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ehrlichia chaffeensis (rickettsiales: ehrlichieae) infection in amblyomma americanum (acari: ixodidae) at aberdeen proving ground, maryland.human monocytic ehrlichiosis (hme) is a sometimes fatal, emerging tick-borne disease caused by the bacterium ehrlichia chaffeensis. it is frequently misdiagnosed because its symptoms mimic those of the flu. current evidence indicates that amblyomma americanum (l.), the lone star tick, is the major vector of hme. to determine if e. chaffeensis is present in ticks at aberdeen proving ground, md, questing a. americanum ticks were collected from 33 sites. nucleic acid was extracted from 34 adult and ...200015535577
borrelia species in host-seeking ticks and small mammals in northern florida.the aim of this study was to improve understanding of several factors related to the ecology and environmental risk of borrelia infection in northern florida. small mammals and host-seeking adult ticks were collected at several sites, and specimens were tested for the presence of borrelia species, primarily by pcr amplification. tissues from some vertebrates and ticks were initially cultured in bsk-h medium to isolate spirochetes, but none were recovered. however, comparison of partial flagellin ...200415528699
characterization of spotted fever group rickettsiae in flea and tick specimens from northern peru.evidence of spotted fever group (sfg) rickettsiae was obtained from flea pools and individual ticks collected at three sites in northwestern peru within the focus of an outbreak of febrile disease in humans attributed, in part, to sfg rickettsia infections. molecular identification of the etiologic agents from these samples was determined after partial sequencing of the 17-kda common antigen gene (htra) as well as pairwise nucleotide sequence homology with one or more of the following genes: glt ...200415528680
a thrombin inhibitor from the ixodid tick, amblyomma hebraeum.a novel thrombin inhibitor named amblin was identified from the haemolymph of the ixodid (hard) tick, amblyomma hebraeum, and the coding cdna was isolated from a tick cdna library. this cdna codes for a preprotein of 166 amino acids, including a predicted signal peptide composed of 15 amino acids n-terminal to the mature amblin. the 151-amino-acid mature amblin contains 14 cysteines and two kunitz-like domains. it displays high sequence similarity with a tissue factor pathway inhibitor (tfpi), i ...200415527983
amblyomma americanum salivary gland homolog of nsec1 is essential for saliva protein secretion.soluble n-ethylmaleimide-sensitive factor attachment protein receptor proteins assemble in tight core complexes which promote fusion of carrier vesicles with target compartments. members of this class of proteins are expressed in all eukaryotic cells and distributed in distinct subcellular compartments. all vesicle transport mechanisms known to date have an essential requirement for a member of the sec1 protein family, including the nsec1 in regulated exocytosis. a homolog of nsec1 was cloned an ...200415504350
rickettsia parkeri in amblyomma triste from uruguay.our goal was to detect whether spotted fever group rickettsia are found in the suspected vector of rickettsioses, amblyomma triste, in uruguay. rickettsia parkeri was detected in a. triste, which suggests that this species could be considered a pathogenic agent responsible for human rickettsioses in uruguay.200415496258
morphological characterization of the ovary and vitellogenesis dynamics in the tick amblyomma cajennense (acari: ixodidae).in this work we describe the internal morphology of the female reproductive system of the cayenne tick amblyomma cajennense. this system is represented by a panoistic ovary, which lacks nurse cells in the germarium. this ovary consists of a single tube, in which a large number of oocytes develop asynchronously, thus accompanying the processes of yolk deposition in the oocytes. the oocytes were classified into stages that varied from i to v, according to: cytoplasm appearance, presence of the ger ...200415482894
amblyomma variegatum and acute bovine dermatophilosus. 198615462727
[rickettsia africae, the agent of african tick-bite fever: an emerging pathogen in the west indies and reunion island (indian ocean)].rickettsia africae is the agent of african tick bite fever, an emerging disease transmitted by amblyomma ticks in sub-saharan africa. in 1998, we reported the first documented case of r. africae in the new world, in a patient who had returned from guadeloupe. in order to confirm the presence of r. africae in the west indies, entomologic surveys were conducted from 1999 to 2003 to collect amblyomma, which are considered as potential vectors and reservoirs of the bacteria. ticks were used as epide ...200415462202
[amblyomma diemeniae, a new reptilian tick from australia, with observations on variant formations of the clava in the genus amblyomma]. 195015431890
serological characteristics of a pathogenic rickettsia occurring in amblyomma maculatum. 194915398100
detection of rickettsia africae in patients and ticks along the coastal region of cameroon.rickettsia africae was identified in seven (6%) of 118 patients with acute fevers of unknown etiology proven not to be malaria or typhoid fever from clinics along the coastal region of cameroon by polymerase chain reaction (pcr) amplification and sequencing of the citrate synthase (glta) and outer membrane protein a (ompa) genes of rickettsia. the majority (71%) of the patients were female. clinical manifestations included fever (100%), headache (71%), myalgia (71%), arthralgia (43%), pulmonary ...200415381820
some observations on the sero-prevalence of heartwater and tick infestation in zambian goats.a survey was carried out to define the distribution of heartwater in goats that originated from six districts in communal grazing semi-arid areas of zambia. a total of 181 samples (40.1%) out of 451 serum samples from adult goats were positive for ehrlichia ruminantium antibodies after screening using indirect map-1b antigen elisa technique with statistically significant differences (p < 0.01) between the six districts. out of 1 036 adult goats examined for tick infestation, 105 were infested by ...200415373339
susceptibility of mosquito and tick cell lines to infection with various flaviviruses.the genus flavivirus consists of more than 70 virus species and subtypes, the majority of which are transmitted by mosquitoes or ticks, although some have no known vector (nkv). the ability of these viruses to infect cultured cells derived from mosquito or tick species offers a useful insight into the suitability of such vectors to harbour and replicate particular viruses. we undertook a comparative study of the susceptibility of mammalian vero cells, a clonal mosquito cell line (c6/36) and rece ...200415347394
water relations in eggs of the lone star tick, amblyomma americanum, with experimental work on the capacity for water vapor absorption.this study shows that water stress is not countered in eggs of the lone star tick, amblyomma americanum (l.), using water vapor, and suggests involvement of liquid water as a developmental cue. eggs fail to maintain an equilibrium water content in subsaturated air, hence, gain not equal to loss, with net water losses occurring at relative humidities near saturation and these eggs exhibit a three-fold drop in viability, but not incubation period, as compared to eggs held in saturated air. amblyom ...200415347026
ehrlichia prevalence in amblyomma americanum, central texas. 200415338551
disease agents in amblyomma americanum from northeastern georgia.amblyomma americanum (lone star tick) is known or suspected to vector several organisms that are implicated as human pathogens, including ehrlichia chaffeensis, e. ewingii, and borrelia lonestari. these three agents have also been detected in white-tailed deer (odocoileus virginianus). because northeastern georgia has a high abundance of both lone star ticks and white-tailed deer, and one of these organisms, e. chaffeensis, is already known to be endemic in the area, we assayed individual adult ...200415311471
first record of immature stages of amblyomma tigrinum (acari: ixodidae) on wild birds in chile.for the first time, larvae and nymphs of amblyomma tigrinum ticks were found on three species of wild birds (zenaida auriculata, callipepla californica and nothoprocta perdicaria) in chile. a significant higher number of a. tigrinum was found on fledglings of z. auriculata and n. perdicaria than on adults of these species of birds. a significant higher number was also observed on n. perdicaria living in non-irrigated areas as compared with irrigated areas. infestation levels were 6.5, 6.3 and 10 ...200415285147
amblyomma cajennense ticks induce immediate hypersensitivity in horses and donkeys.since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. amblyomma cajennense is an important tick-borne disease vector in the neotropical region and horses maintain it in domestic environments. in the present work intradermal testing of a. cajennense tick exposed horses and donkeys using crude tick antigens was used to ev ...200415285143
ticks (acari: ixodidae) parasitizing wild carnivores in phu khieo wildlife sanctuary, thailand.ixodid ticks were collected and identified from 8 wild carnivore species in phu khieo wildlife sanctuary, northeastern thailand. six tick species belonging to 4 genera were recovered and identified from 132 individuals. these included amblyomma testudinarium (n = 36), haemaphysalis asiatica (n = 58), h. hystricis (n = 31), h. semermis (n = 3), rhipicephalus haemaphysaloides (n = 3), and ixodes granulatus (n = 1). leopard cats (prionailurus bengalensis) (n = 19) were infested with 4 tick species, ...200415270119
ectoparasites of gray squirrels in two different habitats and screening of selected ectoparasites for bartonellae.gray squirrels, sciurus carolinensis, were livetrapped in 2 different habitat types, woodland (67 squirrels) and parkland (53 squirrels), in southeastern georgia. ectoparasites were recovered from anesthetized squirrels and compared between hosts from the 2 habitats. because of the absence of low vegetation in parkland habitats, it was hypothesized that the ectoparasite fauna, especially ticks and chiggers, would be more diverse on woodland squirrels. the results were generally in agreement with ...200415270090
a new type of antimicrobial protein with multiple histidines from the hard tick, amblyomma hebraeum.a novel 11 kda antimicrobial protein, named as hebraein, and having a unique amino acid sequence, was purified from the hemolymph of fed female amblyomma hebraeum ticks. a full-length cdna clone encoding hebraein was isolated from a cdna library made from tick synganglia. hebraein consists of 102 amino acids, including 6 cysteine residues; has 9 histidines in its c-terminal domain that are mainly present as hx repeats; and has no significant similarity to any known protein. the secondary structu ...200415247144
effects of granular carbaryl application on sympatric populations of ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs.a single application of granular carbaryl approaching the lowest recommended rate to the shrub layer of a forested area in late spring significantly reduced the abundance of ixodes scapularis say nymphs throughout their peak activity period, but had little effect on amblyomma americanum l. nymphs. factors influencing the efficacy of the application are discussed. the possible explanations for the lack of efficacy of granular carbaryl against a. americanum, including behavior, formulation, and ap ...200015218915
spotted fever group rickettsiae from ticks captured in sudan.ticks were collected from ruminants in various areas of sudan in 1998 and 2000. primer pairs of rickettsial citrate synthase gene (glta) and a spotted fever group (sfg) rickettsial 190-kda surface antigen gene (rompa), respectively, were used for identification. polymerase chain reaction (pcr)-positive products were used for dna sequencing. the glta gene was detected in 55% of the ticks examined (57/104). among the 57 ticks studied, 19 were positive for the rompa gene. thus, 18% of the ticks exa ...200415218219
cross-reactivity between antigens from amblyomma cajennense and a. hebraeum (acari: ixodidae).laboratory animals exposed to feeding ticks develop resistance which is reflected by a decline in tick engorgement weight, egg-laying by adults and reduced egg viability. serum antibodies from these hosts and their reaction with tick antigens have been detected by different methods, including precipitation techniques, immunofluorescent techniques, elisa and western blots. however, little is known about the effects of antibodies on ticks that engorge on resistant hosts, or which tissues of the ti ...200415214694
cutaneous hypersensitivity induced in rabbits by extracts of the tick amblyomma cajennense (acari: ixodidae).the cutaneous hypersensitivity test was used to correlate host resistance to ticks and type of reactions elicited by aomblyomma cajennense (fabricius, 1787) tick extract in rabbits. rabbits were divided into 3 groups of 2 animals each: naive, pre-infested and control. cutaneous hypersensitivity was induced by intradermal inoculation of 25 microg extract in 0.03 ml of phosphate buffered saline (pbs) in rabbit ears. control rabbits were inoculated with pbs only. the ear thickness was measured with ...200415214693
a proteomics approach to characterizing tick salivary secretions.the saliva of ticks contains a complex mixture of bioactive molecules including proteins that modulate host responses ensuring successful feeding. the limited amount of saliva that can be obtained from ticks has hampered characterization of salivary proteins using traditional protein chemistry. recent improvements in two-dimensional gel electrophoresis, mass spectrometry, and bioinformatics provide new tools to characterize small amounts of protein. these methods were employed to characterize sa ...200415198089
an updated list of the ticks of ghana and an assessment of the distribution of the ticks of ghanaian wild mammals in different vegetation zones.twenty one species of ticks belonging to five genera of the family ixodidae (order acari, sub-order ixodida) - amblyomma, haemaphysalis, hyalomma, ixodes and rhipicephalus (including the sub-genus rhipicephalus (boophilus)) - were collected from 1260 mammals, representing 29 species, 14 families and 6 orders, in four vegetation zones in ghana during the period 1971-1978. four other species were collected from humans in 1977. in all, eight species appeared to be new records for ghana: amblyomma t ...200415191626
human otoacariasis: a retrospective study from an area of sri lanka.intra-aural ticks were present in 870 (15.2%) of 5714 patients who reported with ear-related complaints to the ear, nose and throat ward at ratnapura hospital, sabaragamuwa province, sri lanka, from january 2000 to december 2001. a retrospective study of 383 of these otoacariasis cases showed that the majority (70.8%) of surgically-removed ticks were nymphal amblyomma integrum, together with nymphal and adult rhipicephalus haemaphysaloides, r. sanguineus, hyalomma brevipunctata, h. marginatum, a ...200415186938
molecular evidence for a spotted fever group rickettsia species in the tick amblyomma longirostre in brazil.two amblyomma longirostre adult male ticks were collected from a brazilian porcupine coendou prehensilis l. in the state of rondonia, western amazon, brazil. the two ticks were pooled for dna extraction and tested for the presence of rickettsial dna by amplifying portions of the glta, 17-kda, ompa, and ompb rickettsial genes by polymerase chain reaction (pcr). portions of the four genes were amplified from the sample and subsequently sequenced. these results indicated the presence of a rickettsi ...200415185961
study of the seasonal dynamics, life cycle, and host specificity of amblyomma aureolatum (acari: ixodidae).in the first part of this study, monthly infestation by ticks was evaluated on dogs from december 2000 to november 2002 in the rural area of taiaçupeba, são paulo. adults of amblyomma aureolatum (pallas) were found on dogs in all months, with a mean prevalence per month of 46.9 +/- 15.7% (range, 25-80%). the mean tick relative abundance per month was 2.4 +/- 2.7 ticks (range, 0.5-14 ticks), and the mean tick mean intensity per month was 4.7 +/- 4.2 ticks (range, 1.5-23.3 ticks). no a. aureolatum ...200415185932
phylogenetic analysis of the francisella-like endosymbionts of dermacentor ticks.bacterial endosymbionts with significant homology to francisella tularensis (gamma-proteobacteria) have been described from at least five species of ticks in three different genera, including two north american dermacentor species [d. andersoni stiles and d. variabilis (say)]. the evolutionary relationships among the francisella-like endosymbionts (fle) from different hosts and between fle and the arthropod-borne pathogen f. tularensis are not known. a 1,169-base fragment of the 16s rdna and a 7 ...200415185926
development of a novel self-medicating applicator for control of internal and external parasites of wild and domestic animals.four trials, three in the united states and one in south africa, were conducted to evaluate the potential value of a novel self-medicating applicator in the passive control of gastrointestinal nematodes in cattle and deer, and of files and ticks on cattle using oil-based treatments. the results of the trials demonstrated that this applicator is an effective and practical device for the passive treatment of both deer and cattle for trichostrongyle infections using the endectocide, moxidectin (cyd ...200415185574
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.partially fed adult female amblyomma hebraeum ticks were injected with 20-hydroxyecdysone (20e; up to 43 microg/g body weight (bw)), juvenile hormone iii (jh iii; up to 100 microg/g bw), bovine insulin (up to 2000 mu/g bw), or triiodothyronine (up to 200 ng/g bw) in an attempt to stimulate vitellogenesis. of these, only 20e stimulated synthesis and release of vitellogenin (vg). immunoblot analysis revealed that vg-synthesis occurred in the fat body. however, consistent with earlier observations ...200415183281
[relative abundance of amblyomma spp. (acari: ixodidae) in bovines (bos taurus and b. indicus) from costa rica].the research describe the big amount of ticks of the amblyomma genus, found on bovines through monthly samplings carried out in ten farms in eight ecological zones (ez) of costa rica. ticks larger than 4 mm were picked up from the right side of the animals during the visit. the study compiled meteorological information for some farms located in the experiment, showing that the most fluctuant variable is rainfall. the most important amblyomma species found was a. cajennense. amblyomma nymphs were ...200315162737
ehrlichia ruminantium seroprevalence in domestic ruminants in ghana; i. longitudinal survey in the greater accra region.serum samples collected monthly over a 34-month period from cattle, sheep and goats in the greater accra region of ghana were tested for antibodies to ehrlichia (previously cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive elisa (pc-elisa). maternal antibodies, detected in about half of animals followed from under 1 month old, declined to negative levels within 2-4 months. amblyomma variegatum tick vectors were present on livestock in rural areas throughout the y ...200415145496
life cycle of amblyomma cooperi (acari: ixodidae) using capybaras (hydrochaeris hydrochaeris) as hosts.the life cycle of amblyomma cooperi was evaluated under laboratory conditions testing different host species. larval infestations were performed on chickens (gallus gallus) and capybaras (hydrochaeris hydrochaeris). nymphal infestations were performed on g. gallus, h. hydrochaeris, guinea pigs (cavia porcellus) and wild mice (calomys callosus). infestations by adult ticks were performed only on capybaras. all free-living stages were observed in darkness at 27 degrees c and rh 85%. capybaras were ...200415139274
monthly dynamics of ticks (acari:ixodida) infesting n'dama cattle in the republic of guinea.the occurrence of ixodid ticks on n'dama cattle was studied in the republic of guinea between june 1994 and may 1995. monthly tick collections were performed on 80 animals from 14 villages located in dabola, kouroussa and dinguiraye prefectures. a total of 19,804 ticks was collected and classified using standard taxonomic keys. the following tick species were identified: amblyomma variegatum, hyalomma marginatum rufipes, hyalomma trunctum, hyalomma nitidum, rhipicephalus lunulatus, rhipicephalus ...200415139086
disease survey of free-ranging grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia.samples from 17 free-ranging hunter-killed grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia, were collected during june-august 1999. all 17 deer appeared to be in good condition at the time of death. gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. serologic tests were positive for antibodies against bovine respiratory ...200415137493
glycerophosphodiester phosphodiesterase gene (glpq) of borrelia lonestari identified as a target for differentiating borrelia species associated with hard ticks (acari:ixodidae).a glpq ortholog was identified in dna from borrelia lonestari-positive amblyomma americanum, providing further evidence that b. lonestari is more closely related to the relapsing fever group spirochetes than to borreliae that cause lyme disease. this finding provides a basis for developing diagnostic assays to differentiate species of borrelia transmitted by hard ticks.200415131225
the distribution and ecological 'preferences' of the tick amblyomma cajennense (acari: ixodidae), an ectoparasite of humans and other mammals in the americas.the distribution and ecological 'preferences', in the nearctic and neotropical regions, of the prominent, pathogen-carrying tick amblyomma cajennense (fabricius) were reviewed, on the basis of the published literature, satellite imagery, and the examination of several tick collections. the tick has been collected from the southern u.s.a. (texas and florida) to northern argentina, but is probably absent from uruguay and southern brazil (the few records of the species in these areas probably repre ...200415119974
detection of pathogenic ehrlichia in ticks collected at acquisition sites of human ehrlichiosis in missouri.we collected 385 ticks from sites in missouri associated with human monocytic ehrlichiosis. using pcr, we detected e. chaffeensis or e. ewingii in 2 of 19 pools of adult amblyomma americanum, 0 of 32 pools of dermacentor variabilis, and 6 (18%) of 39 pools of unspeciated nymphal ticks from 3 of 6 sites associated with disease and one site not associated with disease. we also detected a variant of a. phagocytophila in one nymph pool.200415119113
species of ticks on camels and their seasonal population dynamics in eastern ethiopia.a study was conducted to identify the species of ticks found on camels (camelus dromedarius) and their seasonal population dynamics in eastern ethiopia. collection and identification of the ticks were undertaken at 2-month intervals from december 1997 to august 1999. on each occasion, all the visible adult ticks were collected from one side of the body of each of the same 17 camels. the most abundant species of ticks on the camels were rhipiephalus pulchellus (85.2%), hyalomma dromedarii (5.9%), ...200415080539
a monitoring study on the prevalence of dermatophilosis and parafilariosis in cattle in a smallholder semi-arid farming area in zimbabwe.the prevalences of dermatophilosis and parafilariosis were monitored for one year in cattle in sanyati, a semi-arid smallholder farming area in zimbabwe. the prevalence of dermatophilosis differed (p < 0.05) with season and among calves, cows, oxen and bulls. in bulls and cows, dermatophilosis lesions were localized mainly to the inguinal regions and between the front limbs. the prevalence and morbidity of dermatophilosis infection were significantly higher (p < 0.05) during the wet season than ...200415080537
two feeding-induced proteins from the male gonad trigger engorgement of the female tick amblyomma hebraeum.most female ixodid ticks, once mated, feed to repletion within 6-10 days. previous studies indicate that an engorgement factor (ef), passed to the female during copulation, may be the stimulus for engorgement. here, we show that extracts of the testis/vas deferens of fed (but not unfed) male amblyomma hebraeum contain ef bioactivity when injected into the hemocoel of feeding virgins. we have produced recombinant proteins (recproteins) from 28 feeding-induced genes in the male gonad and have iden ...200415069191
comparative activity of deet and ai3-37220 repellents against the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.the repellents n,n-diethyl-3-methylbenzamide (deet) and racemic 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (ai3-37220) were evaluated using two different laboratory bioassays to determine their relative effectiveness against host-seeking nymphs of the blacklegged tick, ixodes scapularis say, and the lone star tick, amblyomma americanum (l.). in a petri dish bioassay, ticks were released within a ring of repellent on a horizontal filter paper disk. in the second bioassay, ticks were allowed ...200415061285
occurrence of the gulf coast tick (acari: ixodidae) on wild and domestic mammals in north-central oklahoma.parasitic life stages of amblyomma maculatum koch were collected from domestic cattle and several species of wild mammals during a 3.5-yr study (may 1998-october 2001) in north-central oklahoma. adult ticks were the predominant life stage collected from cattle, white-tailed deer, coyotes, and raccoons, whereas only immature ticks were collected from cotton rats and white-footed mice. the prevalence of adult a. maculatum on white-tailed deer (n = 15) examined in june, july, and august 1998 was 80 ...200415061275
ehrlichia ruminantium grows in cell lines from four ixodid tick genera.continuous cell lines from the ticks amblyomma variegatum, boophilus decoloratus, boophilus microplus, hyalomma anatolicum anatolicum, ixodes scapularis, ixodes ricinus and rhipicephalus appendiculatus were tested for ability to support growth of the rickettsial pathogen ehrlichia (previously cowdria) ruminantium. five e.ruminantium isolates, from west africa, south africa and the french west indies, were used. twelve tick cell lines were inoculated with e.ruminantium derived either from culture ...200415053931
amblyomma americanum salivary glands: double-stranded rna-mediated gene silencing of synaptobrevin homologue and inhibition of pge2 stimulated protein secretion.protein secretion into the saliva from the tick salivary glands is due to exocytosis of vesicular membrane bound granular material regulated by snare complex proteins after salivary gland stimulation by pge2 [insect biochem. mol. biol. 32 (2002) 1711]. proteins associated with vesicles (v-snares) are essential components of the exocytotic process. synaptobrevin is a key v-snare in all secreting cells studied to date. a vesicle-associated synaptobrevin cdna fragment homologue from the salivary gl ...200415041024
how much pilocarpine contaminates pilocarpine-induced tick saliva?pilocarpine is often applied or injected into ticks to induce salivation, and the resulting saliva used to test for various pharmacological, biochemical and immunological activities. to measure the amount of pilocarpine in pilocarpine-induced tick saliva, an hplc-ms/ms method, based on capillary strong cation exchange chromatography online with an ion trap mass spectrometer, was used to measure pilocarpine in the pg to ng range. results indicate large concentrations of pilocarpine in ixodes scap ...200415009442
first culture isolation of borrelia lonestari, putative agent of southern tick-associated rash illness.southern tick-associated rash illness (stari) is a lyme disease-like infection described in patients in the southeastern and south-central united states, where classic lyme disease is relatively rare. stari develops following the bite of a lone star tick (amblyomma americanum) and is thought to be caused by infection with an "uncultivable" spirochete tentatively named borrelia lonestari. in this study, wild lone star ticks collected from an area where b. lonestari is endemic were cocultured in a ...200415004069
rickettsia parkeri: a newly recognized cause of spotted fever rickettsiosis in the united states.ticks, including many that bite humans, are hosts to several obligate intracellular bacteria in the spotted fever group (sfg) of the genus rickettsia. only rickettsia rickettsii, the agent of rocky mountain spotted fever, has been definitively associated with disease in humans in the united states. herein we describe disease in a human caused by rickettsia parkeri, an sfg rickettsia first identified >60 years ago in gulf coast ticks (amblyomma maculatum) collected from the southern united states ...200414999622
amblyomma aureolatum and ixodes auritulus (acari: ixodidae) on birds in southern brazil, with notes on their ecology.between january 1999 and december 2000, 876 bird specimens were captured in three different ecological environments from the reinhard maack park, curitiba, state of paraná, southern brazil. a total of 142 birds (16.2%) were infested with amblyomma aureolatum (pallas 1772) (n=699) and/or ixodes auritulus neumann, 1904 (n=18) ticks. questing a. aureolatum nymphs (n=2) and adults (n=5) were also collected from the soil and the vegetation. none of the i. auritulus were collected off-host. we collect ...200314974693
modulation of human lymphocyte proliferation by salivary gland extracts of ixodid ticks (acari: ixodidae): effect of feeding stage and sex.ixodid ticks remain attached to their hosts for several days to weeks. during this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. in our study a stimulatory or inhibitory effect of salivary gland extracts (sge) of unfed and partially fed female ixodes ricinus (linnaeus, 1758), female and male amblyomma variegatum (fabricius, 1794) and rhipicephalus appendiculatus neumann, 1901 ticks on human lymphocyte proliferatio ...200314971600
[mexican amblyomma castanedai n. sp. (ixodidae)]. 195214957782
[a note on the amblyomma astrion dönitz 1909]. 195114894811
tick paralysis; implicating amblyomma maculatum. 195114806800
[contribution to the study of the teratology of ixodids; 2 monsters obtained spontaneously in a strain of amblyomma nuttalli dönitz 1909]. 194914771470
evaluation of transovarial transmission and transmissibility of ehrlichia chaffeensis (rickettsiales: anaplasmataceae) in amblyomma americanum (acari: ixodidae).it has long been assumed that ehrlichia chaffeensis (anderson, dawson & wilson), is not transmitted transovarially in the lone star tick vector amblyomma americanum (l.). to test this hypothesis, three beagle dogs, canis familiaris (l.) (carnivora: canidae), were subcutaneously infected with e. chaffeensis (arkansas strain). uninfected nymphal lone star ticks were placed on the infected dogs and allowed to feed to repletion. these nymphal ticks were allowed to molt, and five of five adult female ...200314765684
life cycle and host specificity of amblyomma triste (acari: ixodidae) under laboratory conditions.we report biological data of two generations of amblyomma triste in laboratory and compared the suitability of different host species. infestations by larval and nymphal stages were performed on guinea pigs (cavia porcellus), chickens (gallus gallus), rats (rattus norvegicus), rabbits (oryctolagus cuniculus), wild mice (calomys callosus), dogs (canis familiaris) and capybaras (hydrochaeris hydrochaeris). infestations by adult ticks were performed on dogs, capybaras and rabbits. tick developmenta ...200314756395
evaluation of a prototype ehrlichia chaffeensis surveillance system using white-tailed deer (odocoileus virginianus) as natural sentinels.the natural history of ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, includes the lone star tick (lst, amblyomma americanum) as a vector and white-tailed deer (wtd; odocoileus virginianus) as both a natural reservoir of e. chaffeensis and a major host of lst. the goal of the current study was to implement and evaluate a prototype surveillance system to delineate the geographic distribution of e. chaffeensis using wtd as natural sentinels. to accomplish this goa ...200314733672
rickettsia species infecting amblyomma cooperi ticks from an area in the state of são paulo, brazil, where brazilian spotted fever is endemic.owing to the potential role of the tick amblyomma cooperi in the enzootic cycle of rickettsia rickettsii, the etiologic agent of brazilian spotted fever (bsf), this study evaluated infection by rickettsia species in a. cooperi ticks collected from an area in brazil where bsf is endemic. among a total of 40 a. cooperi adult ticks collected in an area of bsf endemicity in the state of são paulo, pcr analysis detected dna of rickettsia bellii in 16 ticks (40%), and 3 other ticks (7.5%) were positiv ...200414715737
survey of ticks collected in mississippi for rickettsia, ehrlichia, and borrelia species.from november 1999 through october 2000, we tested ticks collected from vegetation as well as from deer, dogs, and humans for spotted fever group (sfg) rickettsiae, ehrlichia chaffeensis, and borrelia spp. spirochetes. a total of 149 adult ticks representing four species was collected from 11 collection sites from southwestern to northern mississippi. amblyomma americanum was most commonly collected (n=68), followed by ixodes scapularis (n=53). the bird tick, ixodes brunneus (usually rare), was ...200314714667
two novel non-cationic defensin-like antimicrobial peptides from haemolymph of the female tick, amblyomma hebraeum.two non-cationic defensin-like antimicrobial peptides, named amblyomma defensin peptide 1 and amblyomma defensin peptide 2, were identified from the hard tick, amblyomma hebraeum, by a combination of suppression subtractive hybridization for differentially expressed genes and proteomics. cdna clones encoding each of these two defensin-like antimicrobial peptides were isolated from the differentially expressed cdna library of the tick synganglia (central nervous system). the preproproteins deduce ...200414705963
dna evidence of borrelia lonestari in amblyomma americanum (acari: ixodidae) in southeast missouri.amblyomma americanum collected near lake wappapello, missouri, tested positive for borrelia lonestari using polymerase chain reaction and sequence analyses of b. lonestari 16s rrna and flagellin (flab) genes. twelve pools containing a total of 214 nymph or adult ticks contained evidence of infection with b. lonestari (minimum prevalence 5.6%). these data suggest that persons in southeast missouri are at risk for exposure to b. lonestari after a. americanum tick bite, a possible cause of erythema ...200314680133
transstadial transfer of west nile virus by three species of ixodid ticks (acari: ixodidae).larvae and/or nymphs of four species of ixodid ticks, ixodes scapularis say, amblyomma americanum (l.), dermacentor andersoni stiles, and dermacentor variabilis say, were fed to completion on laboratory hamsters or mice which had been inoculated with a west nile (wn) virus isolate from culex pipiens l. captured in connecticut usa. maximum titers in mice and hamsters were approximately 5 and two logs, respectively, lower than recorded (10 logs) in a naturally infected american crow, corvus brachy ...200314680122
meteorologically mediated diurnal questing of ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs.questing ixodes scapularis say and amblyomma americanum (l.) nymphs were collected in the field by drag sampling to determine whether ticks would be collected in greater numbers during certain times of the day and under certain ambient meteorological conditions. ticks were collected hourly for 16 h on 4 d and counts were contrasted with simultaneous measurements of ambient temperature and relative humidity, and with similar measurements made within the leaf litter. peak numbers of questing i. sc ...200314680102
evidence of borrelia lonestari dna in amblyomma americanum (acari: ixodidae) removed from humans.we used a nested pcr with borrelia flagellin gene (flab) primers and dna sequencing to determine if borrelia lonestari was present in amblyomma americanum ticks removed from military personnel and sent to the tick-borne disease laboratory of the u.s. army center for health promotion and preventive medicine. in our preliminary investigation, we detected borrelia sequences in 19 of 510 a. americanum adults and nymphs from ft. a. p. hill, va. during the 2001 tick season, the flab primers were used ...200314662940
seasonal dynamics of the cayenne tick, amblyomma cajennense on horses in brazil.the population dynamics of all stages of the cayenne tick, amblyomma cajennense (fabricius) (acari: ixodidae) on horses was evaluated over a period of 2 years in the district of pedro leopoldo, state of minas gerais, brazil. every 14 days, the left side of 20 horses was brushed for collection of immature stages; counts of adults were also undertaken. infestation by larvae was detected from april to august, whereas nymphs were observed from june to october. infestation by adults was detected thro ...200314651655
in vitro assays for repellents and deterrents for ticks: differing effects of products when tested with attractant or arrestment stimuli.most in vivo and in vitro tests with repellents or deterrents against ticks have not considered which sensory channel is being targeted. we have recorded the responses of two hard tick species (acari: ixodidae) in vitro to determine if such products can disrupt the perception of an attractant in a repellent assay or the perception of an arrestment stimulus in a deterrent assay. ethyl butylacetylaminopropionate (ebaap), n,n-diethyl-methyl-benzamide (deet), permethrin and indalone were chosen to t ...200314651650
acquired resistance of horses to amblyomma cajennense (fabricius, 1787) ticks.acquired immunity of horses to larvae, nymphs and adults of the amblyomma cajennense tick was evaluated through three consecutive experimental infestations of tick-bite naïve hosts. data from these infestations were compared to those from field-sensitized horses and donkeys. it was observed that tick-bite naïve horses developed a low level of resistance after two infestations as shown by a significant decrease in larval yield and a tendency for lower engorged weight of nymphs during third infest ...200314637029
comparing the detection of exposure to ehrlichia ruminantium infection on a heartwater-endemic farm by the pcs20 polymerase chain reaction assay and an indirect map1-b enzyme linked immunosorbent assay.detection of heartwater is not always easy especially because all the serological assays so far available either have poor sensitivity or specificity. the indirect map-1b elisa has been reported to be the most specific test for heartwater, although it does also detect antibodies to some closely related ehrlichial agents. this study was undertaken to compare two methods for the detection of heartwater infection caused by the ehrlichial agent ehrlichia (cowdria) ruminantium. fifteen cattle on a he ...200314621319
ticks (ixodida: ixodidae) parasitising humans in uruguay.during routine collections between november 1999 and november 2002, three species of tick (amblyomma tigrinum, amblyomma triste and rhipicephalus sanguineus) were found on humans in southern uruguay. the finding of r. sanguineus and a. triste on humans is of particular concern because these tick species may be involved in the transmission of the pathogens causing human rickettsioses, a type of disease already known to occur in uruguay.200314613636
a cautionary note: survival of nymphs of two species of ticks (acari: ixodidae) among clothes laundered in an automatic washer.host-seeking ticks often remain on clothing of persons returning home from work or recreation in tick habitats, and can pose at least a temporary risk to people and pets in these homes. laundering clothing has been one of the recommendations to reduce tick exposure. host-seeking lone star tick, amblyomma americanum (l.), and blacklegged tick, ixodes scapularis say, nymphs confined in polyester mesh packets, were included with laundry in cold, warm, and hot wash cycles of an automatic clothes was ...200314596290
experimental infection of lone star ticks, amblyomma americanum (l.), with rickettsia parkeri and exposure of guinea pigs to the agent.the maculatum agent, rickettsia parkeri (a member of the spotted fever group rickettsiae), was inoculated into a colony of the lone star tick, amblyomma americanum, and followed for two tick generations. in addition, guinea pigs were exposed to the agent by direct injection and by feeding infected ticks on them. eighty (53%) of 150 nymphal a. americanum that were inoculated with suspensions of r. parkeri were positive by hemolymph test and fluorescent antibody test for rickettsial infection when ...200314596284
hosts and distribution of amblyomma auricularium (conil 1878) and amblyomma pseudoconcolor aragão, 1908 (acari: ixodidae).collections of amblyomma auricularium (conil 1878) and a. pseudoconcolor aragão, 1908 are discussed in relation to distribution and hosts. three tick collections (two from argentina and a third from the usa) house a total of 574 a. auricularium (307 males, 162 females, 73 nymphs and 32 larvae) and 179 a. pseudoconcolor (96 males, 74 females, 4 nymphs and 5 larvae). apart from an adult a. pseudoconcolor found on a bird, nothura maculosa temminck, 1815, all ticks were found on mammals. the great m ...200314580065
attraction of amblyomma variegatum (ticks) to the attraction-aggregation-attachment-pheromone with or without carbon dioxide.the responses of adult amblyomma variegatum ticks released from various distances to different doses of the synthetic attraction-aggregation-attachment pheromone (aaap) (made up of orthonitrophenol, methyl salicylate and nonanoic acid in paraffin oil), dispensed from the center of circular field plots, were studied in the presence or absence of elevated levels of co2. up to 90% of the ticks released were attracted to the pheromone source in the presence of co2 within 3h. co2 alone was unattracti ...200314580064
control of ixodes scapularis and amblyomma americanum through use of the '4-poster' treatment device on deer in maryland.deer self-treatment devices ('4-posters') were evaluated for their efficacy in reducing populations of blacklegged ticks, ixodes scapularis, and lone star ticks, amblyomma americanum. at each of three locations in maryland, 25 '4-posters' were operated in study areas of approximately 5.18 km2. populations of host-seeking ticks were monitored by flagging of treated areas and similar untreated control areas without '4-posters.' from 1998 to 2002 the percent mortalities achieved were 69, 75.8 and 8 ...200214570143
progress towards the eradication of amblyomma variegatum from the caribbean.progress in the caribbean amblyomma program (cap) is reviewed since its inception in 1995 when regional eradication activities for amblyomma variegatum ticks were initiated using bayticol pour-on. technical achievements in the various islands were slow initially, and showed a wide diversity in attaining eradication targets. st. kitts, considered as a model program. eliminated the tropical bont tick (tbt) from most of the island in less than 3 years. however, the elimination of very low numbers o ...200214570141
immunogenicity of ehrlichia ruminantium grown in tick cell lines.ehrlichia (previously cowdria) ruminantium, the pathogen which causes heart-water in domestic and wild ruminants, can now be propagated in cell lines from one vector (amblyomma variegatum) and five non-vector (ixodes scapularis, i. ricinus, boophilus decoloratus, b. microplus and rhipicephalus appendiculatus) tick species. e. ruminantium isolates from west and south africa and the caribbean vary in their cell line preference, growth patterns and immunogenic capability. in laboratory trials, cert ...200214570129
how specific are host-produced kairomones to host-seeking ixodid ticks?ixodid ticks respond to host-produced substances (kairomones) that influence the ticks' host-finding behavior. in the laboratory adult blacklegged ticks, ixodes scapularis say, lone star ticks, amblyomma americanum l., and american dog ticks, dermacentor variabilis (say) became akinetic on residues rubbed from their principal hosts (deer for the former two species and dogs for the latter). however, arrestment also occurred when adults of these species were tested using the same method bioassay, ...200214570126
an inhibitor of thrombin-stimulated blood platelet aggregation from the salivary glands of the hard tick amblyomma variegatum (acari: ixodidae).the tropical bont tick, amblyomma variegatum can cause intense skin irritation and inflammation and bites that often develop into septic wounds or abscess in their host. crude salivary gland extract (sge) of partially engorged a. variegatum females as well as sge protein fractions purified by three-step reverse phase hplc procedure were tested for their anti-aggregatory effect on isolated human blood platelets stimulated with thrombin and compared with the effect of recombinant hirudin. at conce ...200214570120
a proteomics approach to characterizing tick salivary secretions.the saliva of ticks contains a complex mixture of bioactive molecules including proteins that modulate host responses ensuring successful feeding. the limited amount of saliva that can be obtained from ticks has hampered characterization of salivary proteins using traditional protein chemistry. recent improvements in two-dimensional gel electrophoresis, mass spectrometry, and bioinformatics provide new tools to characterize small amounts of protein. these methods were employed to characterize sa ...200214570118
the argasidae, ixodidae and nuttalliellidae (acari: ixodida): a world list of valid tick names.the world's argasid tick fauna comprises 183 species in four genera, namely argas, carios, ornithodoros and otobius in the family argasidae. the ixodid tick fauna consists of 241 species in the genus ixodes and 442 species in the genera amblyomma, anomalohimalaya, bothriocroton, cosmiomma, dermacentor, haemaphysalis, hyalomma, margaropus, nosomma, rhipicentor and rhipicephalus in the family ixodidae, with the genus boophilus becoming a subgenus of the genus rhipicephalus. the family nuttallielli ...200214570115
american canine hepatozoonosis.american canine hepatozoonosis (ach) is a tick-borne disease that is spreading in the southeastern and south-central united states. characterized by marked leukocytosis and periosteal bone proliferation, ach is very debilitating and often fatal. dogs acquire infection by ingesting nymphal or adult gulf coast ticks (amblyomma maculatum) that, in a previous life stage, ingested the parasite in a blood meal taken from some vertebrate intermediate host. ach is caused by the apicomplexan hepatozoon a ...200314557294
the fine structure of spermatids from the tick, amblyomma dissimili. 196114491069
the bont tick (amblyomma hebraeum), exotic vector of heartwater found in the united states. 196514323370
allergy in a horse due to amblyomma americanum. 196514296518
[a new species of amblyomma, parasite of madagascan tortoises: a. chabaudi n. sp. (acariens ixodidae)]. 196414250518
ticks (ixodidae) on migrating birds in egypt, spring and fall 1962.over a number of years studies have been carried out in egypt on the transport by migrating birds of ticks that may transmit pathogens of man and animals. in continuation of these investigations 11 036 birds migrating southwards through egypt were examined for ticks during the fall of 1962. the 881 infested birds (comprising 24 species and sub-species represented by 10 612 individuals) yielded 1442 ticks. tick-host relationships were similar to those of previous years except that in 1962 the pre ...196414163959
the laboratory rearing of amblyomma sparsum neumann, 1899. 196414124281
[observations on the morphology, biology and development of amblyomma compressum (macalister, 1872), the pangolin tick of west africa]. 196314011156
spermiogenesis in the tick, amblyomma dissimili, as revealed by electron microscopy. 196313973643
a fine-structure study on spermiogenesis in the tick amblyomma dissimill, with special reference to the development of motile processes. 196213973642
kohls gm: description of the female of dermacentor latus cooley and of amblyomma albopictum neumann (acarina-ixodidae). 196213879941
[ixodological notes. ix. the oval complex of the genus amblyomma]. 196113861961
[studies on the transmission of toxoplasma gondii. ii. note on the experimental transmission by the tick amblyomma cajennense]. 195813848246
[rectification of diagnosis: amblyomma tigrinum koch in place of amblyomma maculatum koch]. 195913836584
the possible role of ticks as vectors of leptospire. ii. infection of the ixodid ticks, dermacentor andersoni and amblyomma maculatum, with leptospira pomona. 195913806052
[apropos of amblyomma laticaudae warburton, 1933 (acarien ixodoidea) in new caledonia]. 196013739123
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