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reliminary survey of ticks (acari: ixodidae) on cattle in central equatoria state, southern sudan.in a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in central equatoria state, southern sudan was determined. three locations were selected (gumbo, khor rumla and nyaing) and surveyed every 3 months. two cattle herds in each of the three locations were visited four times during the study period. total body collections of ticks were made from each of five cattle (nilotic zebu breed) kept in six different herds. four tick genera and ten spe ...200818575063
distribution, hosts, 16s rdna sequences and phylogenetic position of the neotropical tick amblyomma parvum (acari: ixodidae).the hosts, distribution, intraspecific genetic variation and phylogenetic position of amblyomma parvum (acari: ixodidae) have recently been re-assessed. data on this tick's hosts and distribution were obtained not only from existing literature but also from unpublished records. sequences of the ticks' mitochondrial 16s ribosomal dna (rdna) were used to evaluate genetic variation among specimens of a. parvum from different localities in argentina and brazil, and to explore the phylogenetic relati ...200818577332
failure of ivermectin and eprinomectin to control amblyomma parvum in goats: characterization of acaricidal activity and drug pharmacokinetic disposition.the therapeutic efficacies of ivermectin (subcutaneous injection) and eprinomectin (topical treatment) given at two different dosage levels to goats naturally infested with amblyomma parvum were assessed. treatments included subcutaneous injection of ivermectin at 0.2 and 0.4mg/kg and extra-label pour-on administration of eprinomectin at 0.5 and 1mg/kgb.w. ivermectin and eprinomectin failed to control amblyomma parvum on goats. treatment with ivermectin resulted in a low number of engorged femal ...200818584966
aspects of the life cycle of amblyomma parvum (acari: ixodidae) under natural conditions.monthly samplings of the rodent galea musteloides (caviidae) were carried out from january 2005 to december 2006 in quilino, córdoba province, argentina, to determine the seasonal distribution of immature stages of amblyomma parvum. in the same locality, cattle and goats were also monthly examined to asses the seasonality of the females of this species. engorged ticks collected on their natural hosts were maintained in the laboratory at 25 degrees c and 83-86% relative humidity to study biologic ...200818620813
permeability of tarsal sensilla in the tick amblyomma americanum l. (acarina, ixodidae).ticks were submerged in silver-protein solution, prior to fixation for electron microscopy, in order to trace the pathway of molecules in supposed tarsal chemoreceptors. sensilla with radially arranged cuticular canals (100-200 a in diameter) leading to the centrally located dendrites show silver granules inside the canals and in the central lumen, thus directly making contact with the dendrites. sensilla with large, plugged pores (1200 a) exhibit an accumulation of silver granules in the pore o ...197218631584
effect of 20-hydroxyecdysone and haemolymph on oogenesis in the ixodid tick amblyomma hebraeum.earlier work from our laboratory indicated that injection of 20-hydroxyecdysone (20e) into non-vitellogenic female amblyomma hebraeum ticks stimulates the synthesis of vitellogenin (vg), but not its uptake into oocytes [friesen, k., kaufman, w.r., 2004. effects of 20-hydroxyecdysone and other hormones on egg development, and identification of a vitellin-binding protein in the ovary of the tick, amblyomma hebraeum. journal of insect physiology 50, 519-529]. in contrast, thompson et al. [thompson, ...200818634796
acute dermatitis caused by amblyomma variegatum larvae on chickens.acute dermatitis caused by amblyomma variegatum larvae infestation was observed in adult local nigerian chickens. skin lesions containing numerous a. variegatum larvae were observed on gross examination. histopathology showed skin haemorrhages, larvae, necrosis and infiltration of eosinophils. it was suspected that the free range life of the birds could have predisposed them to the infestation.199018679988
identification of residual blood proteins in ticks by mass spectrometry proteomics.mass spectrometry-based proteomics of individual ticks demonstrated persistence of mammalian host blood components, including alpha- and beta-globin chains, histones, and mitochondrial enzymes, in ixodes scapularis and amblyomma americanum ticks for months after molting. residual host proteins may identify sources of infection for ticks.200818680654
morphological changes in the salivary glands of amblyomma cajennense females (acari: ixodidae) in different feeding stages on rabbits at first infestation.this study examined salivary glands of unfed, partially engorged, and engorged females of the tick amblyomma cajennense on rabbits at first infestation using histological and histochemical techniques. in type i acini, no significant changes were observed among the three feeding conditions. in type ii acini of unfed females, c1, c2, and c4 cells were described for the first time in this species. in a comparison among the three feeding conditions, an increase in this acinus was observed, due to th ...200818685958
the effects of vegetation density and habitat disturbance on the spatial distribution of ixodid ticks (acari: ixodidae).larval, nymphal, and adult amblyomma americanum (l.), and adult dermacentor variabilis (say) ticks were collected using timed dragging techniques, in an attempt to examine how different habitat variables affect models that describe the distribution of ticks in virginia, usa. tick count data were modeled using two approaches: (i) habitat and edge, and (ii) habitat, edge, vegetation density and levels of disturbance. nymphs and adults tended to follow a forest edge distribution when analysed by ha ...200818686272
molecular and morphological description of a hepatozoon species in reptiles and their ticks in the northern territory, australia.ticks, representing 3 species of amblyomma, were collected from the water python (liasis fuscus) and 3 additional reptile species in the northern territory, australia, and tested for the presence of hepatozoon sp., the most common blood parasites of snakes. in addition, blood smears were collected from 5 reptiles, including the water python, and examined for the presence of the parasite. hepatozoon sp. dna was detected in all tick and reptile species, with 57.7% of tick samples (n = 187) and 35. ...200918710299
ticks (acari: ixodidae) infesting wild birds in an atlantic forest area in the state of são paulo, brazil, with isolation of rickettsia from the tick amblyomma longirostre.during field work in nazaré paulista, state of são paulo, brazil, we found 13 (56.5%) of 23 birds (mostly passeriformes) to be infested by 28 larvae and 1 nymph of amblyomma spp. two larvae were reared to the adult stage, being taxonomically identified as amblyomma parkeri fonseca and aragio, whereas five larvae and one nymph were identified as amblyomma longirostre koch. all six a. longirostre specimens were shown to be infected by rickettsia, as demonstrated by polymerase chain reaction (pcr) ...200818714882
canine babesiosis caused by babesia canis vogeli in rural areas of the state of minas gerais, brazil and factors associated with its seroprevalence.this epidemiological survey on canine babesiosis was carried out in three distinct rural regions (lavras, belo horizonte and nanuque) of the state of minas gerais, brazil. ticks and blood samples were collected during a dry season (lavras, n=92; belo horizonte, n=50; nanuque, n=102) and the subsequent rainy season (lavras, n=71; belo horizonte, n=28; nanuque, n=66) from dogs living on farms. plasma samples were analyzed by the indirect fluorescent antibody test for detection of anti-babesia cani ...200918723199
laboratory maintenance of ehrlichia chaffeensis and ehrlichia canis and recovery of organisms for molecular biology and proteomics studies.tick-borne illnesses are emerging as a major concern for human health in recent years. these include the human monocytic ehrlichiosis caused by the amblyomma americanum tick-transmitted bacterium, ehrlichia chaffeensis; human ewingii ehrlichiosis caused by ehrlichia ewingii (also transmitted by a. americanum ticks); and human granulocytic anaplasmosis caused by the ixodes scapularis tick-transmitted pathogen, anaplasma phagocytophilum. likewise, tick-borne rickettsial pathogens are also a major ...200818770537
rickettsia parkeri rickettsiosis and its clinical distinction from rocky mountain spotted fever.rickettsia parkeri rickettsiosis, a recently identified spotted fever transmitted by the gulf coast tick (amblyomma maculatum), was first described in 2004. we summarize the clinical and epidemiological features of 12 patients in the united states with confirmed or probable disease attributable to r. parkeri and comment on distinctions between r. parkeri rickettsiosis and other united states rickettsioses.200818808353
exotic grass invasion reduces survival of amblyomma americanum and dermacentor variabilis ticks (acari: ixodidae).exotic plants often invade areas of high human activity, such as along trails, roads, and forest edges, and in disturbed riparian areas. these same habitat types are also favored by ticks. this convergence suggests that habitat modifications caused by exotic plant invasions may mediate disease vector habitat quality, indirectly affecting human disease risk at the local spatial scale. we tested the hypothesis that experimental invasions of japanese stiltgrass, microstegium vimineum (trin.) a. cam ...200818826028
the impact of rna interference of the subolesin and voraxin genes in male amblyomma hebraeum (acari: ixodidae) on female engorgement and oviposition.reducing or replacing the use of chemical pesticides for tick control is a desirable goal. the most promising approach would be to develop vaccines that protect hosts against tick infestation. antigens suitable for the development of anti-tick vaccines will likely be those essential for vital physiological processes, and in particular those directly involved in feeding and reproduction. in this study genes from amblyomma hebraeum koch that encode for subolesin and voraxin were studied in male ti ...200918830675
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
molecular and biological characterization of the amblyomma americanum organic anion transporter polypeptide.the organic anion transporting polypeptides (oatps in rodents and other organism; oatps in human) are na(+)-independent transporters that shuttle a wide range of endogenous and xenobotic amphipathic compounds across plasma membranes. we previously discovered an amblyomma americanum tick (aam) oatp cdna among genes that were upregulated or induced in ticks that were stimulated to start feeding. in this study, we have characterized a 2860 bp full-length cdna that encode a 724 amino acid putative p ...200818931313
experimental infection of opossums didelphis aurita by rickettsia rickettsii and evaluation of the transmission of the infection to ticks amblyomma cajennense.the present study evaluated the infection of opossums (didelphis aurita) by rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of r. rickettsii to amblyomma cajennense ticks. three groups of opossums were evaluated: on day 0, group 1 (g1) was inoculated intraperitoneally with r. rickettsii; group 2 (g2) was infested by r. rickettsii-infected ticks; and group 3 (g3) was the uninfected control group. opossum rectal temperature was measured daily. blood samples were ...200818945194
rickettsial spotted fever in capoeirão village, itabira, minas gerais, brazil.the present study investigated the infection by spotted fever rickettsia in an endemic area for brazilian spotted fever (bsf; caused by rickettsia rickettsii) in minas gerais state, brazil. human, canine and equine sera samples, and amblyomma cajennense adult ticks collected in a rural area of itabira city, minas gerais state were tested for rickettsial infection. through immunofluorescence assay (ifa) we demonstrated the presence of antibodies anti-r. rickettsii in 8.2%, 81.3% and 100% of the h ...200818949349
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
fat body cells of amblyomma cajennense partially engorged females (acari: ixodidae) and their role on vitellogenesis process.during the process of arthropoda reproduction, the synthesis and uptake of proteins, carbohydrates, and lipids by oocytes is termed vitellogenesis. these compounds that will make up the yolk may be in ticks endogenously synthesized by the oocytes and/or exogenously produced by the fat body and pedicel cells. this study examined the fat body of amblyomma cajennense ticks at the cytochemical ultrastructural level to demonstrate the presence of lipids, proteins and carbohydrates in trophocytes. the ...200919041306
rickettsia parkeri in argentina.clinical reports of an eschar-associated rickettsiosis in the paraná river delta of argentina prompted an evaluation of amblyomma triste ticks in this region. when evaluated by pcr, 17 (7.6%) of 223 questing adult a. triste ticks, collected from 2 sites in the lower paraná river delta, contained dna of rickettsia parkeri.200819046514
molecular detection of ehrlichia chaffeensis in amblyomma parvum ticks, argentina. 200819046533
role of the lone star tick, amblyomma americanum (l.), in human and animal diseases.we reviewed scientific literature pertaining to known and putative disease agents associated with the lone star tick, amblyomma americanum. reports in the literature concerning the role of the lone star tick in the transmission of pathogens of human and animal diseases have sometimes been unclear and even contradictory. this overview has indicated that a. americanum is involved in the ecology of several disease agents of humans and other animals, and the role of this tick as a vector of these di ...200919054615
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
survey of tick infestation in small ruminants of miesso district, west harergie, oromia region, ethiopia.a survey was conducted to identify tick species and determine the prevalence of tick infestation in small ruminants of miesso district, west harergie zone. collection and identification of the ticks were undertaken from november 2007 to april 2008. all visible individual adult ticks were collected from the body of 328 goats and 40 sheep. the prevalence of tick infestation in goats and sheep was found to be 89.9% and 87.5%, respectively. in this study, ten species of ticks which grouped under fou ...200919082757
the use of a semiochemical bait to enhance exposure of amblyomma variegatum (acari: ixodidae) to metarhizium anisopliae (ascomycota: hypocreales).experiments were conducted to explore the use of a semiochemical bait to enhance exposure of amblyomma variegatum fabricius (acari: ixodidae) to different formulations of the entomopathogenic fungus metarhizium anisopliae (metsch.) sorok. (ascomycota: hypocreales). initially, the relative efficacies of attraction-aggregation-attachment pheromone (aaap), made up of o-nitrophenol, methyl salicylate and nonanoic acid in the ratio 2:1:8, 1-octen-3-ol and butyric acid, were evaluated in an olfactomet ...200919091474
amblyomma americanum (l): tick macrophage migration inhibitory factor peptide immunization lengthens lone star tick feeding intervals in vivo.immunizations of new zealand white rabbits with specific macrophage migration inhibitory factor (mif) tick peptide (pep) produced circulating anti-tick pep antibodies in the hosts. antibody titers of greater than 1:5000 to tick mif peptide were observed for crude sera from pep-immunized rabbits. pep- and bsa-vaccinated rabbits were infested with amblyomma americanum adults. feeding intervals, female weights, egg masses and percent egg hatch were measured for ticks feeding on control and immunize ...200919111543
amblyomma variegatum ticks and heartwater on three caribbean islands.amblyomma variegatum tick infestation, tick infection by ehrlichia ruminantium (er), and er genetic diversity were studied in the caribbean islands of guadeloupe, marie-galante, and antigua between 2003 and 2005. nested pcr for pcs20 was used to detect er, while er strains were characterized by sequencing or by restriction fragment length polymorphism (rflp) profiles of map-1 pcr products. in 2003 in guadeloupe, the prevalence of tick-infested herds was 35.6%. in marie-galante 79.1% of herds in ...200819120208
field collection and genetic classification of tick-borne rickettsiae and rickettsiae-like pathogens from south texas: coxiella burnetii isolated from field-collected amblyomma cajennense.we are reporting the first known isolation of the q-fever agent coxiella burnetii from field-collected cayenne ticks amblyomma cajennense in north america. q-fever affects a number of domestic ungulates where it can lead to abortion in sheep and goats. there is far less known about the disease's effects on wild species, primarily because of the tendency of the disease to self resolve and to provide long-term immunity to subsequent infections. the first recovery of c. burnetii in north america wa ...200819120212
cutaneous basophilia in the resistance of goats to amblyomma cajennense nymphs after repeated infestations.the acquisition of resistance in goats against amblyomma cajennense after repeated infestations and the role of inflammatory cells in this mechanism were investigated. ten naive goats aged 6 months were distributed into two groups: test (n= 5), infested thrice at 30-day intervals; and control (n= 5), infested once. nymphs (n= 115 per animal per infestation) were released inside alimentary chambers glued to the animal's dorsum and the following biological parameters were evaluated: yielding rate, ...200819120216
guinea pigs develop cutaneous basophilia after repeated infestations by nymphs of the tick amblyomma triste.this study investigated the development of resistance in guinea pigs to nymphs of amblyomma triste ticks after repeated infestations. guinea pigs were infested thrice, at 30-day intervals, with 30 nymphs of a. triste per animal per infestation. acquisition of resistance was evaluated by determining: nymph yielding rate, engorgement period, and weight. skin biopsies of tick bite sites were collected at 24, 48, and 96 h after tick attachment for inflammatory cell counts. engorged nymphs weighed 5. ...200819120217
effect of amblyomma cajennense ticks on the immune response of balb/c mice and horses.this work evaluated the effect of the amblyomma cajennense tick on the immune response of balb/c mice and on horse lymph node cell proliferation. we observed that mice do not develop resistance to nymphs of this tick species and that lymphocyte proliferation of this host is inhibited by tick saliva, nymphal extract, or infestations. horse lymph node cell proliferation is inhibited by tick saliva as well. mice lymphocytes under the effect of tick saliva, nymphal extract, or infestations display a ...200819120218
viral association with the elusive rickettsia of viper plague from ghana, west africa.we previously reported a rickettsial heartwater-like disease in vipers from ghana that resembled heartwater in its gross lesions, was apparently transmitted by ticks (aponomma and amblyomma), and responded clinically favorably to early treatment with tetracycline. cell culture showed consistent cytopathic effects in bovine endothelial cells, viper cells, and mouse cells, and inhibition of cytopathic effect by tetracycline in vitro. a type d retrovirus was observed in vacuoles in all infected cel ...200819120239
seasonal and spatial dynamics of ectoparasite infestation of a threatened reptile, the tuatara (sphenodon punctatus).the conservation of threatened vertebrate species and their threatened parasites requires an understanding of the factors influencing their distribution and dynamics. this is particularly important for species maintained in conservation reserves at high densities, where increased contact among hosts could lead to increased rates of parasitism. the tuatara (sphenodon punctatus) (reptilia: sphenodontia) is a threatened reptile that persists at high densities in forests (approximately 2700 tuatara/ ...200819120965
unique biological rhythm in the reproductive behaviour of female ticks of reptiles.we report the discovery of a biological rhythm in the reproductive behaviour of the tick bothriocroton hydrosauri that was absent in amblyomma limbatum, a species that occurs on the same species of reptile host. female b. hydrosauri mated in autumn or winter delayed oviposition until the following spring, while there was no diapause in conspecific females mated in spring or early summer. initiation of ovipositional diapause in ticks is usually related to photoperiodic stimuli, but this was not t ...200919126271
biology and life cycle of amblyomma incisum (acari: ixodidae).amblyomma incisum neumann is a major tick species in the atlantic forest of brazil. tapir is the main host for adult ticks and a high aggressiveness of nymphs to humans has been reported. in this work data on the biology and life cycle of this tick species is presented for the first time. it was shown that horse is a suitable host for a. incisum adults and rabbit for larvae and nymphs. it was also shown that a. incisum is a big tick species (mean engorged female weight of 1.96 g) with a long lif ...200919130270
efficacy of the new repellent bioud against three species of ixodid ticks.bioud with the active ingredient 2-undecanone originally derived from wild tomato plants is a new repellent recently registered by the us epa. repellent efficacy of bioud (7.75% 2-undecanone) and deet (98.11%) was examined in the laboratory using a choice test between repellent-treated and control filter paper surfaces for amblyomma americanum, dermacentor variabilis, and ixodes scapularis. bioud provided greater repellency against a. americanum and i. scapularis than deet. no difference was fou ...200919140016
experimental infection of capybaras hydrochoerus hydrochaeris by rickettsia rickettsii and evaluation of the transmission of the infection to ticks amblyomma cajennense.the present study evaluated the infection of capybaras (hydrochoerus hydrochaeris) by rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of r. rickettsii to amblyomma cajennense ticks. two groups of two capybaras each were evaluated: on day 0, group 1 (g1) was infested by r. rickettsii-infected ticks, and group 2 (g2) was inoculated intraperitoneally with r. rickettsii. two additional groups were control groups, not exposed to r. rickettsii, being cg1 group the c ...200919147293
transmission of cytauxzoon felis to a domestic cat by amblyomma americanum.cytauxzoon felis was transmitted to a domestic cat by amblyomma americanum. the infection was produced by the bite of a. americanum adults that were acquisition fed as nymphs on a domestic cat that naturally survived infection of c. felis. fever, inappetence, depression, and lethargy were first noted 11 days post-infestation (dpi). pale mucus membranes, splenomegaly, icterus, and dyspnea were also observed during the course of the disease. the body temperature of the experimentally infected c. f ...200919168288
comments on controversial tick (acari: ixodida) species names and species described or resurrected from 2003 to 2008.there are numerous discrepancies in recent published lists of the ticks of the world. here we review the controversial names, presenting evidence for or against their validity and excluding some altogether. we also address spelling errors and present a list of 17 species described or resurrected during the years 2003-2008. we consider the following 35 tick species names to be invalid: argas fischeri audouin, 1826, ornithodoros boliviensis kohls and clifford, 1964, ornithodoros steini (schulze, 1 ...200919169832
ecological aspects of the free-living ticks (acari: ixodidae) on animal trails within atlantic rainforest in south-eastern brazil.in a recent ecological study of the ticks on animal trails within an area of atlantic rainforest in south-eastern brazil, amblyomma aureolatum, a. brasiliense, a. incisum, a. ovale and haemaphysalis juxtakochi were found questing on the vegetation. most of the ticks recorded by a small, man-made dam on the forest border were a. dubitatum but a few a. brasiliense and a. cajennense, one a. incisum and one h. juxtakochi were also found. the seasonal activity of the ticks indicated that a. incisum a ...200919173777
kupe virus, a new virus in the family bunyaviridae, genus nairovirus, kenya.we have previously described isolation and preliminary identification of a virus related to dugbe virus (dugv), family bunyaviridae, genus nairovirus. six isolates of the virus were obtained from pools of amblyomma gemma and rhipicephalus pulchellus ticks collected from hides of cattle in nairobi, kenya, in october 1999. we report results of further characterization of this virus, including growth kinetics in cell culture and full-length genome sequencing and genetic characterization, which show ...200919193256
isolongifolenone: a novel sesquiterpene repellent of ticks and mosquitoes.a naturally occurring sesquiterpene, isolongifolenone, derivatives of which have been used extensively as ingredients in the cosmetics industry, was discovered to effectively repel blood-feeding arthropods that are important disease vectors. we show that (-)-isolongifolenone deters the biting of the mosquitoes, aedes aegypti (l.) and anopheles stephensi liston, more effectively than the widely used synthetic chemical repellent, n,n-diethyl-3-methyl benzamide (deet), in laboratory bioassays. the ...200919198523
detection of borrelia burgdorferi and borrelia lonestari in birds in tennessee.lyme disease in the united states is caused by the bacterial spirochete borrelia burgdorferi s.s. (johnson, schmid, hyde, steigerwalt, and brenner), which is transmitted by tick vectors ixodes scapularis (say) and i. pacificus (cooley and kohls). borrelia lonestari, transmitted by the tick amblyomma americanum l., may be associated with a related syndrome, southern tick-associated rash illness (stari). borrelia lonestari sequences, reported primarily in the southeastern states, have also been de ...200919198527
prevalence of anaplasma marginale in different tick species from ngorongoro crater, tanzania.in 2001, ngorongoro crater was infested with high density of ticks on grassland, livestock and wildlife which was also associated with high mortality. adult ticks were collected, identified, processed for nucleic acids extraction and a molecular analysis was performed to determine the range of tick species harboring anaplasma marginale. the real-time pcr was used in the amplification of rickettsia dna in tick pools (n=527) from 11 identified tick species. six tick species were detected with a. m ...200919201099
bovine dermatophilosis, a re-emerging pandemic disease in zimbabwe.to determine the current distribution of bovine dermatophilosis in zimbabwe, participatory rural appraisals were held at 36 locations in six districts. results showed that bovine dermatophilosis is no longer confined to hwange-lupane area, but is now endemic in gokwe, sanyati, kwekwe, and kadoma. virgin outbreaks of the disease were preceded by the appearance of amblyomma variegatum ticks within an area. spreading to new geographical areas (cited above) occurred during the liberation struggle (1 ...200919212820
conservation and immunogenicity of the mosquito ortholog of the tick-protective antigen, subolesin.the control of arthropod vectors of pathogens that affect human and animal health is important for the eradication of vector-borne diseases. the ortholog of the tick-protective antigen, subolesin, was identified in aedes albopictus and found to have conserved epitopes in ticks and mosquitoes. rna interference with the tick and mosquito double-stranded rna in three tick species resulted in significant gene knockdown and decreased tick weight and/or survival. feeding anopheles atroparvus, aedes ca ...200919229557
redescription of the female, description of the male, and several new records of amblyomma parkeri (acari: ixodidae), a south american tick species.the tick amblyomma parkeri fonseca and aragão was described in 1952, based on female and immature ticks collected in the states of são paulo and santa catarina, brazil. thereafter, there has been no further report of a. parkeri, and the male has remained unknown. herein, we examined ticks collected on porcupines from a locality in the state of são paulo. some of the ticks were identified as amblyomma longirostre (koch, 1844), whereas others as a. parkeri, including male specimens, for which we p ...200919241123
infection and replication of bartonella species within a tick cell line.bartonella species are fastidious, gram negative bacteria, some of which are transmitted by arthropod vectors, including fleas, sandflies, and lice. there is very little information regarding the interaction and/or transmission capabilities of bartonella species by ticks. in the present study, we demonstrate successful infection of the amblyomma americanum cell line, aae12, by seven bartonella isolates and three candidatus bartonella species by electron or light microscopy. with the exception of ...200919242658
ixodid ticks infesting domestic goats in communal land areas of zimbabwe.the purpose of this study was to determine the species spectrum of ticks infesting goats owned by resource-limited farmers in the state-owned communal land areas of zimbabwe. ticks were collected from goats at a single locality within each of 5 communal land areas, and a total of 14 ixodid tick species was recovered. the most numerous tick was rhipicephalus evertsi evertsi, which was present in all areas at each sampling, and a rhipicephalus sp. (near r. punctatus), which was most abundant on go ...200819244819
artificial feeding of amblyomma cajennense (acari: ixodidae) fasting females through capillary tube technique.the present study aimed to adjust the artificial feeding technique through capillaries and to verify its influence over the biology of amblyomma cajennense females. five groups of 20 female ticks were formed. females were starved for 45 days and then fed with citrated bovine blood using capillary tubes in different periods of time. females were divided in five experimental groups with 20 individuals each and fed as follows: groups uninterruptedly fed for 12, 24, and 48 hours and groups fed 2 and ...200819245757
tick-borne ehrlichiosis infection in human beings.human monocytic ehrlichiosis is a tick-borne infectious disease transmitted by several tick species, especially amblyomma spp caused by ehrlichia chaffeensis. e. chaffeensis is an obligatory intracellular, tick-transmitted bacterium that is maintained in nature in a cycle involving at least one and perhaps several vertebrate reservoir hosts. two additional ehrlichia spp, anaplasma (formerly ehrlichia) phagocytophila (the agent of human granulocytic ehrlichiosis [hge]) and e. ewingii (a cause of ...200819248653
notes on populational dynamics of amblyomma ticks (acari: ixodidae) in brazil.previous populational dynamics data generated for amblyomma parvum aragão and amblyomma cajennense (fabricius) in argentina and southeastern brazil have indicated that these ticks complete 1 generation per yr, with larvae predominating in autumn, nymphs in winter, and adults mostly during spring and summer. the present study reports populational dynamics data for free-living amblyomma spp. ticks in northern brazil (amazon forest, latitude 10os), and for amblyomma spp. ticks collected on birds in ...200919256723
[characterization of ectoparasites on dogs in the nucleus of urban expansion of juiz de fora, minas gerais, brazil].the present work studied the characterization of ectoparasites on dogs in the nucleus of urban expansion of juiz de fora, minas gerais, brazil. the collections were conducted from july to september 2003, examining 101 dogs of no defined breed. the ectoparasites were collected through visual and tactile inspection of the animals' bodies, and were then placed in bottles with 70 degrees gl ethanol and identified under a stereomicroscope. specimens were clarified and mounted on slides for analysis u ...200819265575
[ticks of genus amblyomma (acari: ixodidae) and their relationship with hosts in endemic area for spotted fever in the state of são paulo].seven species of mammals and 36 of birds were investigated to determine the tick prevalence and intensity of infestation. the study was conducted at the esalq/usp in piracicaba municipality, state of são paulo. it was collected 52 mammals and 158 birds parasitized by 12,418 ticks. adult ticks (n= 7,343) were found on capybaras, while the immature were mainly collected on small mammals and birds. the main hosts for immatures in descending order were opossums (69.1%), capybara (24.4%) and black vu ...200819265580
ticks infesting amphibians and reptiles in pernambuco, northeastern brazil.ticks infesting amphibians and reptiles in the state of pernambuco are reviewed, based on the current literature and new collections recently carried out by the authors. to date, three tick species have been found on amphibians and reptiles in pernambuco. amblyomma fuscum appears to be exclusively associated with boa constrictor, its type host. amblyomma rotundatum has a relatively low host-specificity, being found on toads, snakes, and iguana. amblyomma dissimile has been found on a lizard and ...200819265581
a borreliacidal factor in amblyomma americanum saliva is associated with phospholipase a2 activity.previous work in our laboratory described the in vitro killing of borrelia burgdorferi when co-cultured with saliva from adult amblyomma americanum. borreliacidal activity was not evident using ixodes scapularis saliva. mixing trypsin with saliva eliminated the borreliacidal activity of a. americanum saliva, while incorporating a trypsin inhibitor restored all borreliacidal activity, indicating this factor was of protein or peptide origin. one-dimensional page indicated at least 7 major protein ...200919271281
transcriptome analysis of the salivary glands of the female tick amblyomma americanum (acari: ixodidae).ticks infest a wide range of hosts while bypassing their immune, inflammatory and haemostatic responses during their extended feeding, which may last for more than two weeks. here, we present a transcriptome analysis of 3868 expressed sequence tags (ests) from three cdna libraries generated from the salivary glands of adult female ambyomma americanum ticks at different stages of feeding. we applied a normalization step for one library, significantly decreasing the abundance of mitochondrial sequ ...200919320755
francisella-like endosymbiont dna and francisella tularensis virulence-related genes in brazilian ticks (acari: ixodidae).ticks are vectors of a variety of pathogens, including francisella tularensis. bacteria in the genus francisella have been identified mostly in the northern hemisphere and include tick endosymbionts. francisella has never been described in brazil, where amblyomma spp. ticks are known as the vector of many bacterial zoonotic pathogens. in the present work, we have identified bacterial dna sequences with identity to francisella genes in amblyomma dubitatum neumann dermacentor nitens (neumann), and ...200919351090
gastrointestinal parasites and ectoparasites of bradypus variegatus and choloepus hoffmanni sloths in captivity from costa rica.sloths may serve as host to a wide range of parasites. however, there is little information available on the types of parasites that affect costa rica's sloth population. during a 1-yr period, 65 specimens of costa rican sloth species (choloepus hoffmanni; n = 56) and bradypus variegates; n = 9) from a local zoo were sampled. fecal samples were evaluated using two different diagnostic techniques, sheather's flotation and sedimentation. concurrently, these sloths were examined for ectoparasites. ...200919368244
microbial communities and interactions in the lone star tick, amblyomma americanum.to quantify microbial composition and interactions, we identified prokaryotic communities in the lone star tick (amblyomma americanum) based on 16s rrna gene sequences and direct probing. the lone star tick is the vector of emerging diseases and host to additional symbionts of unknown activity, and is representative of other blood-sucking arthropods. we evaluated the potential for vertical (transovarial) transmission by molecular analysis of microbial symbionts from egg and larval clutches. dire ...200819378409
ticks and tick-borne pathogens and putative symbionts of black bears (ursus americanus floridanus) from georgia and florida.ticks were collected from 38 black bears (ursus americanus floridanus) from northwestern florida (n = 18) from 2003 to 2005 and southern georgia (n = 20) in 2006. five species (amblyomma americanum, a. maculatum, dermacentor variabilis, ixodes scapularis, and i. affinis) were collected from florida bears, and 4 species (a. americanum, a. maculatum, d. variabilis, i. scapularis) were collected from bears in georgia. ixodes scapularis was the most frequently collected tick, followed by d. variabil ...200919413369
new developments in canine hepatozoonosis in north america: a review.abstract : canine hepatozoonosis is caused by hepatozoon canis and hepatozoon americanum, apicomplexan parasites transmitted to dogs by ingestion of infectious stages. although the two agents are phylogenetically related, specific aspects, including characteristics of clinical disease and the natural history of the parasites themselves, differ between the two species. until recently, h. canis infections had not been clearly documented in north america, and autochthonous infection with h. america ...200919426444
ecology of amblyomma neumanni (acari: ixodidae).the life cycle of amblyomma neumanni was described studying the seasonal distribution of free-living stages and parasitic phases during two consecutive years. development periods of engorged ticks under different photoperiod conditions were recorded. larvae of a. neumanni have the peak of abundance in autumn. nymphs reach the peak in winter. females were collected on cattle from autumn to late spring. the seasonal distribution pattern of females showed a bimodal curve, with a peak in autumn and ...200919427299
a sustained release gel formulation of doramectin for control of lone star ticks (acari: ixodidae) and horn flies (diptera: muscidae) on cattle.a gel formulation formed by incorporating technical doramectin into a 10% hydroxypropyl methylcellulose aqueous solution was used to subcutaneously inject steers at varying dosages. doramectin serum concentration of steers receiving 600 microg (ai)/kg body weight declined from 21.9 ppb at 0.5 wk to below detectable at 8 wk postinjection. the 1,200 microg (ai)/kg injection resulted in serum concentrations of 29.1 ppb at 0.5 wk and declined to 0.5 ppb at 8 wk postinjection. both the 600 and 1,200 ...200919449664
efficacy of eprinomectin and doramectin against amblyomma americanum (acari: ixodidae) on cattle.steers were treated with doramectin or eprinomectin by daily oral capsule for 28 consecutive days. the level of doramectin in the serum of steers treated at 200 microg/kg/d reached a maximum of 104.0 +/- 22.1 ppb at day 21 and declined from 93.3 +/- 20.5 ppb on the final day of treatment to below detectable by day 56. steers treated at 50 microg/kg/d reached a maximum level of doramectin in the serum of 24.7 +/- 1.2 ppb on day 21 and declined from 24.7 +/- 0.6 ppb on the final day of treatment t ...200919449665
transovarial and trans-stadial transmission of rickettsiae africae in amblyomma variegatum ticks. 200919456811
amblyomma boeroi n. sp. (acari: ixodidae), a parasite of the chacoan peccary catagonus wagneri (rusconi) (artiodactyla: tayassuidae) in argentina.all parasitic stages of amblyomma boeroi n. sp. (acari: ixodidae) are described here from catagonus wagneri (rusconi) in argentina. the diagnostic characters for the male are a combination of orbited eyes, a 2/2 dental formula, coxa iv considerably larger than coxae i-iii and with a long, sickle-shaped, medially directed spur arising from its internal margin, a scutum which is light grey to very pale ivory in colour, and the absence of a postanal groove. the diagnostic characters for the females ...200919472076
hepatozoon canis infecting dogs in the state of espírito santo, southeastern brazil.from may 2007 to march 2008, blood samples were collected from 92 healthy dogs living in 21 households (17 farms in rural area, and 4 homes in urban area) in 6 counties of the state of espírito santo, southeastern brazil. in addition, ticks were collected from these dogs. a mean of 4.4+/-3.0 dogs (range: 1-12) were sampled per household; 78 and 14 dogs were from rural and urban areas, respectively. polymerase chain reaction (pcr) designed to amplify fragments of the 18s rdna gene of babesia spp ...200919482427
prospective health assessment of fort campbell, kentucky patrons bitten by ticks.amblyomma americanum is an aggressive human-biting tick that transmits several known human pathogens and is associated with a lyme disease-like illness of unknown etiology. to determine the frequency, distinguishing clinical characteristics, and etiology ofa. americanum-associated illness and identify associated risk factors, a prospective study of adult tick-bite victims was conducted at fort campbell from 2005-2007. forty-two participants submitted ticks, none of which contained borrelia lones ...200919485114
demonstration of borrelia burgdorferi sensu stricto infection in ticks from the northeast of mexico.borrelia burgdorferisensu lato infection has been confirmed in clinical cases in the northeast of mexico; however, the bacterium has not been identified as infecting the tick vector ixodes, amblyomma and dermacentor ticks were collected from mammals and plants in northeastern mexico and examined for borrelia. eighteen of 214 ticks were pcr-positive for the fla and 16s rrna genes and 15 for the ospa gene. southern blotting with a fla probe and sequencing of ospa genes confirmed infection with b. ...200919489926
immunisation with recombinant proteins subolesin and bm86 for the control of dermanyssus gallinae in poultry.dermanyssus gallinae has a worldwide distribution and is considered to be the most serious and economically significant ectoparasite affecting egg-laying poultry in europe. recombinant bm86 and subolesin proteins derived from boophilus microplus ticks and aedes albopictus mosquitoes were used to immunise poultry in an attempt to control d. gallinaein vitro. immunisation with subolesin and bm86 stimulated different profiles of igy response, whilst bm86 but not subolesin was recognized by igy on w ...200919501789
acquisition and transmission of hepatozoon canis (apicomplexa: hepatozoidae) by the tick amblyomma ovale (acari: ixodidae).the present study aimed to evaluate under controlled conditions the acquisition of hepatozoon canis by amblyomma ovale after feeding on infected dogs, and the subsequent induction of infection in uninfected dogs that ingested the experimentally infected ticks. two h. canis naturally infected dogs were infested with a. ovale adult ticks derived from an uninfected laboratory tick colony. after feeding, two a. ovale females presented h. canis oocysts in the hemolymph at the first and fourth days af ...200919501969
microarray analysis of gene expression changes in feeding female and male lone star ticks, amblyomma americanum (l).a collection of est clones from female tick amblyomma americanum salivary glands was hybridized to rna from different feeding stages of female tick salivary glands and from unfed or feeding adult male ticks. in the female ticks, the expression patterns changed dramatically upon starting feeding, then changed again towards the end of feeding. on beginning feeding, genes possibly involved in survival on the host increased in expression as did many housekeeping genes. as feeding progressed, some of ...200919514082
[stari--a new tick borne spirochetosis].southern tick associated rash illness (stari), also known as masters disease is caused by borrelia lonestari spirochetes and it is transmitted by amblyomma americanum tick. early symptoms of stari are similar to early lyme borreliosis (skin rash resembling erythema migrans). in diagnostic of stari traditional methods are not effective. the decision of antibiotic treatment (similar to lyme borreliosis) still remain based on clinical picture.200919522220
closing the gaps between genotype and phenotype in rickettsia rickettsii.rocky mountain spotted fever (rmsf) caused by rickettsia rickettsii is a severe rickettsiosis that occurs in nearly every state of the continental usa. rmsf is endemic in central and southern america, with recent well-documented cases in mexico, costa rica, panama, colombia, brazil, and argentina. rmsf is the most malignant among known rickettsioses causing severe multiorgan dysfunction and high case fatality rates, which can reach 73% in untreated cases. variations in pathogenic biotypes of r. ...200919538260
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 ...200919538276
male engorgement factor: role in stimulating engorgement to repletion in the ixodid tick, dermacentor variabilis.mating in ticks results in profound physiological changes that eventually results in egg production. in the american dog tick, dermacentor variabilis, mating causes partially blood-fed female ticks to commence rapid engorgement to repletion and eventual detachment from the host and egg laying. the peptidic male pheromone (engorgement factor alpha/beta) transferred to the female during mating is known only from a single tick species, amblyomma hebraeum, and was shown to consist of two peptides pr ...200919538967
a borreliacidal factor in amblyomma americanum saliva is associated with phospholipase a(2) activity.previous work in our laboratory described the in vitro killing of borrelia burgdorferi when co-cultured with saliva from adult amblyomma americanum. borreliacidal activity was not evident using ixodes scapularis saliva. mixing trypsin with saliva eliminated the borreliacidal activity of a. americanum saliva, while incorporating a trypsin inhibitor restored all borreliacidal activity, indicating this factor was of protein or peptide origin. one dimensional page indicated at least 7 major protein ...200919545533
the life cycle of amblyomma auricularium (acari: ixodidae) using rabbits (oryctolagus cuniculus) as experimental host.the life cycle of amblyomma auricularium (conil) is reported for the first time, using rabbits as experimental host. developmental periods of free-living stages were observed in an incubator at 27 +/- 1 degrees c, 80 +/- 10% rh and 24 h darkness. the complete life cycle, including pre-feeding periods for each parasitic stage, ranged from 97 to 162 days. the overall sex ratio was 1.16:1 (m:f). feeding and premolt periods, molting success, and engorgement weight of nymphs were statistically differ ...201019554463
salivary gland degeneration and vitellogenesis in the ixodid tick amblyomma hebraeum: surpassing a critical weight is the prerequisite and detachment from the host is the trigger.the normal engorged body weight of female ixodid ticks (acari: ixodidae) is about 100x the unfed weight. virgin female amblyomma hebraeum normally do not feed beyond 10x the unfed weight. however, about 10-20% of a population of virgins will feed to perhaps 20x the unfed weight, but not much beyond that. in a. hebraeum, when females surpass about 10x the unfed weight, the following changes in physiology occur if they are removed from the host: (a) they will not reattach if given the opportunity, ...200919555693
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 ...200919583912
babesia spp. infection in dogs from rural areas of são paulo state, brazil.the status of babesia spp. infection in dogs from rural areas of são paulo state, brazil was studied. for this, 150 animals were examined by blood smears and by pcr; the presence of tick infestation was also investigated. by the blood smear examination, 3 animals (2%) were detected positive and by pcr for babesia spp. 12 (8%) were positive, with bands visualized in 450 bp. rhipicephalus sanguineus or amblyomma spp. were found on 36 (24%) of the 150 dogs. amblyomma species found were a. cajennens ...200919602312
[occurrence of ticks (acari: ixodidae) in the municipality of goiatins, tocantins].due to a suspected human case of brazilian lyme-like disease in the city of goiatins, tocantins state, an epidemiological survey was carried out in eight counties in this region during september 2007 and february 2008, where 1,890 ticks were collected from domestic animals and from the environment. a total of eight tick species were identified: rhipicephalus sanguineus, rhipicephalus (boophilus) microplus, dermacentor nitens, amblyomma cajennense, amblyomma oblongoguttatum, amblyomma ovale, ambl ...200919602318
noncompetitive inhibitor of thrombin. 200919644995
detection and identification of rickettsial agents in ticks from domestic mammals in eastern panama.several outbreaks of rocky mountain spotted fever have occurred in recent years in colombian communities close to the border with panama. however, little is known about rickettsiae and rickettsial diseases in eastern panamanian provinces, the darien province and the kuna yala, located north of the endemic area in colombia. in 2007, 289 ticks were collected in several towns from dogs, horses, mules, cows, and pigs. dna was extracted from 124 dermacentor nitens, 64 rhipicephalus sanguineus, 43 amb ...200919645289
evidence for the presence of francisella and spotted fever group rickettsia dna in the tick amblyomma fimbriatum (acari: ixodidae), northern territory, australia.ticks (n = 252) were collected from five wild-caught reptile species during routine trapping in the djukbinj national park and fogg dam reserve, northern territory, australia. pooling of ticks (one to four ticks per pool), according to sex or host animal, resulted in 187 samples used for screening for the presence of rickettsia species via molecular methods. rickettsia dna was detected via the amplification of the glta, ompa, and ompb genes in 57 (34%) of the 187 tick samples, all of which conta ...200919645299
new approaches to detection and identification of rickettsia africae and ehrlichia ruminantium in amblyomma variegatum (acari: ixodidae) ticks from the caribbean.imported from africa in the 1700s and despite frequent modern eradication efforts, amblyomma variegatum (f.) spread through the caribbean by cattle transport, small ruminants, and migrating birds. a. variegatum is a vector for rickettsia africae, the causative agent of african tick bite fever, and ehrlichia ruminantium, the causative agent of heartwater. we examined 95 a. variegatum and six rhipicephalus (boophilus) microplus (canestrini) collected from cattle at an abattoir in antigua. engorged ...200919645301
community-based prevention of lyme disease and other tick-borne diseases through topical application of acaricide to white-tailed deer: background and rationale.this series of articles describes the first large-scale experiment designed to explore the efficacy of reducing the risk of tick-borne disease in highly endemic communities of the northeastern and mid-atlantic united states through deployment of a self-application device that treats white-tailed deer with acaricide to prevent feeding by adult ixodes scapularis ticks and all stages of amblyomma americanum ticks where both species occur. the results of the multicenter study are reported in the acc ...200919650729
effectiveness of the 4-poster passive topical treatment device in the control of ixodes scapularis and amblyomma americanum (acari: ixodidae) in new jersey.twenty-five "4-poster" feeders were placed throughout a 5.2 km(2) study area within a secured military facility situated in a hyperendemic area for lyme disease in central monmouth county, new jersey. calculated levels of control, relative to untreated areas, peaked at 82.7%, 77.3%, and 94.2% for of host-seeking ixodes scapularis say larvae, nymphs, and adults, respectively, within 5 years of deployment. control of host-seeking amblyomma americanum (l.) peaked at 99.2%, 89.5%, and 96.9% for larv ...200919650733
the impact of 4-poster deer self-treatment devices at three locations in maryland.from 1998-2002 twenty-five deer self-treatment devices (4-posters), using 2% amitraz, were operated at three locations in maryland to determine their effectiveness in controlling blacklegged ticks, ixodes scapularis say, and lone star ticks, amblyomma americanum (l.). each treatment site was approximately 518 ha and paired with a similar site lacking 4-posters. locations varied in deer density, tick abundance, and land use. flagging for host-seeking ticks showed declines in tick populations at a ...200919650735
sustained control of gibson island, maryland, populations of ixodes scapularis and amblyomma americanum (acari: ixodidae) by community-administered 4-poster deer self-treatment bait stations.in 1998, twenty-five 4-poster deer treatment bait stations were deployed on gibson island (gi), maryland, as part of the u.s. department of agriculture (usda) northeast area-wide tick control project. treatments concluded in june 2002, having achieved 80% and 99.5% control of blacklegged ticks, ixodes scapularis, and lone star ticks, amblyomma americanum, respectively. no area-wide tick control was attempted again on the island until 2003, when 15 dandux-manufactured 4-posters were purchased by ...200919650736
the united states department of agriculture's northeast area-wide tick control project: summary and conclusions.from 1997 to 2002, the u.s. department of agriculture's northeast area-wide tick control project used acaricide-treated 4-poster deer treatment bait stations in five eastern states to control ticks feeding on white-tailed deer. the objectives of this host-targeted technology were to reduce free-living blacklegged (ixodes scapularis say) and lone star (amblyomma americanum [l.]) tick populations and thereby to reduce the risk of tick-borne disease. during 2002 to 2004, treatments were suspended, ...200919650739
cloning and characterization of rhipicephalus appendiculatus voraxinalpha and its effect as anti-tick vaccine.male tick-derived voraxinalpha and voraxinbeta, a pair of testicular proteins, are transferred to female via copulation to stimulate female blood feeding in the tick amblyomma hebraeum (a. hebraeum). immunized animals with recombinant (r-)voraxinalpha and voraxinbeta have been shown as highly resistant to the tick infestation. in this study, we describe the cloning and characterization of voraxinalpha homologue from the tick rhipicephalus appendiculatus (r. appendiculatus), the major vector for ...200919665610
current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and ehrlichia ewingii ehrlichiosis.anaplasma phagocytophilum, ehrlichia chaffeensis and ehrlichia ewingii are emerging tick-borne pathogens and are the causative agents of human granulocytic anaplasmosis, human monocytic ehrlichiosis and e. ewingii ehrlichiosis, respectively. collectively, these are referred to as human ehrlichioses. these obligate intracellular bacterial pathogens of the family anaplasmataceae are transmitted by ixodes spp. or amblyomma americanum ticks and infect peripherally circulating leukocytes to cause inf ...200919681699
[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.200919684990
ehrlichia chaffeensis infections in drosophila melanogaster.ehrlichia chaffeensis is an obligate, intracellular bacterium, transmitted by the tick amblyomma americanum, and is the causative agent of human monocytic ehrlichiosis infections. we previously demonstrated that e. chaffeensis is capable of growing in drosophila s2 cells. therefore, we tested the hypothesis that e. chaffeensis can infect adult drosophila melanogaster. adult drosophila organisms were experimentally challenged with intra-abdominal injections of bacteria. ehrlichia-infected flies s ...200919687202
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