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[ectoparasites of small wild mammals from the adjacent areas of itapecuru river and environmental preservation area of inhamum, state of maranhão, brazil].during fauna studies, thirty-six wild mammals were collected in adjacent areas of itapecuru river and environmental preservation area of inhamum, state of maranhão, brazil. they were sampled for ectoparasites. the following specimens of the order rodentia and its respective ectoparasites were identified: akodon sp. (androlaelaps sp. and laelaps sp.), oecomys sp. (androlaelaps sp. and amblyomma cajennense), oligoryzomys sp. (androlaelaps sp. laelaps sp. and amblyomma sp.) e oryzomys megacephalus ...200820059819
[seasonal dynamics of the free-living stages of amblyomma cajennense and amblyomma dubitatum (acari: ixodidae) in an endemic area for spotted fever in coronel pacheco region, minas gerais state].a study on the population behavior of amblyomma cajennense and amblyomma dubitatum larvae, nymphs and adult free-living stages was carried out in coronel pacheco county, minas gerais state, brazil, a spotted feverendemic area from may 2006 to april 2008. larvae of amblyomma sp. were collected from pasture using the technique of drag sampling with flannelette during may to october 2006, starting from february 2007 to november 2007 and starting from march 2008. well-defined peaks of populations oc ...200820059821
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
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
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
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
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
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
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
neuropeptide discovery in ixodoidea: an in silico investigation using publicly accessible expressed sequence tags.the ixodoidea (ticks) are important vectors in the transmission of many human diseases; for example, the blacklegged tick ixodes scapularis is the major vector in the transmission of lyme disease, the most frequently reported vector-borne illness in the united states. the development of expressed sequence tags (ests) for ixodoidean cdna libraries, and their public deposition, has generated a rich resource for protein discovery in members of this taxon, thereby providing an opportunity for better ...200818495123
failure by engorged stages of the lone star tick, amblyomma americanum, to react to assembly pheromone, guanine and uric acid.response to tick-exposed filter paper discs (tick excreta) by fed and non-fed stages of the lone star tick amblyomma americanum (l.) (acari: ixodidae) was examined from larva to adult. by contrast with engorged stages, each non-fed stage exhibited a classic arrestment response to assembly pheromone, characterized by lack of movement, retraction of legs and formation of small groups; this response was seen in approximately 75% of ticks that made contact with pheromone-treated surfaces. less prono ...200818498612
twelve-hour duration testing of cream formulations of three repellents against amblyomma americanum.the repellent efficacies of the u.s. military repellent 33% n,n-diethyl-3-methylbenzamide (deet), 10% and 20% (1s, 2's) 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (ss220) and 10% and 20% 1-methyl-propyl-2-(hydroxyethyl)-1-piperidinecarboxylate (bayrepel) cream formulations on human volunteers against the lone star tick amblyomma americanum (l.) were evaluated in a simulated forest floor environment over a 12-h testing period. at 2-h intervals, volunteers, with repellent applied in a 5-cm-wi ...200818498614
immunomodulatory arsenal of nymphal ticks.ticks have developed their own immunomodulatory mechanisms to inhibit the host inflammatory response. one of them involves the ability to subvert the cytokine network at the site of tick feeding by secreting cytokine binding molecules. most studies have focused on the immunomodulatory prowess of adult female ticks. here we describe anti-cytokine activity in salivary gland extracts (sges) prepared from 2-day-fed nymphs of dermacentor reticulatus fabricius, ixodes ricinus l., rhipicephalus appendi ...200818498617
a quantitative real-time pcr assay for ehrlichia ruminantium using pcs20.heartwater is a tick borne disease that affects ruminants and wild animals in africa south of the sahara. it is caused by ehrlichia ruminantium and transmitted by the tick amblyomma hebraeum. the protocols currently used to detect heartwater take several days to complete. here, we describe the development of a pcs20 quantitative real-time pcr taqman probe assay to detect e. ruminantium in livestock blood and ticks from the field. the assay is based on the conserved pcs20 gene region of e. rumina ...200818511221
spatial distribution and impact of cattle-raising on ticks in the pantanal region of brazil by using the co(2) tick trap.this study evaluates the impact of cattle-raising on ticks associated with wildlife in the pantanal region of brazil, by trapping free-living ticks using a co(2) tick trap. the traps were equally distributed in two areas: a 600-ha protected area (pa) and the nhumirim ranch (nr). both areas are contiguous and located at the sub-region of nhecolândia (18 degrees 59's; 56 degrees 39'w), pantanal, brazil. in each area, four habitat types were selected: cerrado (tropical savanna), forest patches, lak ...200818454288
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
intracellular infection of tick cell lines by the entomopathogenic fungus metarhizium anisopliae.several fungal pathogens are able to enter and persist within eukaryotic cells as part of their infectious life cycle. metarhizium anisopliae is a saprophytic entomopathogenic fungus virulent towards numerous tick species, including those within the genera ixodes and amblyomma. infection of the target organism by this fungus proceeds via several steps, including adhesion and penetration of the host cuticle, proliferation within tissues and the haemolymph, and eventual eruption through the host c ...200818524924
identification of two genes essential for sperm development in the male tick amblyomma hebraeum koch (acari: ixodidae).in most ticks of the family ixodidae, gonad maturation and spermatogenesis are stimulated by the taking of a blood meal. previous work from this laboratory identified 35 genes that are up-regulated by feeding [weiss, b.l., stepczynski, j.m., wong, p., kaufman, w.r., 2002. identification and characterization of genes differentially expressed in the testis/vas deferens of the fed male tick, amblyomma hebraeum. insect biochemistry and molecular biology 32, 785-793]. the functions of most of these g ...200818549958
[amblyomma tigrinum in the municipality of lages, sc, and biology observations under laboratory conditions].to study the biological features of amblyomma tigrinum, samples of engorged females collected from dogs in the city of lages, sc, brazil, were maintained in petri dishes into an incubator at 27+/-1 degrees c and 80+/-10% rh, for egg laying. for the development of the subsequent experimental phases, artificial infestations were performed in rabbits using the technique of the cotton bag glued to the ear's base. the mean period of hatch, feeding and larval molt were 11.67, 5.93 and 10.96 days, resp ...200818554444
ticks, amblyomma rotundatum (acari: ixodidae), on toads, chaunus schneideri and chaunus granulosus (anura: bufonidae), in northern argentina.this communication provides notes on 2 species of toads, chaunus schneideri and chaunus granulosus, infested with ixodid ticks, amblyomma rotundatum, from the provinces of corrientes and formosa in northern argentina. chaunus schneideri is a new amphibian host record for a. rotundatum, a species previously reported to parasitize other anurans and also reptiles. we examined 74 ticks on 5 toads. all ticks were a. rotundatum; all adults were females, and all developmental stages were randomly attac ...200818564766
amblyomma triste koch, 1844 (acari: ixodidae): hosts and seasonality of the vector of rickettsia parkeri in uruguay.amblyomma triste koch, 1844, the tick species most frequently involved in human bites in uruguay, has been implicated as a vector of human rickettsiosis. seasonal abundance of adult a. triste was examined by standard flagging at three sites where human tick bites and cases of the disease have been reported. adult tick activity occurred from august to february (end of winter to mid summer in the southern hemisphere) with a peak in spring. activity declined in step with decreasing temperatures and ...200818565680
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
rocky mountain spotted fever in argentina.we describe the first molecular confirmation of rickettsia rickettsii, the cause of rocky mountain spotted fever (rmsf), from a tick vector, amblyomma cajennense, and from a cluster of fatal spotted fever cases in argentina. questing a. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in jujuy province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. dna of r. rickettsii was amplified from a pool ...200818385370
a novel sine family occurs frequently in both genomic dna and transcribed sequences in ixodid ticks of the arthropod sub-phylum chelicerata.reassociation kinetics and flow cytometry data indicate that ixodid tick genomes are large, relative to most arthropods, containing>or=10(9) base pairs. the molecular basis for this is unknown. we have identified a novel small interspersed element with features of a trna-derived sine, designated ruka, in genomic sequences of rhipicephalus appendiculatus and boophilus (rhipicephalus) microplus ticks. the sine was also identified in expressed sequence tag (est) databases derived from several tissu ...200818394826
characterization of rickettsial infection in amblyomma americanum (acari: ixodidae) by quantitative real-time polymerase chain reaction.several species of the spotted fever group rickettsia (sfgr), with considerable variation in vertebrate host pathogenicity, are present in ticks in the united states. in this study, quantitative real-time pcr (qpcr) was used to characterize the growth and the distribution of rickettsia amblyommii in selected tissues (salivary glands, gut, and ovaries) of naturally infected amblyomma americanum (l.) (acari: ixodidae), during bloodmeal acquisition and throughout vertical transmission to eggs and p ...200818402143
amblyomma variegatum in cattle in marie galante, french antilles: prevalence, control measures, and infection by ehrlichia ruminantium.we report marie galante as one of the caribbean islands most heavily infested by the tropical bont tick (tbt) amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. in 2005, a survey was undertaken to assess the prevalence of tbt infestation in cattle, the prevalence of ehrlichia ruminantium infection in tbts, and the tick control measures implemented by livestock owners. a random sample of 195 cattle herds out of 1885 recorded on the islan ...200818406061
molecular identification of rickettsia felis in ticks and fleas from an endemic area for brazilian spotted fever.rickettsioses are arthropod-borne diseases caused by parasites from the order rickettsiales. the most prevalent rickettsial disease in brazil is brazilian spotted fever (bsf). this work intends the molecular detection of those agents in ectoparasites from an endemic area of bsf in the state of espírito santo. a total of 502 ectoparasites, among them amblyomma cajennense, amblyomma dubitatum (a. cooperi), riphicephalus sanguineus, anocentor nitens and ctenocephalides felis, was collected from dom ...200818425272
human perception and awareness of ticks in a south australian rural community and implications for management of amblyomma triguttatum triguttatum.the ornate kangaroo tick, amblyomma triguttatum triguttatum, is invasive on yorke peninsula, south australia. to assess the potential for developing comprehensive management strategies for the species, we mailed 1,000 surveys to yorke peninsula residents to investigate community perceptions of ticks, gather information on tick-host ecology, and assess whether or not occupation and length of residence affected whether residents had seen ticks. the response rate was 32%; most respondents (63%) had ...200818427936
the tick fauna of sulawesi, indonesia (acari: ixodoidea: argasidae and ixodidae).twenty-six species of ticks are reported from the island of sulawesi (celebes), indonesia. these include two species of soft ticks (argasidae), carios batuensis and c. vespertilionis, and the following 24 species of hard ticks (ixodidae): amblyomma babirussae, a. breviscutatum, a. cordiferum, a. fimbriatum, a. helvolum, a. testudinarium, a. trimaculatum, a. varanense, dermacentor atrosignatus, d. steini, haemaphysalis celebensis, h. hystricis, h. kadarsani, h. papuana, h. psalistos, h. renschi, ...200818427937
experimental and field studies on the suitability of raccoons (procyon lotor) as hosts for tick-borne pathogens.we investigated the experimental susceptibility and natural exposure of raccoons (procyon lotor) to five tick-borne pathogens of human and veterinary importance, ehrlichia canis, e. chaffeensis, e. ewingii, anaplasma phagocytophilum (apvariant 1 and ap-ha hge-1 strains), and borrelia lonestari. infections were assessed by polymerase chain reaction (pcr), indirect fluorescent antibody (ifa) testing, and/or culture isolation methods for at least 30 days postinoculation (dpi). two e. chaffeensis-in ...200818429696
geographic distribution and genetic diversity of the ehrlichia sp. from panola mountain in amblyomma americanum.a novel ehrlichia, closely related to ehrlichia ruminantium, was recently discovered from panola mountain state park, ga, usa. we conducted a study to determine if this agent was recently introduced into the united states.200818433500
natural and experimental infection of white-tailed deer (odocoileus virginianus) from the united states with an ehrlichia sp. closely related to ehrlichia ruminantium.an ehrlichia sp. (panola mountain [pm] ehrlichia sp.) closely related to ehrlichia ruminantium was recently detected in a domestic goat experimentally infested with lone star ticks (lsts, amblyomma americanum) collected from georgia, usa. the infected goat exhibited pyrexia and mild clinical pathologic abnormalities consistent with ehrlichiosis. at least two other ehrlichia species (ehrlichia chaffeensis and ehrlichia ewingii) are maintained in nature by a cycle involving lsts as the primary vec ...200818436670
molecular detection of spotted fever group rickettsiae in ticks from ethiopia and chad.dna extracted from 363 ticks collected in ethiopia and 9 ticks collected in chad, africa were screened by pcr to detect dna from spotted fever group rickettsiae. fifteen ticks (4.1%) collected in ethiopia and one tick (11%) collected in chad tested positive when pcr targeting the glta and ompa rickettsial genes was performed. pcr-positive products of the glta and ompa genes were used for dna sequencing. rickettsia africae was detected in 12/118 amblyomma lepidum and in 1/2 a. variegatum. also, 2 ...200818440576
tick-borne diseases in north carolina: is "rickettsia amblyommii" a possible cause of rickettsiosis reported as rocky mountain spotted fever?cases of rocky mountain spotted fever (rmsf) in north carolina have escalated markedly since 2000. in 2005, we identified a county in the piedmont region with high case numbers of rmsf. we collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (sfgr) might be emerging. amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. in contrast, dermacen ...200818447622
stari, or masters disease: lone star tick-vectored lyme-like illness.lyme-like illness (also known as southern tick-associated rash illness [stari] or masters disease) is vectored by the lone star tick (amblyomma americanum). lyme-like illness lesions, which are similar to the erythema migrans rash of lyme disease, tend to have lymphocytic dermal infiltrates. with the exception of borrelia lonestari, the possible causative agent or agents of lyme-like illness have not been cultured. more research is needed to fully understand this newly recognized zoonosis. clini ...200818452807
rickettsia amblyommii infecting amblyomma americanum larvae.polymerase chain reaction analysis of amblyomma americanum adults, nymphs, and larvae from aberdeen proving ground, md (apg), revealed a very high prevalence of a spotted fever group (sfg) rickettsia. restriction fragment length polymorphism (rflp) and sequence analysis identified "rickettsia amblyommii." this organism is not yet described or well studied, and its pathogenicity is unknown; however, investigations of the organism are warranted because of its high prevalence in a. americanum. this ...200818171102
molecular and parasitological survey of hepatozoon canis (apicomplexa: hepatozoidae) in dogs from rural area of sao paulo state, brazil.hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, rhipicephalus sanguineus. two distinct species of hepatozoon genus can infect dogs, h. canis and h. americanum. routine tests to detect the disease are based on direct examination of gametocytes on giemsa-stained blood smears. the objectives of this study were the investigation of infection prevalence in rural area dogs, the comparison of diagnostics by blood smear examination and polymer ...200818188597
biological aspects of amblyomma brasiliense (acari: ixodidae) under laboratory conditions.although amblyomma brasiliense aragão 1908 has been reported as one of the most aggressive ticks to humans in brazil, information about the biology of this tick species is virtually inexistent. this work reports data on the life cycle of a. brasiliense fed on rabbits and pigs and maintained in an incubator at 20 degrees c, 90% rh and 12 h of light for off-host development. tick yield of adult females fed on pigs and rabbits was 81.2% and 58.3%, respectively. females fed on pigs had mean engorgem ...200818188669
bothriocroton oudemansi (neumann, 1910) n. comb. (acari: ixodida: ixodidae), an ectoparasite of the western long-beaked echidna in papua new guinea: redescription of the male and first description of the female and nymph.specimens of amblyomma oudemansi (neumann, 1910) were collected in papua new guinea from an endangered monotreme, zaglossus bruijni (peters & doria), the western long-beaked echidna. these ticks were compared morphologically and molecularly with species formerly assigned to aponomma neumann, 1899 (now included in bothriocroton keirans, king, & sharrad, 1994 or amblyomma koch, 1844), and a phylogeny was generated. based on our results, we reassign this tick to bothriocroton, as b. oudemansi (neum ...200818210218
climate changes and suitability for the ticks amblyomma hebraeum and amblyomma variegatum (ixodidae) in zimbabwe (1974-1999).the spread of amblyomma hebraeum has been reported in zimbabwe. at the same time there was little or no spread in the distribution of amblyomma variegatum. this paper examines the climatic cycles and their trends in the period 1974-1999 with a view to explaining the abiotic causes of this spread, and of forecasting the likely tendency in climate suitability for both tick species. an annual data-set of rainfall and air temperature was used as a source for climate, together with a habitat-modeling ...200818083309
new morphological data on fat bodies of semi-engorged females of amblyomma cajennense (acari: ixodidae).the present ultramorphological, histological and ultrastructural study on the fat body of semi-engorged females of amblyomma cajennense revealed that this tissue is diffuse and consists of strands of cells surrounding the tracheal trunks. morphometric analysis showed that the cellular and nuclear areas of round-shaped trophocytes are larger than those of cuboidal trophocytes, indicating that the arrangement of the former provides more contact area with the haemolymph. in this species, the fat bo ...200818215525
expressed sequence tags (ests) from the salivary glands of the tick amblyomma cajennense (acari: ixodidae).the neotropical tick amblyomma cajennense is a significant pest to domestic animals, the most frequently human-biting tick in south america and the main vector of brazilian spotted fever (caused by rickettsia rickettsii), a deadly human disease. the purpose of this study is to characterize the adult a. cajennense salivary gland transcriptome by expressed sequence tags (ests). we report the analysis of 1754 clones obtained from a cdna library, which reveal mainly transcripts related to proteins i ...200818243270
serosurvey of rickettsia spp. in dogs and humans from an endemic area for brazilian spotted fever in the state of são paulo, brazil.the present study provides a rickettsial serosurvey in 25 dogs and 35 humans in an endemic area for brazilian spotted fever in the state of são paulo, where the tick amblyomma aureolatum is the main vector. testing canine and human sera by indirect immunofluorescence against four rickettsia antigens (r. rickettsii, r. parkeri, r. felis and r. bellii) showed that 16 (64%) of canine sera and 1 (2.8%) of human sera reacted to at least one of these rickettsial antigens with titers >0r= 64. seven can ...200818278271
detection of two bartonella tamiae-like sequences in amblyomma americanum (acari: ixodidae) using 16s-23s intergenic spacer region-specific primers.four hundred and sixty-six questing amblyomma americanum (l.) (acari: ixodidae) from carolina county, va, and 98 questing a. americanum from chatham county, nc, were screened by polymerase chain reaction (pcr) for the bartonella 16s-23s intergenic spacer region. two amplicons, approximately 270-280 bp, were detected in two ticks from virginia. based upon pcr and sequencing, an adult male and adult female tick harbored dna sequences closely related to bartonella tamiae (dq395180). bartonella dna ...200818283962
two usa ehrlichia spp. cause febrile illness in goats.ehrlichia spp. are not currently recognized as a cause of illness in goats in the usa, but three ehrlichia are enzootic in lone star ticks (amblyomma americanum) in the eastern usa, and related bacteria in other countries cause illness in goats. we exposed naïve goats to ehrlichia-infected amblyomma and demonstrated that infection and clinical illness can be caused by two usa species, e. ewingii and the recently discovered panola mountain ehrlichia sp. clinical features in all five goats are des ...200818328644
more about the role of 2,6-dichlorophenol in tick courtship: identification and olfactometer bioassay in amblyomma cajennense and rhipicephalus sanguineus.this study aimed to identify 2,6-dichlorophenol (2,6-dcp) in amblyomma cajennense and to evaluate its role in a. cajennense and rhipicephalus sanguineus courtship. hexanic extract from attractive females was purified by solid phase extraction and the phenol was identified by the single ion monitoring method using gc/ms. in an olfactometer, the responses of a. cajennense and r. sanguineus males to females, control rubber septa or rubber septa impregnated with 2,6-dcp at 50, 500, and 5000 ng, resp ...200818368237
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
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
[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
genetic diversity of ehrlichia ruminantium in amblyomma variegatum ticks and small ruminants in the gambia determined by restriction fragment profile analysis.understanding genetic diversity of ehrlichia ruminantium in host and vector populations is an important prerequisite to controlling heartwater by vaccination in traditional livestock systems in sub-saharan africa. we carried out a study in two phases: (i) evaluating the usefulness of the pcr-rflp assay based on the map1 coding sequence of e. ruminantium as a discriminatory tool to characterise genetic diversity, (ii) applying the technique to field samples from amblyomma variegatum ticks and sma ...200817646061
redescription of amblyomma varium koch, 1844 (acari: ixodidae) based on light and scanning electron microscopy.amblyomma varium koch, 1844 is a neotropical tick, known as the 'sloth's giant tick', with records from southern central america to argentina. it is found almost exclusively on mammals of the families bradypodidae and magalonychidae (xenarthra). differences exist in discussions with regard to the dentition of the female hypostome being either 3/3 or 4/4. the male was also originally described as having a short spur on coxa iv, but some specimens recently collected from different brazilian locali ...200818038200
african tick bite fever--papulovesicular exanthem with fever after staying in south africa.in the wake of expanding international tourism, rickettsioses are increasingly observed also in central europe. african tick bite fever is a recently described, acute febrile illness with characteristic skin lesions. it is caused by rickettsia africae, which is transmitted to humans by ticks of the amblyomma genus. a 60-year-old woman presented with a papulovesic-ular exanthem, fever, and headache after returning from south africa. a purple nodule with central necrosis ("tache noire"or "inoculat ...200818021248
detection of alpha and gamma-proteobacteria in amblyomma triste (acari: ixodidae) from uruguay.amblyomma triste is the most prevalent tick species reported in human tick bites in uruguay and has been found to be infected with rickettsia parkeri, but no other microorganisms have been reported from this tick. a sample of 254 adults of a. triste was collected by flagging on vegetation in suburban areas in southern uruguay. pools of five ticks were assembled and a screening for the dna from the resulting 51 pools was realized by pcr assays using primers for amplifying a fragment of 16s rrna g ...200818071910
[ticks (acari: ixodidae) collected in the natural reserve of the vale do rio doce, linhares, state of espírito santo].we confirm, after decades without new registers, the occurrence of the ticks amblyomma obolongoguttatum koch, 1844, a. brasiliense aragão, 1908, and a. humerale koch, 1844 in the state of espírito santo, brazil, besides the first record of a. naponense (packard, 1869) in this state.200718078608
molecular cloning of the ecdysone receptor and the retinoid x receptor from the scorpion liocheles australasiae.cdnas of the ecdysone receptor and the retinoid x receptor were cloned from the japanese scorpion liocheles australasiae, and the amino acid sequences were deduced. the full-length cdna sequences of the l. australasiae ecdysone receptor and the l. australasiae retinoid x receptor were 2881 and 1977 bp in length, respectively, and the open reading frames encoded proteins of 560 and 414 amino acids. the amino acid sequence of the l. australasiae ecdysone receptor was similar to that of the ecdyson ...200718028192
serotonin-like immunoreactivity in the central nervous system of two ixodid tick species.immunocytochemistry was used to describe the distribution of serotonin-like immunoreactive (5ht-ir) neurons and neuronal processes in the central nervous system (cns), the synganglion, of two ixodid tick species; the winter tick, dermacentor albipictus and the lone star tick, amblyomma americanum. 5ht-ir neurons were identified in the synganglion of both tick species. d. albipictus had a significantly higher number of 5ht-ir neurons than a. americanum. the labeling pattern and number of 5ht-ir n ...200718040871
cattle ticks of the genera rhipicephalus and amblyomma of economic importance in tanzania: distribution assessed with gis based on an extensive field survey.in order to implement a robust integrated tick and tick-borne disease control programme in tanzania, based on ecological and epidemiological knowledge of ticks and their associated diseases, a national tick and sero-surveillance study was carried out in all 21 regions of the mainland, as well as on mafia island, between 1998 and 2001. the current distributions of rhipicephalus appendiculatus, r. pravus, amblyomma variegatum, a. gemma, and a. lepidum are illustrated and discussed. tick distributi ...200718044004
detection of rickettsia amblyommii in association with a tick bite rash.in the summer of 2006, an amblyomma americanum tick was removed from a woman in central north carolina, who subsequently developed a rash at the site of tick attachment. when examined by polymerase chain reaction (pcr) for borrelia, anaplasma, ehrlichia, babesia, rickettsia, and bartonella dna, only the rickettsia primers generated an amplicon, which was identified as "r. amblyommii" by sequencing. to our knowledge, this is the first case in which r. amblyommii was temporally associated with a r ...200718052716
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
infection by rickettsia bellii and candidatus "rickettsia amblyommii" in amblyomma neumanni ticks from argentina.the tick species, amblyomma neumanni (acari: ixodidae) is the most frequent tick parasitizing humans in northwestern argentina. the present study evaluated the rickettsial infection among 55 a. neumanni adult free-living ticks collected in dean funes, córdoba province. ticks were individually processed by the hemolymph test with gimenez staining, isolation of rickettsia in vero cell culture by the shell vial technique, and polymerase chain reaction (pcr) targeting the citrate synthase rickettsia ...200717264991
tick paralysis of a snake caused by amblyomma rotundatum (acari: ixodidae).a lethargic southern black racer, coluber constrictor priapus dunn and wood, wild-caught in the florida keys, monroe county, fl, was found to be paralyzed by the bite of a female ixodid tick, amblyomma rotundatum koch (acari: ixodidae). removal of the tick restored the snake to normalcy within 18 h. other, earlier reported cases of tick toxicosis in reptiles are reviewed and clarified. evidently, the present incident is the only reported case of tick paralysis in a poikilotherm found in a natura ...200717294934
differential transcription of the major antigenic protein 1 multigene family of ehrlichia ruminantium in amblyomma variegatum ticks.the rickettsial pathogen ehrlichia ruminantium causes heartwater in ruminants and is transmitted by ticks of the genus amblyomma. the map1 gene, encoding the major surface protein map1, is a member of a multigene family containing 16 paralogs. in order to investigate differential transcription of genes of the map1 multigene family in vivo in unfed and feeding ticks, rna was extracted from midguts and salivary glands of e. ruminantium-infected adult female amblyomma variegatum ticks and analysed ...200717321077
parasitology and urban livestock farming in nigeria: prevalence of ova in faecal and soil samples and animal ectoparasites in makurdi.domestic environmental pollution resulting from urban livestock farming was investigated in makurdi using parasitological techniques. the test tube flotation technique was used for the parasitological analysis of animal faecal matter and soil samples collected from residential premises. ectoparasitic fauna of dogs, goats, sheep and cattle cohabiting with humans within the same residential compound were also collected and identified. the hand-picking and body brushing methods were employed to sea ...200717665765
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
variegin, a novel fast and tight binding thrombin inhibitor from the tropical bont tick.tick saliva contains potent antihemostatic molecules that help ticks obtain their enormous blood meal during prolonged feeding. we isolated thrombin inhibitors present in the salivary gland extract from partially fed female amblyomma variegatum, the tropical bont tick, and characterized the most potent, variegin, one of the smallest (32 residues) thrombin inhibitors found in nature. full-length variegin and two truncated variants were chemically synthesized. despite its small size and flexible s ...200717684009
detection of rickettsia africae in rhipicephalus (boophilus) decoloratus ticks from the republic of botswana, south africa.a total of 53 engorged adult ticks belonging to the species rhipicephalus (boophilus) decoloratus (n = 9), rhipicephalus evertsi evertsi (n = 27), rhipicephalus appendiculatus (n = 9), amblyomma hebraeum (n = 5), and hyalomma marginatum turanicum (n = 3), were removed from oryx in botswana (south africa). they were tested for the presence of spotted fever group (sfg) rickettsia and anaplasma phagocytophilum using polymerase chain reaction (pcr). seventy-seven percent of r. decoloratus as well as ...200717690416
repellent efficacy of formic acid and the abdominal secretion of carpenter ants (hymenoptera: formicidae) against amblyomma ticks (acari: ixodidae).formic acid is a substance produced by some ants for defense, trail marking, and recruitment. some animals are known to rub ants or other arthropods on parts of their plumage or fur to anoint themselves with released substances. a recent study with a semifree-ranging group of capuchin monkeys, cebus apella l., in the tietê ecological park, sao paulo, brazil, an area of occurrence of the tick species amblyomma cajennense (f.), revealed that "anting" with carpenter ants, camponotus rufipes f. (hym ...200717695031
transmission of ehrlichia chaffeensis from lone star ticks (amblyomma americanum) to white-tailed deer (odocoileus virginianus).amblyomma americanum is an aggressive ixodid tick that has been implicated as a vector for several bacterial agents. among these is ehrlichia chaffeensis, which causes human monocytic (or monocytotropic) ehrlichiosis. in this study, experimental tick transmission of e. chaffeensis from infected lone star ticks to deer was revisited, and the question of whether it would be possible to re-isolate the organism from deer was asked, because this had not been done previously. here, we were able to tra ...200717699076
[parasitism by amblyomma triste in domestic cat].amblyomma triste is an ixodidae, ectoparasite of several mammals' species, with occurrence reported in argentina, brazil, colombia, ecuador, peru, uruguay and venezuela. the aim of this work was to register the parasitism by a. triste in domestic cat (felis catus) in rio grande do sul state, brazil.200717706014
goats as alternative hosts of cattle ticks.the objective of this study was to compare the presence on goats and cattle of adult ticks that usually infest cattle. to this end ticks collected from sets of five goats were compared with those collected from sets of five cattle at 72 communal dip-tanks in the eastern region of the eastern cape province. amblyomma hebraeum was present on goats at 25 and on cattle at 39 dip-tanks, and a total of 61 goats and 138 cattle were infested. adult rhipicephalus (boophilus) microplus was present on goat ...200717708147
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
molecular and expression analysis of a family of the amblyomma americanum tick lospins.serine proteinase inhibitors (serpins) are a family of structurally similar but functionally diverse proteins that regulate several important proteolytic cascades in most branches of life. we have characterized 17 amblyomma americanum serpin cdnas here named as ;lospins' (l; an acronym for lone star tick serpin) that possess three beta-sheets, eight alpha-helices and a reactive center loop consistent with the consensus serpin superfamily secondary structures. visual inspection of deduced amino a ...200717766296
detection of a novel spotted fever group rickettsia in amblyomma parvum ticks (acari: ixodidae) from argentina.the present study evaluated the rickettsial infection in amblyomma parvum ticks collected in northwestern córdoba province, argentina. each tick was subjected to dna extraction and tested by polymerase chain reaction (pcr) targeting fragments of the rickettsial genes glta and ompb. nine (69.2%) out of 13 adult ticks yielded expected pcr products for the two rickettsial genes. products from the ompb pcr were sequenced, generating dna sequences 100% identical for the nine pcr-positive ticks. three ...200717768597
geographical distribution of ticks in turkey.turkey's tick fauna is composed of about 32 species in two families and ten genera in mammals, reptiles, and birds. the ticks of veterinary significance in the family ixodidae comprise seven genera with 28 different species. ixodes spp. are mostly seen in northern turkey. it is likely that the high rainfall and the intensive forest in this area may contribute to this observation. to date, the following species have been found to be sporadically present: amblyomma variegatum in hatay province (bo ...200717823820
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
ecological havoc, the rise of white-tailed deer, and the emergence of amblyomma americanum-associated zoonoses in the united states.two infectious diseases, and one presumably infectious disease, each vectored by or associated with the bite of the lone star tick (amblyomma americanum), were identified and characterized by clinicians and scientists in the united states during the 1980s and 1990s. these three conditions-human monocytic (or monocytotropic) ehrlichiosis (hme), ehrlichia ewingii ehrlichiosis, and southern tick-associated rash illness (stari)-undoubtedly existed in the united states prior to this time. however, th ...200717848069
ticks collected on birds in the state of são paulo, brazil.the present study reports a collection of amblyomma spp. ticks in birds from several areas of the state of são paulo, brazil. a total of 568 tick specimens (404 larvae, 164 nymphs) were collected from 261 bird specimens. from these ticks, 204 (36%) specimens (94 larvae, 110 nymphs) were reared to the adult stage, being identified as amblyomma longirostre (94 larvae, 90 nymphs), amblyomma calcaratum (13 nymphs), amblyomma nodosum (2 nymphs), and amblyomma cajennense (5 nymphs). additionally, 39 l ...200717882514
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
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