
| experimental infection of the opossum didelphis aurita by rickettsia felis, rickettsia bellii, and rickettsia parkeri and evaluation of the transmission of the infection to ticks amblyomma cajennense and amblyomma dubitatum. | this work evaluated the infection of opossums (didelphis aurita) by rickettsia felis, rickettsia bellii, and rickettsia parkeri and their role as amplifier hosts for horizontal transmission to amblyomma cajennense and/or amblyomma dubitatum ticks. infection in d. aurita was induced by intraperitoneal inoculation with r. felis (n = 4 opossums), r. bellii (n = 4), and r. parkeri (n = 2). another group of six opossums were inoculated intraperitoneally with leibovitz-15 sterile culture medium, repre ... | 2010 | 20455783 |
| survey of ticks (acari: ixodidae) and their rickettsia in an atlantic rain forest reserve in the state of são paulo, brazil. | the current study investigated the occurrence of ticks and their rickettsiae in the serra do mar state park, which encompasses one of the largest atlantic rain forest reserves of brazil. from july 2008 to june 2009, a total of 2439 ticks (2,196 free living and 243 collected on hosts) was collected, encompassing the following 13 species: amblyomma aureolatum (pallas), amblyomma brasiliense aragao, amblyomma dubitatum neumann, amblyomma fuscum neumann, amblyomma incisum neumann, amblyomma longiros ... | 2010 | 20939390 |
| rickettsial infection in domestic mammals and their ectoparasites in el valle de antón, coclé, panamá. | the present research evaluated the presence of rickettsia spp. on ectoparasites of horses and dogs (using pcr techniques), and their sera (using immunofluorescence assay) in el valle de antón town in panama. a total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks rhipicephalus sanguineus, amblyomma ovale, amblyomma oblongoguttatum, and the flea ctenocephalides felis), and two tick species on horses (amblyomma cajennense and dermacentor nitens). dna ... | 2010 | 21144663 |
| seroprevalence of rickettsia bellii and rickettsia felis in dogs, são josé dos pinhais, state of paraná, brazil. | brazilian spotted fever (bsf) is a vector-borne zoonosis caused by rickettsia rickettsii bacteria. dogs can be host sentinels for this bacterium. the aim of the study was to determine the presence of antibodies against rickettsia spp. in dogs from the city of são josé dos pinhais, state of paraná, southern brazil, where a human case of bsf was first reported in the state. between february 2006 and july 2007, serum samples from 364 dogs were collected and tested at 1:64 dilutions by indirect immu ... | 2010 | 21184698 |
| tick-borne bacteria in free-living jaguars (panthera onca) in pantanal, brazil. | abstract tick-borne bacteria were investigated in 10 free-living jaguars and their ticks in the pantanal biome, brazil. jaguar sera were tested by indirect fluorescent antibody assays using rickettsia rickettsii, rickettsia parkeri, rickettsia amblyommii, rickettsia rhipicephali, rickettsia felis, rickettsia bellii, ehrlichia canis, and coxiella burnetii as crude antigens. all 10 jaguar sera reacted (titer ≥64) to at least one rickettsia species; 4 and 3 sera reacted with e. canis and c. burneti ... | 2011 | 21612532 |
| rickettsia monteiroi sp. nov., infecting the tick amblyomma incisum in brazil. | free-living adult amblyomma incisum ticks were collected in an atlantic rainforest area at intervales state park, state of s+úo paulo, brazil. from an a. incisum specimen, rickettsiae were successfully isolated in vero cell culture by the shell vial technique. rickettsial isolation was confirmed by optical microscopy, transmission electron microscopy, and pcrs targeting portions of the rickettsial genes glta, htra, rrs, and sca1 on infected cells. fragments of 1,089, 457, 1,362, and 443 nucleoti ... | 2011 | 21685169 |
| Effect of Forest Fragmentation on Tick Infestations of Birds and Tick Infection Rates by Rickettsia in the Atlantic Forest of Brazil. | Habitat loss and modifications affect biodiversity, potentially contributing to outbreaks of infectious diseases. We evaluated if the patch sizeinfragmented areas of Atlantic Forest in southeastern Brazil influences the diversity of forest birds and consequently the prevalence of ticks on birds and the rickettsial infection of these ticks. During 2 years, we collected ticks from birds in 12 sites: four small forest patches (80-140 ha), four large ones (480-1,850 ha), and four forest control area ... | 2011 | 22173291 |
| 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 ... | 2012 | 22056929 |
| development of shuttle vectors for transformation of diverse rickettsia species. | plasmids have been identified in most species of rickettsia examined, with some species maintaining multiple different plasmids. three distinct plasmids were demonstrated in rickettsia amblyommii aar/sc by southern analysis using plasmid specific probes. copy numbers of pram18, pram23 and pram32 per chromosome in aar/sc were estimated by real-time pcr to be 2.0, 1.9 and 1.3 respectively. cloning and sequencing of r. amblyommii aar/sc plasmids provided an opportunity to develop shuttle vectors fo ... | 2011 | 22216299 |
| rickettsia bellii infecting amblyomma sabanerae ticks in el salvador. | four amblyomma sabanerae ticks collected from a turtle (kinosternon sp.) in san miguel, el salvador, were found by molecular analysis to be infected by rickettsia bellii. we provide the first report of rickettsia bellii in central america, and the first report of a rickettsia species in el salvador. | 2012 | 23265378 |
| microbial community of predatory bugs of the genus macrolophus (hemiptera: miridae). | the predatory mirids of the genus macrolophus are key natural enemies of various economically important agricultural pests. both m. caliginosus and m. pygmaeus are commercially available for the augmentative biological control of arthropod pests in european greenhouses. the latter species is known to be infected with wolbachia -inducing cytoplasmic incompatibility in its host- but the presence of other endosymbionts has not been demonstrated. in the present study, the microbial diversity was exa ... | 2012 | 22376198 |
| transcriptional analysis of the conjugal transfer genes of rickettsia bellii rml 369-c. | rickettsia bellii is an obligate intracellular bacterium that is one of the few rickettsiae that encode a complete set of conjugative transfer (tra) genes involved in bacterial conjugation and has been shown to exhibit pili-like structures. the reductive genomes of rickettsiae beg the question whether the tra genes are nonfunctional or functioning to enhance the genetic plasticity and biology of rickettsiae. we characterized the transcriptional dynamics of r. bellii tra genes in comparison to ge ... | 2015 | 26352829 |
| epidemiological surveillance of capybaras and ticks on warning area for brazilian spotted fever. | the vulnerability of tropical developing countries to the emerging disease constitutes a critical phenomenon in which the invasion of wild niches by human hosts, contributes to expansion of zoonotic diseases, such as the brazilian spotted fever (bsf). this study performed a diagnosis of species occurrence of their hosts (hydrochoerus hydrochaeris) and vectors (amblyomma sculptum and amblyomma dubitatum) on the warning area for this reemerging disease in brazil. | 2015 | 27047211 |
| rickettsia spp. in seabird ticks from western indian ocean islands, 2011-2012. | we found a diversity of rickettsia spp. in seabird ticks from 6 tropical islands. the bacteria showed strong host specificity and sequence similarity with strains in other regions. seabird ticks may be key reservoirs for pathogenic rickettsia spp., and bird hosts may have a role in dispersing ticks and tick-associated infectious agents over large distances. | 0 | 24751287 |
| detection of rickettsia bellii and rickettsia amblyommii in amblyomma longirostre (acari: ixodidae) from bahia state, northeast brazil. | studies investigating rickettsial infections in ticks parasitizing wild animals in the northeast region of brazil have been confined to the detection of rickettsia amblyommii in immature stages of amblyomma longirostre collected from birds in the state of bahia, and in immatures and females of amblyomma auricularium collected from the striped hog-nosed skunk (conepatus semistriatus) and armadillos (euphractus sexcinctus) in the state of pernambuco. the current study extends the distribution of r ... | 2015 | 26413074 |
| rickettsia bellii, rickettsia amblyommii, and laguna negra hantavirus in an indian reserve in the brazilian amazon. | the purpose of this study was to identify the presence of rickettsia and hantavirus in wild rodents and arthropods in response to an outbreak of acute unidentified febrile illness among indians in the halataikwa indian reserve, northwest of the mato grosso state, in the brazilian amazon. where previously surveillance data showed serologic evidence of rickettsia and hantavirus human infection. | 2014 | 24742108 |
| rickettsia vini n. sp. (rickettsiaceae) infecting the tick ixodes arboricola (acari: ixodidae). | recently, a new rickettsia named 'candidatus rickettsia vini' belonging to the spotted fever group has been molecularly detected in ixodes arboricola ticks in spain, the czech republic, slovakia and turkey, with prevalence reaching up to 100 %. the aim of this study was to isolate this rickettsia in pure culture, and to describe it as a new rickettsia species. | 2016 | 27565956 |
| motility characteristics are altered for rickettsia bellii transformed to overexpress a heterologous ricka gene. | the rickettsial protein ricka activates host cell factors associated with the eukaryotic actin cytoskeleton and is likely involved with rickettsial host cell binding and infection and the actin-based motility of spotted fever group rickettsiae. the ricka gene sequence and protein vary substantially between rickettsia species, as do observed motility-associated phenotypes. to help elucidate the function of ricka and determine the effects of species-specific ricka variations, we compared extracell ... | 2013 | 24296498 |
| molecular detection of rickettsia, anaplasma, coxiella and francisella bacteria in ticks collected from artiodactyla in thailand. | a total of 79 ticks collected from sambar deer (cervus unicolor), barking deer (muntiacus muntjak) and wild boar (sus scrofa) were examined by pcr for the presence of rickettsia, anaplasma, coxiella, and francisella bacteria. of the 79 ticks, 13% tested positive for rickettsia, 15% tested positive for anaplasma, 4% tested positive for coxiella, and 3% tested positive for francisella. interestingly, triple infection with anaplasma, rickettsia and francisella was determined in a dermacentor auratu ... | 2016 | 26934997 |
| the bacterial microbiome of dermacentor andersoni ticks influences pathogen susceptibility. | ticks are of medical importance owing to their ability to transmit pathogens to humans and animals. the rocky mountain wood tick, dermacentor andersoni, is a vector of a number of pathogens, including anaplasma marginale, which is the most widespread tick-borne pathogen of livestock. although ticks host pathogenic bacteria, they also harbor bacterial endosymbionts that have a role in tick physiology, survival, as well as pathogen acquisition and transmission. the goal of this study was to charac ... | 2016 | 26882265 |
| a serological and molecular survey of babesia vogeli, ehrlichia canis and rickettsia spp. among dogs in the state of maranhão, northeastern brazil. | this study evaluated exposure and infection by tick-borne agents (babesia vogeli, ehrlichia canis and rickettsia spp.) in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of chapadinha, state of maranhão, northeastern brazil, using molecular and serological methods. overall, 16.1% of the sampled dogs (52/322) were seroreactive to b. vogeli, with endpoint titers ranging from 40 to 640. for e. canis, 14.6% of the dogs (47/322) were seroreactive, with endpoint titers from 80 ... | 2015 | 25909250 |
| bacteria of the genera ehrlichia and rickettsia in ticks of the family ixodidae with medical importance in argentina. | the aim of this study was to get an overview about the occurrence of bacteria from the genus ehrlichia and rickettsia in ixodid ticks with medical importance in argentina. therefore, in 2013 and 2014, free-living ticks were collected in different provinces of northern argentina. these ticks were determined as amblyomma sculptum, amblyomma neumanni, amblyomma parvum, amblyomma triste, amblyomma ovale, amblyomma tonelliae and haemaphysalis juxtakochi. all samples were tested to determine the infec ... | 2017 | 27812828 |
| microorganisms in ticks (acari: ixodidae) collected on marsupials and rodents from santa catarina, paraná and mato grosso do sul states, brazil. | information about tick fauna and monitoring of pathogen prevalences in ticks (acari: ixodidae) in various habitat types can enhance knowledge about the epidemiology of tick-borne pathogens in brazil. this work shows the results of a study of tick parasitism of wild rodents and marsupials collected in seven localities in the southern part of brazil, within atlantic forest and cerrado biomes. a total of 61 ticks were collected from small mammals, and after identification to the species level, the ... | 2017 | 27769655 |
| host nuclear genotype influences phenotype of a conditional mutualist symbiont. | arthropods commonly carry maternally inherited intracellular bacterial symbionts that may profoundly influence host biology and evolution. the intracellular symbiont rickettsia sp. nr. bellii swept rapidly into populations of the sweetpotato whitefly bemisia tabaci in the south-western usa. previous laboratory experiments showed female-bias and fitness benefits were associated with rickettsia infection, potentially explaining the high frequencies of infection observed in field populations, but t ... | 2017 | 27748992 |
| detection of rickettsiae in fleas and ticks from areas of costa rica with history of spotted fever group rickettsioses. | outbreaks of spotted fevers have been reported in costa rica since the 1950s, although vectors responsible for transmission to humans have not been directly identified. in this study, species of rickettsia were detected in ectoparasites from costa rica, mostly from five study sites where cases of spotted fevers have been reported. ticks and fleas were collected using drag cloths or directly from domestic and wild animals and pooled according to species, host, and location. pools were analyzed in ... | 2016 | 27592065 |
| rickettsia (rickettsiales: rickettsiaceae) vector biodiversity in high altitude atlantic forest fragments within a semiarid climate: a new endemic area of spotted-fever in brazil. | rickettsioses are re-emerging vector-borne zoonoses with a global distribution. recently, rickettsia sp. strain atlantic rainforest has been associated with new human spotted-fever (sf) cases in brazil, featuring particular clinical signs: eschar formation and lymphadenopathy. these cases have been associated with the tick species, amblyomma ovale from 2010 until 2015, the brazilian health department confirmed 11 human sf cases in the maciço de baturité region, ceará, brazil. the present study r ... | 2016 | 27480099 |
| development of a rickettsia bellii-specific taqman assay targeting the citrate synthase gene. | rickettsia bellii is a rickettsial species of unknown pathogenicity that infects argasid and ixodid ticks throughout the americas. many molecular assays used to detect spotted fever group (sfg) rickettsia species do not detect r. bellii, so that infection with this bacterium may be concealed in tick populations when assays are used that screen specifically for sfg rickettsiae. we describe the development and validation of a r. bellii-specific, quantitative, real-time pcr taqman assay that target ... | 2016 | 27473178 |
| ecology of a tick-borne spotted fever in southern brazil. | rio grande do sul is the southernmost state of brazil, bordering uruguay. clinical cases of spotted fever group (sfg) rickettsiosis were recently reported in rio grande do sul. none of these cases was lethal, and all were confirmed by seroconversion to r. rickettsii antigens. because serological cross-reactions are well known to occur between different sfg agents, the sfg agent responsible for the clinical cases remains unknown in rio grande do sul, where no rickettsial agent is known to infect ... | 2016 | 27392739 |
| a nightmare for males? a maternally transmitted male-killing bacterium and strong female bias in a green lacewing population. | for maternally transmitted microbes, a female-biased host sex ratio is of reproductive advantage. here we found a strong female bias in a field population of the green lacewing, mallada desjardinsi (insecta; neuroptera). this bias was attributed to the predominance of individuals harboring a maternally inherited male-killing bacterium that was phylogenetically closely related to the plant-pathogenic spiroplasma phoeniceum and spiroplasma kunkelii. among 35 laboratory-reared broods produced by wi ... | 2016 | 27304213 |
| sequencing and comparison of the rickettsia genomes from the whitefly bemisia tabaci middle east asia minor i. | the whitefly, bemisia tabaci, harbors the primary symbiont 'candidatus portiera aleyrodidarum' and a variety of secondary symbionts. among these secondary symbionts, rickettsia is the only one that can be detected both inside and outside the bacteriomes. infection with rickettsia has been reported to influence several aspects of the whitefly biology, such as fitness, sex ratio, virus transmission and resistance to pesticides. however, mechanisms underlying these differences remain unclear, large ... | 2016 | 27273750 |
| serologic evidence of the exposure of small mammals to spotted-fever rickettsia and rickettsia bellii in minas gerais, brazil. | sources of pathogenic rickettsia in wildlife are largely unknown in brazil. in this work, potential tick vectors and seroreactivity of small mammals against four spotted-fever group rickettsia (r. rickettsii, r. parkeri, r. amblyommii and r. rhipicephali) and rickettsia bellii from peri-urban areas of uberlândia, a major town in brazil, are described for the first time. | 2016 | 27031460 |
| dynamics of exposure to rickettsia parkeri in cattle in the paraná river delta, argentina. | several cases of human rickettsiosis caused by rickettsia parkeri were recently documented in the paraná river delta of argentina, where the tick vector is amblyomma triste koch. as cattle suffer recurrent a. triste infestations, they are at risk of becoming infected with r. parkeri herein we investigated the dynamics of r. parkeri and its a. triste vector in a herd of beef cattle. cattle were followed for 18 mo and samples were analyzed for the presence of antibodies against four rickettsia spe ... | 2016 | 26794232 |
| rickettsia bellii in amblyomma rotundatum ticks parasitizing rhinella jimi from northeastern brazil. | this study evaluated rickettsial infection in amblyomma rotundatum ticks collected from toads (rhinella jimi) in the brazilian caatinga biome, an unique semiarid region of south america. tick infestations were observed in 57.8% toads (26/45); mean infestation: 1.6 ticks/toad. dna extraction from 42 ticks (6 larvae, 22 nymphs and 11 female adults) was tested by polymerase chain reaction (pcr) targeting rickettsia organisms, which were detected in 100% of the ticks. amplicons' dna sequences were i ... | 2016 | 26344601 |
| seroprevalence of rickettsia spp. in equids and molecular detection of 'candidatus rickettsia amblyommii' in amblyomma cajennense sensu lato ticks from the pantanal region of mato grosso, brazil. | the aim of the study was to evaluate exposure of equids to rickettsial agents (rickettsia rickettsii, rickettsia parkeri, 'candidatus rickettsia amblyommii', rickettsia rhipicephali, and rickettsia bellii) and rickettsial infection in ticks of a pantanal region of brazil. sera of 547 equids (500 horses and 47 donkeys) were evaluated by indirect immunofluorescence assay. in total, 665 adults and 106 nymphal pools of amblyomma cajennense f. sensu lato, 10 dermacentor nitens neumann ticks, and 88 l ... | 2014 | 26309313 |
| bacteria of the genus rickettsia in ticks (acari: ixodidae) collected from birds in costa rica. | the aim of this study was to document the presence of rickettsia spp. in ticks parasitizing wild birds in costa rica. birds were trapped at seven locations in costa rica during 2004, 2009, and 2010; then visually examined for the presence of ticks. ticks were identified, and part of them was tested individually for the presence of rickettsia spp. by polymerase chain reaction (pcr) using primers targeting fragments of the rickettsial genes glta and ompa. pcr products were dna-sequenced and analyz ... | 2015 | 25869035 |
| molecular detection of rickettsia bellii in amblyomma rotundatum from imported red-footed tortoise (chelonoides carbonaria). | introduction of exotic ticks and pathogens through international animal trade (farm animals and pets) is a serious threat to public health and local fauna. rapid and correct identification of potential threats is an important step on the way to conduct an efficient control of imported pests. in this report we describe the molecular identification of the neotropic tick amblyomma rotundatum intercepted from red-footed tortoise (chelonoides carbonaria), imported to israel from florida, usa. molecul ... | 2015 | 25865033 |
| rickettsial agents in avian ixodid ticks in northeast brazil. | birds are important in the maintenance and spread of ticks and tick-borne diseases. in this context we screened birds in the atlantic forest north of the são francisco river and caatinga in northeast brazil. in the atlantic forest amblyomma longirostre, amblyomma nodosum, amblyomma varium and amblyomma auricularium were identified. a. longirostre was infected by "candidatus rickettsia amblyommii" and a. nodosum by a rickettsia parkeri-like agent. in caatinga, amblyomma parvum and a. auricularium ... | 2015 | 25800099 |
| molecular detection of the human pathogenic rickettsia sp. strain atlantic rainforest in amblyomma dubitatum ticks from argentina. | to date, three tick-borne pathogenic rickettsia species have been reported in different regions of argentina, namely, r. rickettsii, r. parkeri, and r. massiliae. however, there are no reports available for the presence of tick-borne pathogens from the northeastern region of argentina. this study evaluated the infection with rickettsia species of amblyomma dubitatum ticks collected from vegetation and feeding from capybaras (hydrochoerus hydrochaeris) in northeastern argentina. from a total of 3 ... | 2015 | 25700048 |
| experimental infection with rickettsia rickettsii in an amblyomma dubitatum tick colony, naturally infected by rickettsia bellii. | amblyomma dubitatum engorged females, naturally infected by rickettsia bellii, were used to establish a laboratory colony. larvae, nymphs, and adults were exposed to two strains of rickettsia rickettsii by feeding on needle-inoculated guinea pigs, and thereafter reared on uninfected guinea pigs. after acquisition feeding, engorged larvae and nymphs molted to nymphs and adults, respectively, which were shown to be infected (confirming transstadial perpetuation), and were able to transmit both str ... | 2014 | 25108783 |
| characterization of the symbiont rickettsia in the mirid bug nesidiocoris tenuis (reuter) (heteroptera: miridae). | nesidiocoris tenuis (reuter) (heteroptera: miridae) is an omnivorous insect used for biological control. augmentative release and conservation of n. tenuis have been used for pest control in tomato crops. intracellular bacterial symbionts of arthropods are common in nature and have diverse effects on their hosts; in some cases they can dramatically affect biological control. fingerprinting methods showed that the symbiotic complex associated with n. tenuis includes wolbachia and rickettsia. rick ... | 2014 | 25062354 |
| molecular detection of rickettsia species in amblyomma ticks collected from snakes in thailand. | some reptile ticks are potential vectors of pathogens such as spotted fever group (sfg) rickettsiae. here, we report for the first time in detail the molecular evidence, dna sequences and phylogenetic studies, for the presence of rickettsia spp. in amblyomma ticks (amblyomma helvolum and amblyomma varanense) from snakes in thailand. a total of 24 tick samples was collected from 4 snake species and identified. a phylogenetic analysis inferred from the partial sequences of the glta gene indicated ... | 2014 | 25027232 |
| molecular detection of rickettsia bellii and rickettsia sp. strain colombianensi in ticks from cordoba, colombia. | the purpose of this study was to provide molecular evidence of rickettsia spp. in ticks collected from 2 sites of cordoba. from may to june 2009, 1069 amblyomma cajennense ticks were removed from 40 capybaras (hydrochoerus hydrochaeris) in a rural locality of monteria. furthermore, 458 amblyomma sp. larvae and 20 amblyomma sp. nymphs were collected in a rural locality of los cordobas (cordoba) by drag sampling on vegetation (n=1547). ticks were grouped into pools and tested for rickettsial infec ... | 2014 | 24378078 |
| environmental infestation and rickettsial infection in ticks in an area endemic for brazilian spotted fever. | brazilian spotted fever (bsf), caused by rickettsia rickettsii, is endemic in the municipality of americana, southeastern brazil, where the disease is transmitted by the tick amblyomma cajennense. this study evaluated the tick fauna and rickettsial infection in free-living ticks that were captured monthly using dry ice traps in areas endemic for bsf in americana, from july 2009 to june 2010. two tick species were captured: a. cajennense (6,122 larvae; 4,265 nymphs; 2,355 adults) and amblyomma du ... | 2013 | 24142167 |
| rickettsia bellii in ticks amblyomma varium koch, 1844, from birds in peru. | amazonian birds were caught and examined for the presence of ectoparasites in the allpahuayo mishana national reserve near iquitos, peru, from 13 to 16 august 2011. a total of 40 birds representing 16 species were examined. two birds (5%) were infested with 2 larvae of amblyomma varium koch, 1844, and one nymph of a. calcaratum neumann, 1899. the 2 larvae of a. varium were infected with rickettsia bellii. this is the first report of r. bellii in a. varium and also the first record of this ricket ... | 2012 | 22809734 |
| rickettsia amblyommatis infecting ticks and exposure of domestic dogs to rickettsia spp. in an amazon-cerrado transition region of northeastern brazil. | this study was performed in maranhão state, a transition area two brazilian biomes, amazon and cerrado. during 2011-2013, 1,560 domestic dogs were sampled for collection of serum blood samples and ticks in eight counties (3 within the amazon and 5 within the cerrado). a total of 959 ticks were collected on 150 dogs (9.6%). rhipicephalus sanguineus sensu lato (s.l.) was the most abundant tick (68% of all collected specimens), followed by amblyomma cajennense sensu lato (s.l.) (12.9%), amblyomma p ... | 2017 | 28594882 |
| molecular analyses reveal an abundant diversity of ticks and rickettsial agents associated with wild birds in two regions of primary brazilian atlantic rainforest. | brazilian wild birds are recognized as frequent and important hosts for immature stages of more than half of the 32 recognized species of amblyomma ticks recorded in that country. several species of amblyomma harbor rickettsial agents, including members of the spotted fever group (sfg). most studies on this topic relied primarily on morphological characterization and reported large portions of the collected ticks at the genus rather than species level. clearly, this factor may have contributed t ... | 2017 | 28479066 |