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[characterization of rickettsia spp. circulating in a silent peri-urban focus for brazilian spotted fever in caratinga, minas gerais, brazil].the present study was intended to characterize rickettsia spp. circulating in arthropod vectors in caratinga, minas gerais, brazil, by pcr and to investigate the presence of antibodies against the spotted fever rickettsiae group (sfrg) in dogs and horses. 2,610 arthropods were collected and taxonomically identified. dna samples obtained from these vectors were submitted to pcr and cycle-sequenced. ctenocephalides and amblyomma cajennense showed sequences presenting 100.0% homology with r. felis. ...200616583093
rickettsia massiliae human isolation. 200616634183
[evaluation of ectoparasites and hemoparasites in dogs kept in apartments and houses with yards in the city of juiz de fora, minas gerais, brazil].fleas and ticks transmit various pathogens while feeding on the blood of dogs. this study sought to verify the occurrence of ectoparasitism and hemoparasitism in dogs from two urban areas in the city of juiz de fora, minas gerais, brazil. between february and august 2003, 101 dogs were studied: 50 came from apartments in the downtown region and 51 from houses with grassy yards. the ectoparasites were collected and conserved in etanol 70%. the occurrence of hemoparasites was verified by examining ...200616646996
the genome of the obligately intracellular bacterium ehrlichia canis reveals themes of complex membrane structure and immune evasion strategies.ehrlichia canis, a small obligately intracellular, tick-transmitted, gram-negative, alpha-proteobacterium, is the primary etiologic agent of globally distributed canine monocytic ehrlichiosis. complete genome sequencing revealed that the e. canis genome consists of a single circular chromosome of 1,315,030 bp predicted to encode 925 proteins, 40 stable rna species, 17 putative pseudogenes, and a substantial proportion of noncoding sequence (27%). interesting genome features include a large set o ...200616707693
[ixodes ricinus. health risks and approaches in prevention].ticks belong to the parasitical mites. there are more than 1000 different species worldwide which do need blood of warm-blooded organisms for their own development. as ticks are well known to be vectors of several pathogens which could cause insidious infectious diseases, they are important in human and veterinarian medicine as well. it is not possible to control ticks in nature. therefore the first step should be an effective prevention. in case of a bite the tick must be removed as soon as pos ...200616719260
prevalence of theileria spp. infection in sheep in south khorasan province, iran.the prevalence of theileria spp. infection was studied in sheep in the south khorasan province in iran from 2003 to 2004. a total of 840 sheep from 34 flocks were clinically examined and investigated for the presence of theileria spp. in the appropriate blood smears and any tick species on the body of the animals. in this study, 11.9% of sheep were infected with theileria spp., with a parasitemia of 0.02-0.1%. differences in the infection rates were statistically significant among different area ...200616730905
molecular characterization of anaplasma platys strains from dogs in sicily, italy.the genetic diversity of anaplasma platys (rickettsiales: anaplasmataceae) strains is currently poorly defined. the present study was designed to characterize a. patys strains in dogs from palermo, sicily, italy, using a combination of pcr and sequence analysis of the 16s rdna, heat shock operon groesl and citrate synthase (glta) genes.200616872489
epidemiology and clinical features of mediterranean spotted fever in italy.mediterranean spotted fever is caused by rickettsia conorii and is transmitted to humans by rhipicephalus sanguineus, the common dog tick. it is characterized by the symptomatologic triad: fever, exanthema and "tache noire", the typical eschar at the site of the tick bite. in italy the most affected region is sicily. the seasonal peak of the disease (from june through september) occurs during maximal activity of immature stage ticks. severe forms of the disease have been reported in 6% of patien ...200616881414
assessment of the efficacy of parasiticides for the control of tick infection in dogs under field conditions: what's new?for their biological and ecological characteristics, ticks are vectors of the widest variety of pathogens causing tick-borne diseases (tbds). little information is available about the ways in which time spent by ticks to feed on hosts, transmission times and tbd prevention are related and it is exclusively limited to laboratory reports on adult stages. in particular, the time required by immature stages to transmit pathogens has not been determined for most tbds. considering their importance for ...200616881418
dog tick-borne diseases in sicily.in sicily many tick borne diseases are endemic, in particular way those that see like main carrier ticks that prefer, for their vital cycle, climatic conditions characterized by high temperatures and a warmth-humid atmosphere. the more important pathologies transmitted by ticks causing diseases in dogs are babesiosis and ehrlichiosis. borrelia burgdorferi, anaplasma phagocytophilum, rickettsia conorii, coxiella burnetii and tick transmitted encephalitis virus assume particular relevance because ...200616881419
isolation and identification of rickettsia massiliae from rhipicephalus sanguineus ticks collected in arizona.twenty rhipicephalus sanguineus ticks collected in eastern arizona were tested by pcr assay to establish their infection rate with spotted fever group rickettsiae. with a nested pcr assay which detects a fragment of the rickettsia genus-specific 17-kda antigen gene (htra), five ticks (25%) were found to contain rickettsial dna. one rickettsial isolate was obtained from these ticks by inoculating a suspension of a triturated tick into monolayers of vero e6 monkey kidney cells and xtc-2 clawed toa ...200616885311
infection of human endothelial cells with spotted fever group rickettsiae stimulates cyclooxygenase 2 expression and release of vasoactive prostaglandins.rickettsiae, a diverse group of obligately intracellular gram-negative bacteria, include etiologic agents of the spotted fever and typhus groups of diseases. rocky mountain spotted fever and boutonneuse fever, due to rickettsia rickettsii and r. conorii, respectively, are characterized by widespread infection of the vascular endothelium, microvascular injury, and vasculitis. cultured human endothelial cells (ec) are highly susceptible to infection and respond by altering the expression of adhesi ...200616926398
canine babesiosis: a brazilian perspective.canine babesiosis is highly endemic in brazil, caused by babesia canis and babesia gibsoni, both transmitted by rhipicephalus sanguineus ticks. the present review argues for a more adequate method of characterizing the babesia species infecting dogs and cats in different brazilian endemic zones. it advocates for a comprehensive understanding of the biology of r. sanguineus ticks under brazilian conditions in order to define the more effective preventive strategies against canine babesiosis and c ...200616962707
[study of foveae dorsales of nymphs and adults of four species of ticks (acari: ixodidae) by scanning electron microscopy].the foveae dorsalis, the external opening of the sex pheromone 2,6-dichlorophenol producer gland, of amblyomma cajennense, dermacentor nitens, rhipicephalus (boophilus) microplus and rhipicephalus sanguineus was studied with scanning electron microscopy. at least three specimens from each stage: unfed larvae, nymphs, females and males, and females fed for 4 to 6 days were examined. the foveae dorsales were not observed in larvae and r. (b.) microplus males. the foveae dorsales were observed as p ...200616978471
rickettsial agents in egyptian ticks collected from domestic animals.to assess the presence of rickettsial pathogens in ticks from egypt, we collected ticks from domestic and peridomestic animals between june 2002 and july 2003. dna extracts from 1019 ticks were tested, using pcr and sequencing, for anaplasma spp., bartonella spp., coxiella burnetii, ehrlichia spp., and rickettsia spp. ticks included: 29 argas persicus, 10 hyalomma anatolicum anatolicum, 55 hyalomma anatolicum excavatum, 174 hyalomma dromedarii, 2 hyalomma impeltatum, 3 hyalomma marginatum rufipe ...200617004028
babesia spp. identified by pcr in ticks collected from domestic and wild ruminants in southern switzerland.concurrent infections with vector-borne pathogens affected a cattle herd in switzerland, and one of the pathogens was identified as babesia bigemina, which had never been observed in this country before. therefore, a survey of the occurrence of ruminant babesia spp. and their tick vectors in switzerland was conducted. a total of 2,017 ticks were collected from sheep, goats, cattle, and wild ruminants (deer, roe deer, and chamois) in southern parts of switzerland and identified morphologically. t ...200617021198
molecular method for identification of rickettsia species in clinical and environmental samples.we present a pcr method targeting the 23s-5s internal transcribed spacer coupled with reverse line blotting that allows rickettsia species detection and identification in a single step. the method is highly sensitive and specific in identifying rickettsia species from both patient and environmental samples. the generic approach used allowed us to identify new pathogens.200617035495
phylogenetic analysis of "candidatus mycoplasma turicensis" isolates from pet cats in the united kingdom, australia, and south africa, with analysis of risk factors for infection.two hemotropic mycoplasmas have been recognized in cats, mycoplasma haemofelis and "candidatus mycoplasma haemominutum." we recently described a third feline hemoplasma species, designated "candidatus mycoplasma turicensis," in a swiss cat with hemolytic anemia. this isolate induced anemia after experimental transmission to two specific-pathogen-free cats and analysis of the 16s rrna gene revealed its close relationship to rodent hemotropic mycoplasmas. the agent was recently shown to be prevale ...200617035497
evaluation of an imidacloprid (8.8% w/w)--permethrin (44.0% w/w) topical spot-on and a fipronil (9.8% w/w)--(s)-methoprene (8.8% w/w) topical spot-on to repel, prevent attachment, and kill adult rhipicephalus sanguineus and dermacentor variabilis ticks on dogs.this study evaluated the effectiveness of two topical spot-on formulations, imidacloprid (8.8% w/w)--permethrin (44.0% w/w) and fipronil (9.8% w/w)--(s)-methoprene (8.8% w/w), to repel, prevent the attachment of, and kill adult rhipicephalus sanguineus and dermacentor variabilis on dogs. twelve purpose-bred beagles were distributed into three groups of four dogs each; one group served as untreated controls and each of the other two groups received one of the test products. dogs were exposed to 2 ...200617039441
epidemiology of rickettsioses in north africa.the first description of mediterranean spotted fever (msf) was made by conor and brush in 1910 in tunisia, where, at the same time, nicolle described the role of lice in transmission of epidemic typhus. however, along this century, there have been few and fragmentary reports about ecology and epidemiology of rickettsioses in north africa. this region was always considered, for these diseases, like other mediterranean regions. the most human tick-borne rickettsiosis known to occur in north africa ...200617114678
boutonneuse fever and climate variability.researchers have long appreciated the role of climate in vector-borne diseases, including the resurgence of boutonneuse fever (bf). portugal usually is classified as having temperate mediterranean climate. in this new century, in analyzing the data from the meteorology institute, this pattern has changed and an accentuated variability in climate is being observed. bf (febre escaro nodular) is endemic and high season is from late spring and summer. the brown dog tick rhipicephalus sanguineus. is ...200617114701
prevalence of spotted fever group rickettsia species detected in ticks in la rioja, spain.our objective was to learn the prevalence of spotted fever group (sfg) rickettsia detected in ticks in la rioja, in the north of spain. from 2001 to 2005, 496 ticks representing 7 tick species were analysed at the hospital de la rioja. ticks were removed from humans with or without rickettsial syndrome (n = 59) or collected from mammals (n = 371) or from vegetation by dragging (n = 66). the presence of sfg rickettsia in these ticks was investigated by semi-nested pcr (ompa gene) and sequencing. ...200617114730
spotted fever group rickettsiae in ticks feeding on humans in northwestern spain: is rickettsia conorii vanishing?during a 7-year study, we identified and analyzed by pcr 4,049 ticks removed from 3,685 asymptomatic patients in castilla y león (northwestern spain). a total of 320 ticks (belonging to 10 species) were pcr-positive for rickettsiae. comparison of amplicon sequences in databases enabled us to identify eight different spotted fever group (sfg) rickettsiae: rickettsia slovaca, rickettsia sp. irs3/irs4, r. massiliae/bar29, r. aeschlimannii, rickettsia sp. rpa4/dns14, r. helvetica, rickettsia sp. dms ...200617114733
rocky mountain spotted fever in arizona: documentation of heavy environmental infestations of rhipicephalus sanguineus at an endemic site.a recent epidemiologic investigation identified 16 cases and 2 deaths from rocky mountain spotted fever (rmsf) in two eastern arizona communities. prevalence studies were conducted by collecting free-living ticks (acari: ixodidae) from the home sites of rmsf patients and from other home sites within the community. dry ice traps and flagging confirmed heavy infestations at many of the home sites. only rhipicephalus sanguineus ticks were identified and all developmental stages were detected. it is ...200617114735
an outbreak of rocky mountain spotted fever associated with a novel tick vector, rhipicephalus sanguineus, in arizona, 2004: preliminary report.this study describes preliminary results of an investigation of rmsf in arizona associated with the brown dog tick, rhipicephalus sanguineus. high numbers of dogs and heavy infestations of ticks created a situation leading to human disease.200617114736
first molecular detection of r. conorii, r. aeschlimannii, and r. massiliae in ticks from algeria.ticks collected in northern algeria between may 2001 and november 2003 were tested by pcr for the presence of rickettsia spp. dna using primer amplifying glta and ompa genes. three different spotted fever group rickettsias were amplified from these ticks: r. conorii subsp. p. conorii strain malish in rhipicephalus sanguineus, r. aeschlimannii in hyalomma marginatum, and r. massiliae in rhipicephalus turanicus. our results confirm the presence of r. conorii in ticks in algeria and provide the fir ...200617114743
surveys on seroprevalence of canine monocytic ehrlichiosis among dogs living in the ivory coast and gabon and evaluation of a quick commercial test kit dot-elisa.canine monocytic ehlichiosis (cme), an enzootic disease in africa, has been studied in canine blood samples (serum). these dogs, without any clinical sign of disease, were living in abidjan (ivory coast) and in several small villages located in northeasst gabon (ogooué ivindo). the results obtained by indirect fluorescent antibody (ifa) test, used as a point of reference, and by a quick test dot-elisa were compared. blood samples taken from 390 asymptomatic dogs in 2003 (137 in ivory coast and 2 ...200617114755
spotted fever group rickettsial infection in dogs from eastern arizona: how long has it been there?a serosurvey of free-roaming dogs for antibodies to spotted fever group rickettsiae was conducted using archival samples that had been collected in the white mountain region of eastern arizona during a plague study in 1996. immunoglobulin g antibodies to rickettsia rickettsii (5.1%) and to r. rhipicephali (3.6%) were demonstrated, and no cross-reactive samples were identified. this study indicates that r. rickettsii was likely present in the dog populations in this area prior to the recognition ...200617114769
molecular typing of novel rickettsia rickettsii isolates from arizona.seven isolates of rickettsia rickettsii were obtained from a skin biopsy, two whole-blood specimens, and from rhipicephalus sanguineus ticks from eastern arizona. molecular typing of seven isolates of r. rickettsii and dna samples from two other rh. sanguineus ticks infected with r. rickettsii was conducted by pcr and dna sequencing of rompa and 12 variable-number tandem repeat regions (vntrs). all dna specimens from arizona were identical to each other and to reference human and dermacentor and ...200617114781
an investigation into the distribution, host-preference and population density of ixodid ticks affecting domestic animals in bangladesh.to study the distribution, host-preference and population density of ixodid ticks in bangladesh, an attempt was made to collect adult ticks from various host animals in three distinct topographic zones, viz. flood plains, hills and steppe 'barind'. five species of ixodid ticks were recorded, namely, boophilus microplus (56.3%), haemaphysalis bispinosa (11.3%), rhipicephalus sanguineus (14.7%), hyalomma anatolicum anatolicum (15.0%) and amblyomma testudinarium (2.8%). the data showed that b. micr ...200617243476
a case of histologically diagnosed tick infestation on the scalp of a korean child.a scalp mass surgically excised from a 4-year-old korean boy was identified as a tick through histological observations. in sections of the mass, characteristic features of a tick, including its gross contour, cuticular structures, well developed musculature and salivary glands, and the capitulum, were discovered. in particular, the capitulum is anteriorly protruded, which strongly suggests that the specimen be a hard tick of family ixodidae. however, the present histological features were not e ...200616809965
the environmental-endocrine basis of gynandromorphism (intersex) in a crustacean.commensurate with the decline in many crustacean populations has been an accumulation in reports of sexually ambiguous individuals within these populations. the cause of gynandromorphism or intersex among crustaceans is unknown. we show that gynandromorphism in the branchiopod crustacean daphnia magna is initiated by the sex-determining hormone methyl farnesoate when levels of the hormone are intermediate between low levels that stimulate the production of broods containing all female offspring ...200617205107
the complete mitochondrial genome of the sea spider nymphon gracile (arthropoda: pycnogonida).mitochondrial genomes form units of genetic information replicating indepentently from nuclear genomes. sequence data (most often from protein-coding genes) and other features (gene order, rna secondary structure) of mitochondrial genomes are often used in phylogenetic studies of metazoan animals from population to phylum level. pycnogonids are primarily marine arthropods, often considered closely related to chelicerates (spiders, scorpions and allies). however, due to their aberrant morphology ...200617087824
the complete mitochondrial genome of pseudocellus pearsei (chelicerata: ricinulei) and a comparison of mitochondrial gene rearrangements in arachnida.mitochondrial genomes are widely utilized for phylogenetic and population genetic analyses among animals. in addition to sequence data the mitochondrial gene order and rna secondary structure data are used in phylogenetic analyses. arachnid phylogeny is still highly debated and there is a lack of sufficient sequence data for many taxa. ricinulei (hooded tickspiders) are a morphologically distinct clade of arachnids with uncertain phylogenetic affinities.200717961221
the complete mitochondrial genome of the sea spider achelia bituberculata (pycnogonida, ammotheidae): arthropod ground pattern of gene arrangement.the phylogenetic position of pycnogonids is a long-standing and controversial issue in arthropod phylogeny. this controversy has recently been rekindled by differences in the conclusions based on neuroanatomical data concerning the chelifore and the patterns of hox expression. the mitochondrial genome of a sea spider, nymphon gracile (pycnogonida, nymphonidae), was recently reported in an attempt to address this issue. however, n. gracile appears to be a long-branch taxon on the phylogenetic tre ...200717908292
prevalence of ehrlichia canis (rickettsiales: anaplasmataceae) in dogs and rhipicephalus sanguineus (acari: ixodidae) ticks from brazil.the current study evaluated the prevalence of ehrlichia canis donatien and lestoquard in domestic dogs, canis familiaris l., and rhipicephalus sanguineus (latreille) (acari: ixodidae) ticks from different areas of brazil. in monte negro county (state of rondônia, brazilian western amazon), the indirect immunofluorescence assay detected e. canis-reactive antibodies (titer > or = 40) in 58/153 (37.9%) and 40/161 (24.8%) dogs from the urban and rural areas, respectively. these values were significa ...200717294930
detection of rickettsia rickettsii and bartonella henselae in rhipicephalus sanguineus ticks from california.sixty-two questing adult rhipicephalus sanguineus (latreille) ticks were collected by direct removal from blades of turfgrass and adjacent concrete walkways at a suburban home in riverside county, ca, and tested for the presence of rickettsia, bartonella, and ehrlichia dna. polymerase chain reaction (pcr) was used to amplify fragments of the 17-kda antigen gene and the rompa gene of the spotted fever group rickettsiae. one male tick contained r. rickettsii dna; its genotype differed from r. rick ...200717294935
uninfected mosquito bites confer protection against infection with malaria parasites.despite decades of research and multiple initiatives, malaria continues to be one of the world's most debilitating infectious diseases. new insights for malaria control and vaccine development will be essential to thwart the staggering worldwide impact of this disease (a. bjorkman and a. bhattarai, acta trop. 94:163-169, 2005); ultimately successful vaccine strategies will undoubtedly be multifactorial, incorporating multiple antigens and targeting diverse aspects of the malaria parasites' biolo ...200717339356
differential interaction of dendritic cells with rickettsia conorii: impact on host susceptibility to murine spotted fever rickettsiosis.spotted fever group rickettsioses are emerging and reemerging infectious diseases, some of which are life-threatening. in order to understand how dendritic cells (dcs) contribute to the host resistance or susceptibility to rickettsial diseases, we first characterized the in vitro interaction of rickettsiae with bone marrow-derived dcs (bmdcs) from resistant c57bl/6 (b6) and susceptible c3h/hen (c3h) mice. in contrast to the exclusively cytosolic localization within endothelial cells, rickettsiae ...200717403875
real-time pcr investigation of potential vectors, reservoirs, and shedding patterns of feline hemotropic mycoplasmas.three hemotropic mycoplasmas have been identified in pet cats: mycoplasma haemofelis, "candidatus mycoplasma haemominutum," and "candidatus mycoplasma turicensis." the way in which these agents are transmitted is largely unknown. thus, this study aimed to investigate fleas, ticks, and rodents as well as saliva and feces from infected cats for the presence of hemotropic mycoplasmas, to gain insight into potential transmission routes for these agents. dna was extracted from arthropods and from rod ...200717468284
life cycle of hepatozoon canis (apicomplexa: adeleorina: hepatozoidae) in the tick rhipicephalus sanguineus and domestic dog (canis familiaris).the life cycle of the apicomplexan protozoon hepatozoon canis in its natural hosts rhipicephalus sanguineus (tick) and canis familiaris (domestic dog) was studied in an experimental infection. tick nymphs were fed on a naturally infected dog, or they were infected by percutaneous injection of blood. dogs were inoculated by ingestion of adult ticks containing mature oocysts. gamonts were in syzygy 24 hr after percutaneous injection of ticks. early oocysts were detected 96 hr after nymph repletion ...200717539411
molecular typing of isolates of rickettsia rickettsii by use of dna sequencing of variable intergenic regions.rickettsia rickettsii, the causative agent of rocky mountain spotted fever, is found throughout the americas, where it is associated with different animal reservoirs and tick vectors. no molecular typing system currently exists to allow for the robust differentiation of isolates of r. rickettsii. analysis of eight completed genome sequences of rickettsial species revealed a high degree of sequence conservation within the coding regions of chromosomes in the genus. intergenic regions between codi ...200717553977
francisella tularensis, portugal. 200717561575
q fever (coxiella burnetii) among man and farm animals in north sinai, egypt.antibodies against coxiella burnetii were estimated among sheep, goats and camels (190), their owners (150 patients with pyrexia of unknown origin) and 30 normal individuals in north sinai over the 2006 by indirect immounofluorescence assay. nested polymerase chain reaction was used to detect com-1 gene (genetic target of c. burnetii) encoding a 27-kda outer membrane protein in the samples. c. burnetii ifa antibodies (igm & igg) in patients were 8 (5.3%) and a healthy control (3.3%). the overall ...200717580573
tick acquisition of ehrlichia canis from dogs treated with doxycycline hyclate.doxycycline generally alleviates clinical monocytic ehrlichiosis, but its efficacy in the control of monocytotropic ehrlichial pathogens requires further investigation. in this study, ehrlichia canis was detected in dogs treated with doxycycline for 14 days and in ticks fed on these dogs, suggesting that treated dogs can remain reservoirs for e. canis.200717606682
coinfection with multiple tick-borne and intestinal parasites in a 6-week-old dog.coinfection with ehrlichia canis, babesia canis, hepatozoon canis, isospora spp., giardia spp., and dipylidium caninum were detected in a 6-week-old dog. the effect of multi-pathogen infection was a fatal combination of gastrointestinal and hematologic abnormalities, including diarrhea, vomiting, anorexia, distended painful abdomen, intussusception, severe thrombocytopenia, anemia, and hypoproteinemia.200717616060
hepatozoon canis infection in slovakia: imported or autochthonous?tissue samples from nine red foxes (four samples of striated muscle tissue and five samples of heart tissue) that originated from the michalovce district (slovakia), an area with endemic occurrence of canine babesiosis were examined by pcr method using primers amplifying a fragment of the 18s rrna spanning the v4 region of babesia and theileria. an unexpected determination of 450 bp dna fragment of hepatozoon canis was found in four samples. partial sequences of the 18s rrna gene from the h. can ...200717627439
ehrlichia species in rhipicephalus sanguineus ticks in cameroon.ehrlichia and anaplasma species are tick-transmitted obligately intracellular bacteria that commonly cause disease in dogs worldwide. in addition to causing disease in canines, ehrlichia chaffeensis, ehrlichia ewingii, and anaplasma phagocytophilum are responsible for emerging and life-threatening human zoonoses in the united states. we previously reported a high prevalence of e. canis infection in cameroonian dogs based on serologic and molecular evidence. this study was undertaken to determine ...200717627442
molecular cloning and characterization of a highly selective chemokine-binding protein from the tick rhipicephalus sanguineus.ticks are blood-feeding parasites that secrete a number of immuno-modulatory factors to evade the host immune response. saliva isolated from different species of ticks has recently been shown to contain chemokine neutralizing activity. to characterize this activity, we constructed a cdna library from the salivary glands of the common brown dog tick, rhipicephalus sanguineus. pools of cdna clones from the library were transfected into hek293 cells, and the conditioned media from the transfected c ...200717640866
infection of ixodes scapularis ticks with rickettsia monacensis expressing green fluorescent protein: a model system.ticks (acari: ixodidae) are ubiquitous hosts of rickettsiae (rickettsiaceae: rickettsia), obligate intracellular bacteria that occur as a continuum from nonpathogenic arthropod endosymbionts to virulent pathogens of both arthropod vectors and vertebrates. visualization of rickettsiae in hosts has traditionally been limited to techniques utilizing fixed tissues. we report epifluorescence microscopy observations of unfixed tick tissues infected with a spotted fever group endosymbiont, rickettsia m ...200717125789
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 ...200717142361
differential clearance and immune responses to tick cell-derived versus macrophage culture-derived ehrlichia chaffeensis in mice.human monocytic ehrlichiosis is caused by a tick-transmitted rickettsia, ehrlichia chaffeensis. we recently reported that e. chaffeensis grown in tick cells expresses different proteins than bacteria grown in macrophages. therefore, we tested the hypothesis that immune responses against e. chaffeensis would be different if the mice are challenged with bacteria grown in macrophages or tick cells. we assessed the e. chaffeensis clearance from the peritoneum, spleen, and liver by c57bl/6j mice usin ...200717060466
species diversity and seasonality of free-living ticks (acari: ixodidae) in the natural habitat of wild marsh deer (blastocerus dichotomus) in southeastern brazil.this study evaluated the presence and seasonal activity of free-living ticks in remaining marsh areas by the paraná river, in brazil. eight field trips (once per season) for collection of ticks were performed during 2 years. using co2 traps, dragging, and visual inspection of vegetation, five free-living tick species were collected, in the following order of abundance: amblyomma cajennense, amblyomma dubitatum, amblyomma triste, amblyomma coelebs, and amblyomma nodosum. the seasonal pattern of a ...200716962241
hyalomma aegyptium as dominant tick in tortoises of the genus testudo in balkan countries, with notes on its host preferences.collection of 1327 ticks sampled throughout greece, bulgaria, romania and croatia, from 211 tortoises belonging to three species, testudo marginata schoepff, t. graeca linnaeus, and t. hermanni gmelin, revealed the presence of four species of ixodid ticks, namely hyalomma aegyptium (linnaeus), haemaphysalis sulcata canestrini and fanzago, h. inermis birula and rhipicephalus sanguineus (latreille). study confirmed the strong dominance of all life stages of h. aegyptium among ticks parasitizing we ...200717237970
sero-prevalence and risk indicators for canine ehrlichiosis in three rural areas of brazil.ehrlichia canis has a worldwide geographic distribution, occurring particularly in tropical and subtropical areas. in brazil, the main vector in urban areas is believed to be the brown dog tick rhipicephalus sanguineus, but little is known about the occurrence, transmission and other epidemiological aspects of canine ehrlichiosis in rural areas, where amblyomma ticks are found more frequently than r. sanguineus. a sero-prevalence study of canine ehrlichiosis was carried out in three distinct rur ...200717204439
man-threatening viruses isolated from ticks in saudi arabia.to determine tick viruses transmissible to man in saudi arabia.200718060218
gene silencing of the tick protective antigens, bm86, bm91 and subolesin, in the one-host tick boophilus microplus by rna interference.the use of rna interference (rnai) to assess gene function has been demonstrated in several three-host tick species but adaptation of rnai to the one-host tick, boophilus microplus, has not been reported. we evaluated the application of rnai in b. microplus and the effect of gene silencing on three tick-protective antigens: bm86, bm91 and subolesin. gene-specific double-stranded (dsrna) was injected into two tick stages, freshly molted unfed and engorged females, and specific gene silencing was ...200717196597
highly prevalent coxiella sp. bacterium in the tick vector amblyomma americanum.laboratory-reared and field-collected amblyomma americanum ticks were hosts of a coxiella sp. and a rickettsia sp. while the coxiella sp. was detected in 50 of 50 field-collected ticks, the rickettsia sp. was absent from 32% of ticks. the coxiella sp. showed evidence of a reduced genome and may be an obligate endosymbiont.200717085709
identification of rickettsial isolates at the species level using multi-spacer typing.in order to estimate whether multi-spacer typing (mst), based on the sequencing of variable intergenic spacers, could serve for the identification of rickettsia at the species level, we applied it to 108 rickettsial isolates or arthropod amplicons that include representatives of 23 valid rickettsia species.200717662158
detection of "rickettsia sp. strain uilenbergi" and "rickettsia sp. strain davousti" in amblyomma tholloni ticks from elephants in africa.to date, 6 tick-borne rickettsiae pathogenic for humans are known to occur in africa and 4 of them were first identified in ticks before being recognized as human pathogens.200717683629
animal babesiosis: an emerging zoonosis also in italy?in italy, babesiosis is widespread in several central and southern regions, but few data are available on its presence in most italian areas. in 2004 a project was financed by the miur to investigate on the babesiosis epidemiology in vertebrate and invertebrate hosts, and on the transmission risk for humans in central and northern regions of the country. microscopy and/or molecular tools were applied to blood samples of wild animals, livestock and pets, and to 1,677 ticks collected on animals or ...200717691605
anaphylactic shock caused by tick (rhipicephalus sanguineous). 200717694706
localization and visualization of a coxiella-type symbiont within the lone star tick, amblyomma americanum.a coxiella-type microbe occurs at 100% frequency in all amblyomma americanum ticks thus far tested. using laboratory-reared ticks free of other microbes, we identified the amblyomma-associated coxiella microbe in several types of tissue and at various stages of the life cycle of a. americanum by 16s rrna gene sequencing and diagnostic pcr. we visualized amblyomma-associated coxiella through the use of a diagnostic fluorescence in situ hybridization (fish) assay supplemented with pcr-based detect ...200717720830
rickettsia conorii israeli tick typhus strain isolated from rhipicephalus sanguineus ticks in portugal.this report describes the first establishment of five isolates of r. conorii israeli tick typhus (itt) strain from rhipicephalus sanguineus ticks in different regions of portugal. ticks were collected on two separate expeditions that took place in bragança, montesinho natural park, and portalegre city.200717767403
screening dogs in ontario for borrelia burgdorferi and ehrlichia canis should be selective rather than routine. 200717824154
tick fauna from two locations in the brazilian savannah.the cerrado is brazil's tropical savannah, which is arguably under greater threat than the amazon rainforest. the cerrado biome of tropical south america covers about 2 million km(2) and is considered a biodiversity hot spot which means that it is especially rich in endemic species and particularly threatened by human activities. the cerrado is increasingly exposed to agricultural activities which enhance the likelihood of mixing parasites from rural, urban and wildlife areas. information about ...200717828441
movement of rhipicephalus sanguineus adults between co-housed dogs during active feeding.adult male ticks have been shown capable of experimental acquisition and transmission of tick-borne pathogens without requiring a molt. to determine the ecological relevance of this intrastadial transmission route, we evaluated the extent to which actively feeding male rhipicephalus sanguineus move naturally between co-housed infested dogs. dogs (n=4) were infested with single color-coded ticks, individually housed in tick-confinement cages for 48 h while infestations established, and then each ...200717904292
life cycles of seven ixodid tick species (acari: ixodidae) under standardized laboratory conditions.studies of transmission, maintenance, infectivity, virulence, and pathogenicity of tick-borne agents require the use of large numbers of live laboratory-raised ticks. colonies of ixodes scapularis say, ixodes pacificus cooley & kohls, amblyomma americanum (l.), dermacentor occidentalis marx, dermacentor variabilis (say), hemaphysalis leporispalustris (packard), and rhipicephalus sanguineus (latrielle) have been maintained in our laboratory at the centers for disease control and prevention for fi ...200717915502
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 ...200717916642
confirmation of the efficacy of a novel formulation of metaflumizone plus amitraz for the treatment and control of fleas and ticks on dogs.a novel spot-on formulation containing metaflumizone plus amitraz (promeris/promeris duo for dogs, fort dodge animal health, overland park, ks) was evaluated in four laboratory studies to confirm efficacy against fleas and ticks on dogs for 1 month. three different strains of cat flea (ctenocephalides felis felis) and four tick species were used. rhipicephalus sanguineus and dermacentor variabilis were evaluated concurrently in two studies and ixodes scapularis and amblyomma americanum in one st ...200717923330
dose determination of a novel formulation of metaflumizone plus amitraz for control of cat fleas (ctenocephalides felis felis) and brown dog ticks (rhipicephalus sanguineus) on dogs.a novel spot-on formulation containing metaflumizone and amitraz (promeris/promeris duo for dogs, fort dodge animal health, overland park, ks) was evaluated in a laboratory study to determine the appropriate dose for efficacy against fleas and ticks on dogs for 1 month. thirty-six beagles were randomly allocated to six equal groups and individually housed. one group remained nontreated. another was treated with a placebo formulation (solvents with no active ingredients). three groups of dogs wer ...200717931781
ticks and associated pathogens collected from domestic animals in the netherlands.following an outbreak of autochthonous canine babesiosis in the netherlands, a request made to veterinarians and the public to collect ticks from companion animals resulted in 4298 ticks submitted between july 2005 and october 2006 to our center. ticks were identified as ixodes ricinus adults (2907/4298, 67.6%), ixodes sp. nymphs (529/4298, 12.3%) and ixodes sp. larvae (385/4298, 9.0%), i. hexagonus adults (328/4298, 7.6%), dermacentor reticulatus (72/4298, 1.7%), and several other exotic tick s ...200717979540
[a descriptive epidemiological study on canine babesiosis in the lake geneva region].a descriptive study was carried out in the district of the lake geneva between march 1, 2005 and august 31,2006 to assess the incidence and prevalence of canine babesiosis, to genotype the babesia species occurring, to assess the most frequently clinical signs found and to address the potential of autochthonous transmission. this included a data assessment on the different tick-populations occurring in the area and on the prevalence of babesia-dna in these ticks. a total of 56 veterinary practic ...200717983018
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 ...200718094887
experimental infection of dairy calves with ehrlichia chaffeensis.human monocytic ehrlichiosis (hme) is a zoonotic emerging tick-borne disease with clinical signs that range from mild symptoms to multiple organ failure and death. ehrlichia chaffeensis, the aetiologic agent of hme, is reported to infect a divergent range of mammals. although cattle are common hosts of the primary vector of this pathogen, the susceptibility of this host to e. chaffeensis has not been reported to date. this study was undertaken to determine if cattle could provide a useful infect ...200718033836
outbreak of canine monocytic ehrlichiosis in saudi arabia.canine monocytic ehrlichiosis (cme) is a widespread tickborne infection of canids caused by ehrlichia canis, a gram-negative obligatory intracellular bacteria belonging to the family anaplasmataceae. cme is reported to have worldwide distribution, but its presence in a region requires the presence of the vector, the brown dog tick rhipicephalus sanguineus.200718041697
prevalence of ixodid ticks on cattle in mazandaran province, iran.a survey was carried out to investigate the prevalence of hard tick species (acari: ixodidae) on cattle in mazandaran province, iran. a total of 953 ticks were collected from 86 infested cattle during activating seasons of ticks during 2004-2005. nine species were identified: boophilus annulatus (51.3%), rhipicephalus bursa (16.8%), haemaphysalis punctata (6.3%), ixodes ricinus (6.8%), hyalomma marginatum (12.5%), hyalomma anatolicum excavatum (5.2%), hyalomma asiaticum (0.6%), hyalomma detritum ...200718165714
anaplasma platys in dogs, chile.we conducted a 16s rrna nested pcr for the genus ehrlichia and ehrlichia spp. with blood samples from 30 ill dogs in chile. phylogenetic analysis was performed by using groesl gene amplification. we identified anaplasma platys as 1 of the etiologic agents of canine ehrlichiosis.200718252119
rickettsia monacensis and human disease, spain.we identified rickettsia monacensis as a cause of acute tickborne rickettsiosis in 2 humans. its pathogenic role was assessed by culture and detection of the organism in patients' blood samples. this finding increases the number of recognized human rickettsial pathogens and expands the known geographic distribution of mediterranean spotted fever-like cases.200718252123
[influence of aggregation on the molting process of rhipicephalus sanguineus, (latreille, 1806) (acari: ixodidae) under laboratory conditions].the objective of this experiment was to evaluate the influence of different aggregations on the molting process of rhipicephalus sanguineus (latreille, 1806). tick-naïve domestic rabbits (oryctolagus cuniculus) were used as experimental hosts for the parasitic phase. a total of 10 rabbits were used on the experiment. all tick free-living phases were kept in incubator at 27+/-1 degrees c, 80+/-5% relative humidity and scotophase. the periods of pre-molt, molt, percentage of ecdisis and molt rhyth ...200718373896
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.200718214179
epidemiological features of mediterranean spotted fever, murine typhus, and q fever in split-dalmatia county (croatia), 1982-2002.we determined the epidemiological features of three zoonoses in hospitalized patients in southern croatia. patients were diagnosed by serological testing. clinical and epidemiological data were also collected. between 1982 and 2002, mediterranean spotted fever (msf) was diagnosed in 126 (incidence rate 1.27/100,000 per year), murine typhus (mt), in 57 (incidence rate 0.57/100,000 per year), and q fever in 170 (incidence rate 1.7/100,000 per year) patients. msf and q fever were characterized by a ...200717850690
in vitro isolation and molecular characterization of an ehrlichia canis strain from são paulo, brazil.an ehrlichia canis isolate was obtained from an naturally infected dog exhibiting clinical signs of ehrlichiosis in são paulo municipality, state of são paulo, brazil. the isolate was characterized by pcr and dna sequencing of portions of the ehrlichial genes dsb, 16srrna, and p28. partial dsb and 16s rrna sequences were identical to three and five other e. canis strains, respectively, from different countries and continents (including north america, africa, asia and europe). conversely, the p28 ...200824031251
detection and molecular characterization of babesia canis vogeli from naturally infected dogs and rhipicephalus sanguineus ticks in tunisia.canine babesiosis, caused by intra-erythrocytic babesia, is a tick-borne disease of worldwide importance. no information on canine babesiosis has been documented in tunisia. detection and analysis of babesia species from naturally infected dogs and ticks recovered from dogs were attempted by reverse line blot hybridization and nucleotide sequence analysis based on 18s rrna gene. out of 180 blood samples collected from domestic dogs in 4 villages situated in different bioclimatic zones, 12 were p ...200818242865
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 ...200818847319
mediterranean spotted fever.rickettsial disease has recently undergone an important evolution, particularly in the field of molecular genetics. this development includes mediterranean spotted fever (msf), a tick-borne disease caused by rickettsia conorii. important changes have occurred in ecologic and epidemiologic comprehension of the disease, and in the occurrence of severe forms. however, many questions still remain, including the identity of the real vector and reservoir of r conorii, and whether other risk factors ex ...200818755388
questions on mediterranean spotted fever a century after its discovery.mediterranean spotted fever (msf) was first described in 1910. twenty years later, it was recognized as a rickettsial disease transmitted by the brown dog tick. in contrast to rocky mountain spotted fever (rmsf), msf was thought to be a benign disease; however, the first severe case that resulted in death was reported in france in the 1980s. we have noted important changes in the epidemiology of msf in the last 10 years, with emergence and reemergence of msf in several countries. advanced molecu ...200818760001
absence of wolbachia endobacteria in the non-filariid nematodes angiostrongylus cantonensis and a. costaricensis.abstract: the majority of filarial nematodes harbour wolbachia endobacteria, including the major pathogenic species in humans, onchocerca volvulus, brugia malayi and wuchereria bancrofti. these obligate endosymbionts have never been demonstrated unequivocally in any non-filariid nematode. however, a recent report described the detection by pcr of wolbachia in the metastrongylid nematode, angiostrongylus cantonensis (rat lungworm), a leading cause of eosinophilic meningitis in humans. to address ...200818801163
warmer weather linked to tick attack and emergence of severe rickettsioses.the impact of climate on the vector behaviour of the worldwide dog tick rhipicephalus sanguineus is a cause of concern. this tick is a vector for life-threatening organisms including rickettsia rickettsii, the agent of rocky mountain spotted fever, r. conorii, the agent of mediterranean spotted fever, and the ubiquitous emerging pathogen r. massiliae. a focus of spotted fever was investigated in france in may 2007. blood and tissue samples from two patients were tested. an entomological survey w ...200819015724
laboratory maintenance of rickettsia rickettsii.this unit includes protocols for the laboratory maintenance of the obligate intracellular bacterium rickettsia rickettsii, including propagation in mammalian cell cultures, as well as isolation, counting, and storage procedures. regulations for working with r. rickettsii in biosafety level 3 containment are also discussed.200819016440
exploring the mialome of ticks: an annotated catalogue of midgut transcripts from the hard tick, dermacentor variabilis (acari: ixodidae).ticks are obligate blood feeders. the midgut is the first major region of the body where blood and microbes ingested with the blood meal come in contact with the tick's internal tissues. little is known about protein expression in the digestive tract of ticks. in this study, for analysis of global gene expression during tick attachment and feeding, we generated and sequenced 1,679 random transcripts (ests) from cdna libraries from the midguts of female ticks at varying stages of feeding.200819021911
defining the immune response to ehrlichia species using murine models.pathogenic bacteria belonging to the family anaplasmataceae include species of the genera ehrlichia and anaplasma. ehrlichia chaffeensis, first known as the causative agent of human monocytic ehrlichiosis, also infects several vertebrate hosts including white-tailed deer, dogs, coyotes and goats. e. chaffeensis is transmitted from the bite of an infected hard tick, such as amblyomma americanum. e. chaffeensis and other tick-transmitted pathogens have adapted to both the tick and vertebrate host ...200819028013
a review of the off-label use of selamectin (stronghold/revolution) in dogs and cats.since its introduction approximately seven years ago, selamectin (stronghold/revolution, pfizer inc.) has been used off-label to treat a number of ecto- and endoparasite conditions in dogs and cats. it has been used as a successful prophylactic against dirofilaria repens and as a treatment for aelurostrongylus abstrusus in cats. it has also been used to treat notoedric mange, infestation with the nasal mite pneumonyssoides caninum, cheyletiella spp. and neotrombicula autumnalis infestations and ...200819032763
first direct detection of rickettsial pathogens and a new rickettsia, 'candidatus rickettsia barbariae', in ticks from sardinia, italy.the present study evaluated the molecular detection and identification of rickettsia species in 83 ticks collected in sardinia, italy. fifteen ticks were pcr-positive using glta-specific and ompa-specific primers, leading to the identification of rickettsia aeschlimannii in hyalomma marginatum marginatum, r. massiliae in rhipicephalus turanicus and in rhipicephalus sanguineus, and a new rickettsia, previously referred to as potirb169 in portugal, in four rhipicephalus turanicus. this new species ...200819040474
fatal case of israeli spotted fever after mediterranean cruise. 200819046528
comparative susceptibility of larval stages of amblyomma aureolatum, amblyomma cajennense, and rhipicephalus sanguineus to infection by rickettsia rickettsii.the current study compared the susceptibility of larval stages of amblyomma cajennense (f.), amblyomma aureolatum (pallas), and rhipicephalus sanguineus (latreille) to infection by a brazilian strain of rickettsia rickettsii. guinea pigs experimentally infected by r. rickettsii were simultaneously infested by larvae of the three tick species. recovered engorged larvae were allowed to molt to nymphs and held in an incubator at 23 degrees c and 85-90% rh. subsequent flat nymphs were tested for ric ...200819058642
parasites of importance for human health in nigerian dogs: high prevalence and limited knowledge of pet owners.dogs are the most common pet animals worldwide. they may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. in nigeria, epidemiological knowledge on these parasites is limited.200819068110
taxonomical studies of ticks infesting wild rodents from asir province in saudi arabia.ticks infesting rodents in asir province, which is about 3000 meter above sea level, were surveyed in wadi dalaghan and wadi bin hachbal. they were examined from september to december 2006, where ten local life baited traps were distributed for 3 days each month. the rodents were acomys c. dimitatus (20), meriones rex (19) & one gerbillus cheesmani. fifty three nymphs were dropped off from the rodents in the laboratory 3 to 12 days post-trapping. forty eight nymphs were reared to adults for iden ...200819143116
[mediterranean spotted fever due to contact with dog-tick].mediterranean spotted fever (msf) is one of the tick-borne rickettsial infections caused by rickettsia conorii. it is transmitted to humans by brown dog ticks (rhipicephalus sanguineus). in this case report, a 16-years-old male patient who was diagnosed as msf after an exposure to dog-tick in bartin province (located at middle black sea region of turkey) has been presented. his history revealed that, five days before admission to the hospital (on june, 2007) he had cleaned dog-ticks from his dog ...200819149095
fungal formulations to control rhipicephalus sanguineus engorged females.entomopathogenic fungi are promising alternatives to chemical acaricides in controlling tick populations; however, biological formulations are required to improve conidial performance of these pathogens in the field. this study evaluated the effect of in vitro treatment of rhipicephalus sanguineus with conidial formulations of beauveria bassiana (bb) or metarhizium anisopliae (ma). conidia were formulated (at 10(8) conidia ml(-1)) in (1) emulsifiable concentrate (ec), (2) polymerized cellulose g ...200819120220
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