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host selection by questing female amblyomma maculatum koch, to cattle with feeding male ticks in southern texas.the feeding associations among male and female gulf coast ticks, amblyomma maculatum koch, were examined using archived data obtained from untreated free-ranging cattle pastured on native rangeland. there was significant evidence of a relationship between male and female tick presence on hosts (p-value <0.0001), suggesting that a. maculatum females will more frequently be attracted and attach to grazing cattle with feeding males than those without. seasonal data were tested to develop prediction ...201020627588
social network structure and parasite infection patterns in a territorial reptile, the tuatara (sphenodon punctatus).we investigated whether the parasite load of an individual could be predicted by its position in a social network. specifically, we derived social networks in a solitary, territorial reptile (the tuatara, sphenodon punctatus), with links based on the sharing of space, not necessarily synchronously, in overlapping territories. tuatara are infected by ectoparasitic ticks (amblyomma sphenodonti), mites (neotrombicula spp.) and a blood parasite (hepatozoon tuatarae) which is transmitted by the tick. ...201020637210
rickettsial infections of dogs, horses and ticks in juiz de fora, southeastern brazil, and isolation of rickettsia rickettsii from rhipicephalus sanguineus ticks.the present study was performed in an area endemic for brazilian spotted fever (bsf) in juiz de fora, state of minas gerais, brazil, during the years 2007 and 2008, when fatal cases of bsf (caused by rickettsia rickettsii) were reported. adult ticks (acari: ixodidae) identified as rhipicephalus sanguineus (latreille) and amblyomma cajennense (fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (pcr). overall, 13.1% of the rh. sanguineus ticks and ...201020950356
acaricidal activity of the essential oils from eucalyptus citriodora and cymbopogon nardus on larvae of amblyomma cajennense (acari: ixodidae) and anocentor nitens (acari: ixodidae).the present study evaluated the acaricidal activity of essential oils from eucalyptus citriodora and cymbopogon nardus on non-engorged larvae of amblyomma cajennense and anocentor nitens. in order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (deltametrine). for each treatment, approximately 100 larvae of these ticks were placed ...201020640444
first record of amblyomma scalpturatum neumann (acari: ixodidae) in the states of paraná and roraima, brazil.amblyomma scalpturatum neumann has been reported in brazil in the northern (states of amazonas, pará and rondônia) and mid-western regions (states of mato grosso and mato grosso do sul). it has been found in association with large and medium sized mammals, as artiodactyla, perissodactyla, xenarthra and carnivora. in this paper, this tick species is reported for the first time in the brazilian states of paraná and roraima, southern and northern regions, respectively.201020676523
amblyomma triste (acari: ixodidae): new north american collection records, including the first from the united states.new distribution records for the neotropical tick, amblyomma triste koch, are identified from 27 specimens in 18 separate collections. these collections originated from six now recognized geographical foci in two states in the united states (cochise and santa cruz counties, arizona, and brewster and jeff davis counties, texas) and from import cattle, bos taurus l., presented for entry at the united states border and originating in three mexican states (coahuila, durango, and sonora). for at leas ...201020695268
a potential role for ixodid (hard) tick vectors in the transmission of lumpy skin disease virus in cattle.lumpy skin disease (lsd) is an economically important cattle disease. the disease is endemic in many african countries, but outbreaks have also been reported in madagascar and the middle east. the aim of this study was to investigate the potential role of ixodid (hard) ticks in the transmission of the disease. cattle were infected with a virulent, south african field isolate of lumpy skin disease virus (lsdv). three common african tick species (genera rhipicephalus, amblyomma and rhipicephalus ( ...201021114790
novel field assays and the comparative repellency of bioud(®) , deet and permethrin against amblyomma americanum.two new field bioassay methods were developed to compare the repellent activity of bioud(®) (containing 7.75% 2-undecanone), 98.1% deet and 0.5% permethrin against natural populations of nymphal amblyomma americanum (l.) (acari: ixodidae). in a cloth sheet assay, pieces of material measuring 41 × 58 cm, separately treated with one of the test materials or the appropriate solvent carrier, were placed at random on the ground and baited with dry ice for 1 h. mean numbers of ticks on repellent-treat ...201021118283
ticks (acari: ixodidae) from yellow armadillo, euphractus sexcinctus (cingulata: dasypodidae), in brazil's pantanal wetlands.tick species parasitizing yellow armadillo, euphractus sexcinctus, were recorded from october 2006 to october 2007 in pantanal. a total of 89 ticks were collected from 23 yellow armadillos. most ticks (n=50) were identified as amblyomma cajennense (fabricius) (32 males and 18 females). the only other species found was amblyomma parvum (aragão) (three females and two males). the remaining ticks were immatures of amblyomma (29 nymphs and five larvae). the prevalence of a. cajennense was 55%, the m ...201021120394
infrequency of rickettsia rickettsii in dermacentor variabilis removed from humans, with comments on the role of other human-biting ticks associated with spotted fever group rickettsiae in the united states.abstract from 1997 to 2009, the tick-borne disease laboratory of the u.s. army public health command (usaphc) (formerly the u.s. army center for health promotion and preventive medicine) screened 5286 dermacentor variabilis ticks removed from department of defense (dod) personnel, their dependents, and dod civilian personnel for spotted fever group rickettsiae using polymerase chain reaction and restriction fragment length polymorphism analysis. rickettsia montanensis (171/5286 = 3.2%) and ricke ...201021142953
rickettsia africae in amblyomma variegatum and domestic ruminants on eight caribbean islands.we used pcrs with omp a primers to determine if spotted fever group rickettsiae occurred in amblyomma variegatum from 6 caribbean islands. positive amplicons were obtained from ticks from the u.s. virgin islands (9/18; 50%), dominica (39/171; 30%), montserrat (2/5; 40%), nevis (17/34; 50%), st. kitts (46/227; 20%), and st. lucia (1/14; 7%). sequences for a convenience sample of reaction products obtained from a. variegatum on st. kitts (7), american virgin islands (4), montserrat (2), and st. lu ...201021158615
high-prevalence borrelia miyamotoi [scapin wild turkeys (meleagris gallopavo) in tennessee.during spring and fall 2009, 60 wild turkeys (meleagris gallopavo) harvested by tennessee hunters were surveyed for borrelia spp. by sampling their blood, tissue, and attached ticks. in both seasons, 70% of turkeys were infested with juvenile amblyomma americanum; one spring turkey hosted an adult female ixodes brunneus. polymerase chain reaction assays followed by dna sequencing indicated that 58% of the turkeys were positive for the spirochete borrelia miyamotoi, with tissue testing positive m ...201021175079
ticks infesting wildlife species in northeastern brazil with new host and locality records.from september 2008 to march 2010, 397 ticks (315 larvae, 33 nymphs, 23 females, and 26 males) were collected from captive and free-living wildlife species in northeastern brazil. six tick species were identified, including amblyomma auricularium (conil) on tamandua tetradactyla (l.), amblyomma dubitatum neumann on hydrochaeris hydrochaeris (l.), nectomys rattus (pelzen) and t. tetradactyla, amblyomma parvum aragão on t. tetradactyla, amblyomma rotundatum koch on boa constrictor l., chelonoidis ...201021175080
parasitisation and localisation of ticks (acari: ixodida) on exotic reptiles imported into poland.as a result of examinations, the following species of ticks have been found parasitising on python regius brought from africa to poland: amblyomma latum, amblyomma transversale, amblyomma spp., on varanus exanthematicus: amblyomma exornatum, amblyomma flavomaculatum, amblyomma latum, amblyomma nuttalli, amblyomma spp., on varanus salvator brought from indonesia to poland: amblyomma varanensis. there were 58 specimens of monitor lizard (v. salvator and v. exanthematicus) and 92 specimens of pytho ...201021186765
a case of amblyomma testudinarium tick bite in a korean woman.a case of tick bite was found in the inguinal region of a 74-year-old korean woman. she was attacked by the tick while working in her vegetable garden in the vicinity of mountain located in suncheon city, the southern coastal area of the korean peninsula. on admission she complained of mild discomfort and itching around the bite area. the causative tick was 23 mm long and had slender pedipalps. the scutum was quite ornate and had eyes at the edge. the genital aperture was located anterior to the ...201021234234
veterinary extension on sampling techniques related to heartwater research.heartwater, a tick-borne disease caused by ehrlichia ruminantium, is considered to be a significant cause of mortality amongst domestic and wild ruminants in south africa. the main vector is amblyomma hebraeum and although previous epidemiological studies have outlined endemic areas based on mortalities, these have been limited by diagnostic methods which relied mainly on positive brain smears. the indirect fluorescent antibody test (ifa) has a low specificity for heartwater organisms as it cros ...201021247042
confirmation of amblyomma americanum (acari: ixodidae) as a vector for cytauxzoon felis (piroplasmorida: theileriidae) to domestic cats.amblyomma americanum was confirmed as a competent vector in the transmission of cytauxzoon felis to domestic cats. infection with c. felis was produced and replicated in four domestic felines by the bite of a. americanum adults that were acquisition fed as nymphs on a domestic cat that survived cytauxzoonosis. numerous attempts to transmit c. felis with dermacentor variabilis at the same time were not successful. all cats upon which infected a. americanum were transmission fed exhibited disease ...201020939386
amblyomma aureolatum (acari: ixodidae) parasitizing margay (leopardus wiedii) in rio grande do sul.we report the finding of amblyomma aureolatum (acari: ixodidae) parasitizing margay (leopardus wiedii) in the locality of gravataí (29° 47' 12.9" s and 50° 53' 44.1" w; 241 m alt.), state of rio grande do sul, southern brazil. this is the first report of this species of ixodidae on margay in southern brazil. this finding indicates an increased number of hosts for this tick species.201020943026
a first record of amblyomma dissimile (acari: ixodidae) parasitizing the lizard ameiva ameiva (teiidae) in brazil.a non-engorged adult female amblyomma dissimile and two amblyomma sp. larvae were found parasitizing the lizard ameiva ameiva in the municipality of chapadinha, state of maranhão. this is the first record in the state of maranhão and fills a gap in the distribution of a. dissimile in brazil. the lizard a. ameiva represents a new host for a. dissimile, and also the first record of this tick species infesting lizards of the family teiidae in brazil.201021184707
new tick records in rondônia, western brazilian amazon.in the present study, we provide new tick records from vilhena municipality, in the southeast of the state of rondônia, northern brazil. ticks collected from a capybara, hydrochoerus hydrochaeris (linnaeus), were identified as amblyomma romitii tonelli-rondelli (1 female), and amblyomma sp. (1 larva). ticks collected from a harpy eagle, harpia harpyja (linnaeus), were identified as amblyomma cajennense (fabricius) (16 nymphs) and haemaphysalis juxtakochi cooley (1 nymph). ticks collected from a ...201020943027
ticks (acari: ixodidae) infesting wild birds in the atlantic forest in northeastern brazil, with notes on rickettsial infection in ticks.a total of 232 individuals representing 46 species of birds were mist-netted and screened for ticks in a region of the atlantic forest, state of bahia, brazil. thirty-eight (16.4%) of these birds representing 17 species were found infested by immature stages of amblyomma ticks, namely, amblyomma longirostre (koch, 1844) (15 larvae and seven nymphs), amblyomma nodosum (neumann, 1899) (nine nymphs), amblyomma calcaratum (neumann, 1899) (five nymphs), amblyomma cajennense (fabricius, 1787) (seven l ...201020953629
physiological effects upon amblyomma americanum (acari: ixodidae) infected with beauveria bassiana (ascomycota: hypocreales).unfed adult amblyomma americanum were exposed to the entomopathogenic fungus beauveria bassiana. ticks exposed to the fungus exhibited reduced survival and increased water loss as indicated by change in weight. treated ticks survived 7.2 ± 0.22 days (mean ± se) and controls survived 17.9 ± 0.73 days (p = 0.01; df = 57). at death, ticks exposed to the fungus had lost 25.2 ± 0.84% of their starting weight; control ticks had lost 14.1 ± 0.85% of their starting weight (p = 0.01; df = 96). water loss ...201020957415
biological differences between two allopatric populations of amblyomma cajennense (acari: ixodidae) in argentina.the fertility of hybrids from two distinct populations of amblyomma cajennense from different ecological regions of northern argentina was analyzed. two colonies of a. cajennense from el rey national park (rnp), salta province (24º41's, 64º36'w), and copo national park (cnp), santiago del estero province (25º55's, 61º43'w) were established infesting rabbits with adults collected from vegetation. reproductive parameters of the first generation in laboratory of each colony and their crosses were e ...201020972702
monitoring of resistance or susceptibility of adults and larvae of amblyomma cajennense (acari: ixodidae) to synthetic acaricides in goiás, brazil.amblyomma cajennense or the cayenne tick is a three-host ixodid tick species of low parasitic specificity that is the principal vector of brazilian spotted fever. the primary objective of this study was to evaluate the possible development of resistance by adult specimens of a. cajennense to deltamethrin, a synthetic pyrethroid insecticide and the principal miticide/acaricide commercially available in the region. the second objective was to monitor the susceptibility and/or resistance of larvae ...201020976616
absence of rickettsia rickettsii and occurrence of other spotted fever group rickettsiae in ticks from tennessee.rocky mountain spotted fever (rmsf) is the most common tick-borne illness in tennessee. little is known about the occurrence of r. rickettsii, the causative agent, in ticks in tennessee. to better understand the prevalence and distribution of rickettsial agents in ticks, we tested 1,265 amblyomma, dermacentor, and ixodes adult and nymphal ticks. additionally, we tested 231 amblyomma americanum larvae. ticks were collected from 49 counties from humans, wild animals, domestic canines, and flannel ...201020810834
rickettsial infection in domestic mammals and their ectoparasites in el valle de antón, coclé, panamá.the present research evaluated the presence of rickettsia spp. on ectoparasites of horses and dogs (using pcr techniques), and their sera (using immunofluorescence assay) in el valle de antón town in panama. a total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks rhipicephalus sanguineus, amblyomma ovale, amblyomma oblongoguttatum, and the flea ctenocephalides felis), and two tick species on horses (amblyomma cajennense and dermacentor nitens). dna ...201021144663
high prevalence of rickettsia gravesii sp. nov. in amblyomma triguttatum collected from feral pigs.a survey of ectoparasites on feral pigs identified two commonly occurring ixodid tick species; amblyomma triguttatum triguttatum and ixodes australiensis. molecular screening of a. t. triguttatum and i. australiensis for the presence of rickettsia species detected the presence of rickettsiae belonging to the spotted fever group (sfg) in 78.4% of screened a. t. triguttatum. none of the screened i. australiensis were positive for rickettsiae. sequence analysis of the glta and ompa loci of positive ...201020488632
identification of protective antigens by rna interference for control of the lone star tick, amblyomma americanum.the lone star tick, amblyomma americanum, vectors pathogens of emerging diseases of humans and animals in the united states. currently, measures are not available for effective control of a. americanum infestations. development of vaccines directed against tick proteins may reduce tick infestations and the transmission of tick-borne pathogens. however, the limiting step in tick vaccine development has been the identification of tick protective antigens. herein, we report the application of rna i ...201020018267
effects of a lone star tick (amblyomma americanum) burden on performance and metabolic indicators in growing beef steers.we examined the response of selected animal performance, endocrine, immune, and metabolic factors from 13 steers (254+/-6.1 kg) with and without a lone star (amblyomma americanum) tick burden during progressive days of the tick feeding cycle. steers were randomly assigned to either non-treated controls or treated with 300 adult pair of a. americanum per animal. animals were weighed and blood sampled on days -7, 0, 10, 14, 21, 28, and 35 relative to tick treatment. tick treatment did not affect ( ...201020609519
first report of the repellency of 2-tridecanone against ticks.2-tridecanone and 2-undecanone are both found naturally in the trichomes of wild tomato plants and are important in plant resistance to herbivory. 2-undecanone is the u.s. environmental protection agency (epa)-registered active ingredient in the commercially available arthropod repellent, bioud(®) . the goal of this study was to examine the tick repellency of 2-tridecanone. two-choice bioassays were conducted using 8% 2-tridecanone vs. the repellent carrier (absolute ethanol) and compared with t ...201021073492
spread of parasites transported with their hosts: case study of two species of cattle tick.like all parasites, ticks can be spread easily along with their hosts. ticks are obligate parasites of vertebrates, to which they attach themselves for varying periods of time, and are well-adapted to this mode of transport. once the transport stage is complete and they have detached at destination, they are also able to wait several months for the arrival of a new host on which they will continue their life cycle. this leads to the establishment of a secondary tick population. two tropical catt ...201020617654
a new factor xa inhibitor from amblyomma cajennense with a unique domain composition.bioactive compounds of great interest are found in the saliva of hematophagous organisms. while exploring a cdna library derived from the salivary glands of the tick amblyomma cajennense, a transcript that codes for a protein with unique structure (containing an n-terminal kunitz-type domain and a c-terminus with no homology to any annotated sequences) was found. the recombinant mature form of this protein ( approximately 13.5kda) was produced in escherichia coli bl21 (de3), and it was able to i ...201019853573
repellent activity of plant-derived compounds against amblyomma cajennense (acari: ixodidae) nymphs.repellence responses of amblyomma cajennense nymphs to callicarpenal, intermedeol, hyptis suaveolens essential oil, extract of melia azedarach, cymbopogon nardus, spiranthera odoratissima, chenopodium ambrosioides, ageratum conyzoides, mentha pulegium, ruta graveolens, and memora nodosa were studied. among these the extract of c. nardus stood out because of the long-lasting repellence, maintaining, in the highest concentration, 35h of protection against 90% of the nymphs. the essential oil of h. ...201019897309
blood meal analysis to identify reservoir hosts for amblyomma americanum ticks.efforts to identify wildlife reservoirs for tick-borne pathogens are frequently limited by poor understanding of tick-host interactions and potentially transient infectivity of hosts under natural conditions. to identify reservoir hosts for lone star tick (amblyomma americanum)-associated pathogens, we used a novel technology. in field-collected ticks, we used pcr to amplify a portion of the 18s rrna gene in remnant blood meal dna. reverse line blot hybridization with host-specific probes was th ...201020202418
rickettsiae in gulf coast ticks, arkansas, usa.to determine the cause of spotted fever cases in the southern united states, we screened gulf coast ticks (amblyomma maculatum) collected in arkansas for rickettsiae. of the screened ticks, 30% had pcr amplicons consistent with rickettsia parkeri or candidatus rickettsia amblyommii.201020409375
ticks (acari: ixodoidea: argasidae, ixodidae) of china.this paper presents results of an investigation and listing of tick species found in china during a survey in all 28 provinces. this will be a step towards a definitive list of tick species and their distribution. to date, the tick fauna of this area consists of 117 species in the following families: argasidae-argas (7 species), carios (4 species) and ornithodoros (2 species); ixodidae-amblyomma (8 species), anomalohimalaya (2 species), dermacentor (12 species), haemaphysalis (44 species), hyalo ...201020101443
ticks (acari: ixodidae) infesting wild birds in the eastern amazon, northern brazil, with notes on rickettsial infection in ticks.the aim of the study was to report tick infestations on wild birds in a region of the eastern brazilian amazon and evaluate the rickettsial infection of these ticks. wild birds captured by mist nets were examined for the presence of ticks, which were collected and identified to species by morphology or molecular methods. in addition, part of these ticks was individually tested by polymerase chain reaction targeting portions of the rickettsial genes glta and ompa. among 331 captured birds, repres ...201020140452
exploiting the heterogeneous drop-off rhythm of amblyomma variegatum nymphs to reduce pasture infestation by adult ticks.tick distribution depends on the drop-off rhythm of the previous stage and on the suitability for tick survival of the environment where they are disseminated. studies were implemented in burkina faso to assess detachment pattern of engorged amblyomma variegatum nymphs. experiments were carried out with naturally infested cattle kept in a paddock or monitored when grazing community pasture. in the pasture, 80% of the nymphs detached between 14.00 h and 17.00 h while less than 25% did so in the p ...201020441678
elemol and amyris oil repel the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.the essential oil from amyris balsamifera (rutaceae) and elemol, a principal constituent of the essential oil of osage orange, maclura pomifera (moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, ixodes scapularis, and the lone star tick, amblyomma americanum. both bioassays took advantage of the tendency of these host-seeking ticks to climb slender vertical surfaces. in one bioassay, the central porti ...201020016930
molecular detection of rickettsia amblyommii in amblyomma americanum parasitizing humans.a quantitative real-time polymerase chain reaction assay to detect and quantify a portion of the outer membrane protein b gene (ompb) of rickettsia amblyommii was employed to assess the threat of r. amblyommii exposure to humans parasitized by amblyomma americanum (the lone star tick). a total of 72 pools of lone star ticks removed from humans were acquired from two collections and used in this study: 44 pools of a. americanum submitted to the department of defense human tick test kit program in ...201019877809
dissemination of spotted fever rickettsia agents in europe by migrating birds.migratory birds are known to play a role as long-distance vectors for many microorganisms. to investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in sweden. a total of 1127 ixodes spp. ticks were removed from these birds and the extracted dna from 957 of them was available for analyses. the dna was assayed for detection of rickettsia spp. using real-time pcr, followed by dna sequencing for spec ...201020052286
severe ehrlichia infection in pediatric oncology and stem cell transplant patients.ehrlichiosis, a tickborne illness transmitted by tick vectors amblyomma americanum and ixodes scapularis, can be acquired in endemic areas. clinical manifestations range from asymptomatic to fulminant in nature. we report three cases of ehrlichiosis in pediatric oncology patients, one of whom was a stem cell transplant recipient. early symptoms included fever, malaise, and vague gastrointestinal symptoms. laboratory abnormalities were initially attributed to chemotherapy toxicity. illness was se ...201020052776
performance of a metarhizium anisopliae-treated semiochemical-baited trap in reducing amblyomma variegatum populations in the field.experiments were carried out to evaluate the efficacy of metarhizium anisopliae (metsch.) sorok. (ascomycota: hypocreales)-treated semiochemical-baited traps for control of amblyomma variegatum fabriscius (acari: ixodidae) under field conditions. unfed a. variegatum adults (118) were seeded in each 100-m plot and allowed to acclimatise for 3 days. on the fourth day (day 4), an emulsifiable formulation of m. anisopliae (consisting of 49.5% sterile distilled water, fungal conidia, 49.5% corn oil a ...201020153931
bacterial diversity in amblyomma americanum (acari: ixodidae) with a focus on members of the genus rickettsia.the lone star tick, amblyomma americanum (acari: ixodidae), is commonly reported from people and animals throughout the eastern u.s. and is associated with transmission of a number of emerging diseases. to better define the microbial communities within lone star ticks, 16s rrna gene based analysis using bacteria-wide primers, followed by sequencing of individual clones (n = 449) was used to identify the most common bacterial operational taxonomic units (otus) present within colony-reared and wil ...201020380308
repellent activity of deet against amblyomma cajennense (acari: ixodidae) nymphs submitted to different laboratory bioassays.this study was developed to evaluate the repellent activity of n,n-diethyl-3-methylbenzamide (deet) against amblyomma cajennense nymphs. two repellent bioassays were compared and the effective concentration and repellent time were calculated. the fingertip test was accomplished to evaluate in vivo four concentrations of the compound (0.200; 0.100; 0.050 and 0.025 mg.cm⁻²) and the filter-paper bioassay to evaluate in vitro the two highest concentrations.the compound provided repellence higher tha ...201020385054
natural history of ehrlichia chaffeensis: vertebrate hosts and tick vectors from the united states and evidence for endemic transmission in other countries.ehrlichia chaffeensis, an intracellular gram-negative zoonotic bacterium, is the causative agent of human monocytotropic ehrlichiosis (hme). in humans, the disease can range from a mild, non-specific illness with few to no clinical signs to a moderately severe to fatal disease, especially those with compromised immune systems. e. chaffeensis is maintained in a complex cycle involving white-tailed deer (wtd; odocoileus virginianus) as a primary reservoir and the lone star tick (lst; amblyomma ame ...201019819631
the life cycle of amblyomma auricularium (acari: ixodidae) using rabbits (oryctolagus cuniculus) as experimental host.the life cycle of amblyomma auricularium (conil) is reported for the first time, using rabbits as experimental host. developmental periods of free-living stages were observed in an incubator at 27 +/- 1 degrees c, 80 +/- 10% rh and 24 h darkness. the complete life cycle, including pre-feeding periods for each parasitic stage, ranged from 97 to 162 days. the overall sex ratio was 1.16:1 (m:f). feeding and premolt periods, molting success, and engorgement weight of nymphs were statistically differ ...201019554463
detection of anaplasma phagocytophilum in amblyomma flavomaculatum ticks (acari: ixodidae) collected from lizard varanus exanthematicus imported to poland.adults and nymphs of amblyomma exornatum, a. flavomaculatum, a. latum, amblyomma spp. and hyalomma aegyptium, were collected from savannah monitors, royal python (africa, ghana) and marginated tortoises (europe, greece) imported to poland, in 2004-2007. altogether 345 ticks were examined by polymerase chain reaction for rickettsial agents. none of the tested ticks was positive for the glta gene of rickettsia spp. dna of 16s rrna gene from anaplasma phagocytophilum was amplified and sequenced fro ...201020084536
hosts, distribution and genetic divergence (16s rdna) of amblyomma dubitatum (acari: ixodidae).we supply information about hosts and distribution of amblyomma dubitatum. in addition, we carry out an analysis of genetic divergence among specimens of a. dubitatum from different localities and with respect to other neotropical amblyomma species, using sequences of 16s rdna gene. although specimens of a. dubitatum were collected on several mammal species as cattle horse, tapirus terrestris, mazama gouazoubira, tayassu pecari, sus scrofa, cerdocyon thous, myocastor coypus, allouata caraya, glo ...201020084537
anti-chemokine activities of ixodid ticks depend on tick species, developmental stage, and duration of feeding.ixodid ticks require comparatively large bloodmeals for their development and survival. blood-feeding elicits signaling events in the host leading to wound healing responses (hemostasis, inflammation, and tissue repair) and immunity. bioactive molecules present in tick saliva sabotage these host responses at several levels. one of them is neutralization of cellular communication by binding of specific saliva molecules to cytokines that have important roles in innate and adaptive immunity. chemok ...201019836889
natural history of ehrlichia ruminantium.ehrlichia ruminantium is an obligately intracellular proteobacterium which causes a disease known as heartwater or cowdriosis in some wild, and all domestic, ruminants. the organism is transmitted by ticks of the genus amblyomma, and it is of serious economic importance wherever the natural vectors occur, an area which includes all of sub-saharan africa, and several islands in the caribbean. the disease was first recognized in south africa in the 19th century, where its tick-borne nature was det ...201019836892
macrophage migration inhibitory factor expression and protein localization in amblyomma americanum (ixodidae).amblyomma americanum (l.) ticks continue to emerge as disease vectors in many areas of the united states. tick macrophage migration inhibitory factor (mif) was first identified in a. americanum females and has been demonstrated to inhibit macrophage movement to the same extent as human mif. this study was conducted to further characterize and elucidate the physiological role for mif in tick feeding. a relative quantitative pcr assay was developed to determine the level of mif gene expression dur ...201019784782
isolation and characterization of a novel borrelia group of tick-borne borreliae from imported reptiles and their associated ticks.the members of the genus borrelia are transmitted by arthropods and known to be infectious to vertebrates. here we found isolates and dnas belonging to the borrelia turcica and unknown borrelia species from imported reptiles and their ectoparasites. the borrelia strains were isolated from blood and multiple organs of exotic tortoises, and were experimentally infectious to captive-bred tortoises. these findings suggest that these tortoises may be a candidate as the reservoir host of the borrelia ...201019758349
prevalence of ehrlichia chaffeensis and ehrlichia ewingii in ticks from tennessee.human ehrlichiosis is the second most common tick-borne disease reported in tennessee after rocky mountain spotted fever. two closely related ehrlichiae, ehrlichia chaffeensis and ehrlichia ewingii, are both causative agents of human disease and are transmitted by amblyomma americanum, the lone star tick. prevalence rates and distribution patterns of these pathogens among ticks in tennessee are currently unknown. to understand prevalence and exposure risk of ehrlichia spp., we tested 616 ticks ( ...201019877819
analysis of amblyomma surveillance data in the caribbean: lessons for future control programmes.amblyomma variegatum, the tropical bont tick (tbt), is the principal vector of heartwater and is associated with dermatophilosis, major causes of losses in animal production and mortality in caribbean livestock. from 1995 to 2007, the caribbean amblyomma programme (cap) supported treatment and surveillance activities in 11 islands of the eastern caribbean with an initial objective of eradicating tbt. in addition to control activities, surveillance data were collected between 1997 and 2006 in a u ...201019833441
cattle and the natural history of rickettsia parkeri in mississippi.abstract cattle have been recognized as hosts for amblyomma maculatum, the gulf coast tick, for over 100 years. for nearly as long, a. maculatum have been known to harbor the spotted fever group rickettsia (sfgr), now known as rickettsia parkeri. however, human infection with r. parkeri was not documented until 2004. results presented herein describe a laboratory and a field study evaluating cattle and the natural history of a. maculatum and r. parkeri in mississippi. in the laboratory study, se ...201120846012
tick surveillance in great britain.the ability for public/veterinary health agencies to assess the risks posed by tick-borne pathogens is reliant on an understanding of the main tick vector species. crucially, the status, distribution, and changing trends in tick distribution and abundance are implicit requirements of any risk assessment; however, this is contingent on the quality of tick distribution data. since 2005 the health protection agency has promoted an enhanced tick surveillance program. through engagement with a variet ...201120849277
emergence of rickettsia africae, oceania.we detected rickettsia africae, the agent of african tick-bite fever (atbf), by amplification of fragments of glta, ompa, and ompb genes from 3 specimens of amblyomma loculosum ticks collected from humans and birds in new caledonia. clinicians who treat persons in this region should be on alert for atbf.201121192865
ecology and dynamics of the blood parasite, hepatozoon tuatarae (apicomplexa), in tuatara (sphenodon punctatus) on stephens island, new zealand.we explored infection patterns and temporal dynamics of the protozoan blood parasite hepatozoon tuatarae (apicomplexa) infecting the tuatara (sphenodon punctatus), a protected reptile living on stephens island, new zealand. in march 2006, we surveyed tuatara in five study sites to examine spatial variation in infection prevalence, and four times, from may 2005 to november 2006, we recaptured marked individuals within three study sites to examine the temporal dynamics of infection. we also examin ...201121270002
experimental infection of amblyomma aureolatum ticks with rickettsia rickettsii.we experimentally infected amblyomma aureolatum ticks with the bacterium rickettsia rickettsii, the etiologic agent of rocky mountain spotted fever (rmsf). these ticks are a vector for rmsf in brazil. r. rickettsii was efficiently conserved by both transstadial maintenance and vertical (transovarial) transmission to 100% of the ticks through 4 laboratory generations. however, lower reproductive performance and survival of infected females was attributed to r. rickettsii infection. therefore, bec ...201121529391
rickettsia rickettsii transmission by a lone star tick, north carolina.only indirect or circumstantial evidence has been published to support transmission of rickettsia rickettsii by amblyomma americanum (lone star) ticks in north america. this study provides molecular evidence that a. americanum ticks can function, although most likely infrequently, as vectors of rocky mountain spotted fever for humans.201121529399
rickettsia parkeri in gulf coast ticks, southeastern virginia, usa.we report evidence that amblyomma maculatum tick populations are well established in southeastern virginia. we found that 43.1% of the adult gulf coast ticks collected in the summer of 2010 carried rickettsia parkeri, suggesting that persons living in or visiting southeastern virginia are at risk for infection with this pathogen.201121529406
amblyomma americanum (l.) (acari: ixodidae) tick salivary gland serine protease inhibitor (serpin) 6 is secreted into tick saliva during tick feeding.in order to successfully feed and transmit disease agents, ticks are thought to inject serine protease inhibitors (serpins) into the host to modulate host defense responses to tick feeding, such as inflammation, the complement activation pathway and blood coagulation. in this study, we show that amblyomma americanum (aam) serpin (s) 6 is putatively injected into the host during tick feeding, in that the antibody to recombinant (r) aams6 specifically reacted with the expected ~43/45 kda aams6 pro ...201121270316
cross-mating experiments with geographically different populations of amblyomma cajennense (acari: ixodidae).the present study evaluated the reproductive compatibility of the crosses between adult ticks of the following three geographically different populations of amblyomma cajennense: state of são paulo (sp), southeastern brazil; state of rondônia (ro), northern brazil; and colombia (co). in addition, crosses between a. cajennense ticks from argentina (ar) and sp ticks were also performed. the argentinean population (ar) was compatible with sp because their crosses resulted in high % egg hatching (me ...201121286933
salivary glands of amblyomma cajennense (acari: ixodidae): a histological and an ultrastructural overview.the present study on the salivary glands of semi-engorged amblyomma cajennense females has identified the various cell types present in this tissue and allowed its morphohistochemical characterization. marking techniques were applied to detect polysaccharides (pas), proteins (bromophenol blue), lipids (nile blue) and calcium (von kossa), as well as those of scanning electron microscopy (sem) and transmission electron microscopy (tem). the results obtained by tem showed and confirmed that these i ...201121301932
first reports of ectoparasites collected from wild-caught exotic reptiles in florida.we collected ectoparasites from 27 of 51 wild-caught, free-ranging exotic reptiles examined in florida from 2003 to 2008. sampled animals represented eight species, five of which yielded ectoparasites. reported new parasite distribution records for the united states include the following: the first collection of the african tick amblyomma latum (koch) from a wild-caught animal [ball python, python regius (shaw)] in the united states; the first collection of the lizard scale mite hirstiella stami ...201121337954
beauveria bassiana (ascomycota: hypocreales) as a management agent for free-living amblyomma americanum (acari: ixodidae) in ohio.unfed adult amblyomma americanum were exposed to the entomopathogenic fungus beauveria bassiana and placed in the field. ticks exposed to the fungus experienced higher mortality than those in the control group (p = 0.001). it is recommended that for inclusion in a tick management program, the fungus be applied in the late evening during the months march through june as this is when ticks are most active and conditions suitable for fungal activity occur.201120607363
antigen-presenting cells in draining lymph nodes of goats repeatedly infested by the cayenne tick amblyomma cajennense nymphs.resistance to tick feeding has been previously shown to be an acquired, immunologically mediated phenomenon in goats, associated with cutaneous basophilia to nymphs of amblyomma cajennense, the cayenne tick, after repeated infestations. on the other hand, it is well known that antigen-presenting cells (apcs) play an important role in the host immune reaction to tick infestations. the most able apcs for th cells are the well defined dendritic cells, mononuclear phagocytes and b-lymphocytes. immun ...201120596885
conjunctival attachment of a tick: clinicopathologic report of a case.attachment by ticks to ocular surfaces is uncommon, but has been reported. the objective of this article is to describe a case of conjunctival tick attachment and a method for removal by conjunctival excision. a 39-year-old man presented to the emergency department with a complaint of foreign-body sensation in his right eye. he was found to have a live tick embedded in his conjunctiva. the tick was removed en bloc with surrounding conjunctiva by an ophthalmologist. the arthropod was identified a ...201118514466
comparative analysis of hemocyte phagocytosis between six species of arthropods as measured by flow cytometry.phagocytosis of pathogens by hemocytes is a rapid-acting immune response and represents a primary means of limiting microbial infection in some species of arthropods. to survey the relative capacity of hemocyte phagocytosis as a function of the arthropod immune response, we examined the extent of phagocytosis among a wide taxonomic range of arthropod species including a decapod crustacean (litopenaeus vannamei), three ixodid tick species (amblyomma americanum, dermacentor variabilis, and ixodes ...201121843526
plant extracts, isolated phytochemicals, and plant-derived agents which are lethal to arthropod vectors of human tropical diseases--a review.the recent scientific literature on plant-derived agents with potential or effective use in the control of the arthropod vectors of human tropical diseases is reviewed. arthropod-borne tropical diseases include: amebiasis, chagas disease (american trypanosomiasis), cholera, cryptosporidiosis, dengue (hemorrhagic fever), epidemic typhus (brill-zinsser disease), filariasis (elephantiasis), giardia (giardiasis), human african trypanosomiasis (sleeping sickness), isosporiasis, leishmaniasis, lyme di ...201121432748
case of tick bite with infestation of an extraordinary number of larval amblyomma testudinarium ticks. 201121434986
the relevance of tick bites to the production of ige antibodies to the mammalian oligosaccharide galactose-a-1,3-galactose.in 2009, we reported a novel form of delayed anaphylaxis to red meat that is related to serum ige antibodies to the oligosaccharide galactose-a-1,3-galactose (alpha-gal). most of these patients had tolerated meat for many years previously. the implication is that some exposure in adult life had stimulated the production of these ige antibodies.201121453959
risk factors for african tick-bite fever in rural central africa.african tick-bite fever is an emerging infectious disease caused by the spotted fever group rickettsia, rickettsia africae, and is transmitted by ticks of the genus amblyomma. to determine the seroprevalence of exposure to r. africae and risk factors associated with infection, we conducted a cross-sectional study of persons in seven rural villages in distinct ecological habitats of cameroon. we examined 903 plasma samples by using an indirect immunofluorescence assay for antibodies to r. africae ...201121460018
susceptibility of four tick species, amblyomma americanum, dermacentor variabilis, ixodes scapularis, and rhipicephalus sanguineus (acari: ixodidae), to nootkatone from essential oil of grapefruit.toxicity of nootkatone was determined in laboratory assays against unfed nymphs of amblyomma americanum l., dermacentor variabilis (say), ixodes scapularis say, and rhipicephalus sanguineus latreille. we determined the 50% lethal concentration (lc50) and 90% lethal concentration (lc90) of nootkatone by recording tick mortality 24 h after exposure in treated glass vials. nymphs were susceptible to nootkatone with lc50 values of 0.352, 0.233, 0.169, and 0.197 microg/cm2, and lc90 values of 1.001, ...201121485368
life cycle of the tick amblyomma parvum aragão, 1908 (acari: ixodidae) and suitability of domestic hosts under laboratory conditions.amblyomma parvum is a widespread neotropical tick found on several domestic animals and is known to harbor a rickettsia species of yet unknown pathogenicity. however its life cycle on, and suitability of, several of these hosts has not been described. in this work the biology of a. parvum is presented when fed on seven domestic hosts (chicken, dog, rabbit, horse, guinea pig, cattle and goat). the complete life cycle of the tick varied from 96.8 to 102 days. highest engorgement weight of larvae w ...201121353392
the action of amblyomma cajennense tick saliva in compounds of the hemostatic system and cytotoxicity in tumor cell lines.ticks are blood-feeding arthropods that secrete anticoagulant molecules to maintain the fluidity of the blood during its feeding. tick saliva has many compounds with biological activities that interact directly with host systems, such as blood clotting, platelet aggregation, cell death, among others. some reports show that there are proteins with anticancer properties in tick saliva. this paper reports some of the biological roles of the amblyomma cajennense tick saliva, including factor xa and ...201121723081
Effect of Forest Fragmentation on Tick Infestations of Birds and Tick Infection Rates by Rickettsia in the Atlantic Forest of Brazil.Habitat loss and modifications affect biodiversity, potentially contributing to outbreaks of infectious diseases. We evaluated if the patch sizeinfragmented areas of Atlantic Forest in southeastern Brazil influences the diversity of forest birds and consequently the prevalence of ticks on birds and the rickettsial infection of these ticks. During 2 years, we collected ticks from birds in 12 sites: four small forest patches (80-140 ha), four large ones (480-1,850 ha), and four forest control area ...201122173291
Development of multiple-locus variable-number tandem-repeat analysis for rapid genotyping of Ehrlichia ruminantium and its application to infected Amblyomma variegatum collected in heartwater endemic areas in Uganda.SUMMARYThe rickettsial bacterium Ehrlichia ruminantium is the causative agent of heartwater, a serious tick-borne disease in ruminants. The genetic diversity of organisms in the field will have implications for cross-protective capacities of any vaccine developed, and for an effective vaccine design strategy proper genotyping and understanding of existing genetic diversity in the field is necessary. We searched for variable-number tandem-repeat (VNTR) loci for use in a multi-locus VNTR analysis ...201122008706
Coxiella burnetii in Western Barred Bandicoots (Perameles bougainville) from Bernier and Dorre Islands in Western Australia.The aim of this work is to investigate the presence of Coxiella burnetii in Perameles bougainville and their ticks on two islands off Western Australia. Haemaphysalis humerosa, Haemaphysalis ratti, and Haemaphysalis lagostrophi were collected from P. bougainville on Bernier and Dorre Islands from 2005 to 2007; only Amblyomma limbatum was collected from humans over the same interval. One of 13 tick samples and 1 of 12 P. bougainville fecal samples were positive for C. burnetii DNA using quantitat ...201122167449
Detection of Rickettsia parkeri and Candidatus Rickettsia andeanae in Amblyomma maculatum Gulf Coast Ticks Collected from Humans in the United States.Abstract Rickettsia parkeri, a spotted fever group (SFG) rickettsia recently found to be pathogenic to humans, causes an eschar-associated febrile illness. The R. parkeri rickettsiosis, Tidewater spotted fever, has been misdiagnosed as Rocky Mountain spotted fever due to serologic cross reactivity and the lack of specific diagnostic methods. Candidatus Rickettsia andeanae, also a SFG rickettsia, is a recently described agent of unknown pathogenicity originally identified in ticks collected fro ...201122022815
essential oils of cupressus funebris, juniperus communis, and j. chinensis (cupressaceae) as repellents against ticks (acari: ixodidae) and mosquitoes (diptera: culicidae) and as toxicants against mosquitoes.juniperus communis leaf oil, j. chinensis wood oil, and cupressus funebris wood oil (cupressaceae) from china were analyzed by gas chromatography and gas chromatography-mass spectrometry. we identified 104 compounds, representing 66.8-95.5% of the oils. the major components were: α-pinene (27.0%), α-terpinene (14.0%), and linalool (10.9%) for j. communis; cuparene (11.3%) and δ-cadinene (7.8%) for j. chinensis; and α-cedrene (16.9%), cedrol (7.6%), and β-cedrene (5.7%) for c. funebris. the essen ...201122129397
relationships between tick counts and coat characteristics in nguni and bonsmara cattle reared on semiarid rangelands in south africa.indigenous nguni cattle are adapted to the semiarid rangeland and appear to be resistant to ticks; however, the mechanism for tick resistance is yet to be established. to understand tick resistance in cattle, relationships among skin thickness, hair length, coat score, and tick counts were estimated in nguni (n=12) and bonsmara (n=12) heifers on semiarid rangelands of south africa. the tick species observed to infest the heifers were rhipicephalus (boophilus) decoloratus (frequency: 76%), rhipic ...201121890073
tick cell lines for study of crimean-congo hemorrhagic fever virus and other arboviruses.abstract continuous cell lines derived from many of the vectors of tick-borne arboviruses of medical and veterinary importance are now available. their role as tools in arbovirus research to date is reviewed and their potential application in studies of tick cell responses to virus infection is explored, by comparison with recent progress in understanding mosquito immunity to arbovirus infection. a preliminary study of propagation of the human pathogen crimean-congo hemorrhagic fever virus (cc ...201121955214
acaricidal effect of an isolate from hoslundia opposita vahl against amblyomma variegatum (acari: ixodidae).hoslundia opposita vahl. (lamiaceae), a common local shrub in ghana, is traditionally known not only for its pharmacological benefits but also for its insecticidal properties. its acaricidal property, however, has not been investigated.201122022167
induction of complete courtship ritual in amblyomma cajennense using 2,6-dichlorophenol at female-equivalent quantities.in order to clarify the role of 2,6-dichlorophenol (2,6-dcp) in the courtship of amblyomma cajennense, sexually mature males that had previously fed on rabbits were tested in bioassays. the males were released onto dummies treated with whole female extract or synthetic 2,6-dcp at a concentration of two female equivalents, or with hexane (control), and their responses were observed. in the presence of both the extract and 2,6-dcp, excitation was observed among the males, expressed in the form of ...201122166393
factors associated to theileria equi in equids of two microregions from rio de janeiro, brazil.serum samples from 714 equids of itaguaí and serrana microregions, rio de janeiro, southeastern brazil, were examined by indirect fluorescent antibody test (titer 1:80) for theileria equi. the prevalence in the microregions and factors associated with seropositivity were evaluated and the prevalence ratio (pr) calculated. the overall prevalence of t. equi infection was 81.09% (n = 579), with higher prevalence (p < 0.05) in the itaguaí (85.43%) when compared to serrana microregion (76.92%). the g ...201121961755
Ehrlichia chaffeensis transcriptome in mammalian and arthropod hosts reveals differential gene expression and post transcriptional regulation.Human monocytotropic ehrlichiosis is an emerging life-threatening zoonosis caused by obligately intracellular bacterium, Ehrlichia chaffeensis. E. chaffeensis is transmitted by the lone star tick, Amblyomma americanum, and replicates in mononuclear phagocytes in mammalian hosts. Differences in the E. chaffeensis transcriptome in mammalian and arthropod hosts are unknown. Thus, we determined host-specific E. chaffeensis gene expression in human monocyte (THP-1) and in Amblyomma and Ixodes tick ce ...201121915290
structure of thymidylate kinase from ehrlichia chaffeensis.the enzyme thymidylate kinase phosphorylates the substrate thymidine 5'-phosphate (dtmp) to form thymidine 5'-diphosphate (dtdp), which is further phosphorylated to dttp for incorporation into dna. ehrlichia chaffeensis is the etiologic agent of human monocytotropic erlichiosis (hme), a potentially life-threatening tick-borne infection. hme is endemic in the united states from the southern states up to the eastern seaboard. hme is transmitted to humans via the lone star tick amblyomma americanum ...201121904055
a novel rickettsia infecting amblyomma dubitatum ticks in brazil.a total of 130 adult free-living ticks of amblyomma cajennense and 9 free-living amblyomma dubitatum were collected in the surroundings of the pampulha lake, within belo horizonte city, state of minas gerais, south-eastern brazil. each adult tick was tested for rickettsial infection by pcr protocols targeting the rickettsial genes glta, htra, and ompa. all the 130 a. cajennense ticks were negative by pcr. in contrast, all 9 a. dubitatum ticks were shown to contain rickettsial dna. pcr products w ...201122108014
A new typing technique for the Rickettsiales Ehrlichia ruminantium: Multiple-locus variable number tandem repeat analysis.Ehrlichia ruminantium (ER) is a member of the order Rickettsiales transmitted by Amblyomma ticks. This obligatory intracellular bacterium is the causative agent of a fatal disease in ruminants, named heartwater. It represents a constraint on breeding development in sub-Saharan Africa and in the Caribbean. The genetic diversity of the strains of ER, which could be a limiting factor to obtain effective vaccines, needs to be better characterized. For this purpose, we developed a molecular typing te ...201122143037
in vitro propagation of candidatus rickettsia andeanae isolated from amblyomma maculatum.candidatus rickettsia andeanae was identified during an investigation of a febrile outbreak in northwestern peru (2002). dna sequencing from two ticks (amblyomma maculatum, ixodes boliviensis) collected during the investigation revealed a novel rickettsia agent with similarity to the spotted fever group rickettsiae. since then, candidatus r. andeanae has been detected in a. maculatum ticks collected in the southeastern and southcentral united states, argentina, and peru. to date, candidatus r. a ...201122098316
[surveillance of rickettsia sp. infection in capybaras (hydrochoerus hydrochaeris) a potential model of epidemiological alert in endemic areas].introduction. capybaras (hydrochoerus hydrochaeris) are considered amplifying hosts of rickettsia sp. these rodents are usually parasitized by the tick vector, amblyomma cajennense, the main vector of rickettsioses in humans and animals in south america. capybaras can be used as sentinels in detection of circulation of rickettsiae. objective. antibodies to rickettsiae of spotted fever group were detected in capybaras in a rural area of cordoba province, northern colombia. materials and methods. ...201122159538
Southern Tick-Associated Rash Illness (STARI) in the North: STARI following a tick bite in Long Island, New York.The most common clinical manifestation of Lyme disease is the characteristic rash, erythema migrans (EM). In the 1980s EM-like eruptions were reported in Missouri and other southeastern states. The EM-like eruptions, which were of unknown etiology, often followed the bite of the Lone Star tick (Amblyomma americanum) and the rash is called STARI (southern tick-associated rash illness). Although the Lone Star tick is found in the Lyme disease-endemic areas of New England and Mid-Atlantic regions o ...201121940418
Seroprevalence and risk factors to Ehrlichia spp. and Rickettsia spp. in dogs from the Pantanal Region of Mato Grosso State, Brazil.Sera of 320 dogs from urban and rural areas of a Pantanal region of Brazil were evaluated for rickettsial (Rickettsia rickettsii, R. parkeri, R. amblyommii, R. rhipicephali, R. felis, and R. bellii) and ehrlichial (Ehrlichia canis) infection by the immunofluorescence assay (IFA). Risk factors for ehrlichiosis or rickettsiosis were also evaluated. Positive reaction against Ehrlichia spp. was detected in 227 (70.9%) dogs, 119 (74.3%) from an urban area and 108 (67.5%) from rural areas (P>0.05). Fo ...201122108015
amblyomma dissimile koch (acari: ixodidae) attacking primolius maracana vieillot (psittaciformes: psittacidae) in the amazon region, state of pará, brazil.the tick amblyomma dissimile koch feeds preferentially on reptiles (squamata), although amphibians (anura) also seem to be important hosts. we report an a. dissimile nymph infesting a blue-winged macaw, primolius maracana, held in captivity in the mangal das garças park, state of pará, brazil. environmental observations suggest that free-living iguanas (iguana iguana), which used to walk on the bird enclosure in the park, were the source of the a. dissimile tick that infested the blue-winged mac ...201121952971
high rates of rickettsia parkeri infection in gulf coast ticks (amblyomma maculatum) and identification of "candidatus rickettsia andeanae" from fairfax county, virginia.the gulf coast tick, amblyomma maculatum, is a vector of rickettsia parkeri, a recently identified human pathogen that causes a disease with clinical symptoms that resemble a mild form of rocky mountain spotted fever. because the prevalence of r. parkeri infection in geographically distinct populations of a. maculatum is not fully understood, a. maculatum specimens collected as part of a tick and pathogen surveillance system in fairfax county, virginia, were screened to determine pathogen infect ...201121867421
equine piroplasmosis associated with amblyomma cajennense ticks, texas, usa.we report an outbreak of equine piroplasmosis in southern texas, usa, in 2009. infection prevalence reached 100% in some areas (292 infected horses). amblyomma cajennense was the predominant tick and experimentally transmitted theileria equi to an uninfected horse. we suggest that transmission by this tick species played a role in this outbreak.201122000367
rickettsia parkeri in amblyomma maculatum ticks, north carolina, usa, 2009-2010.we detected rickettsia parkeri in 20%-33% of amblyomma maculatum ticks sampled in north carolina. results highlight the high frequencies of r. parkeri-infected ticks in the state with the highest annual incidence of rocky mountain spotted fever. epidemiologic studies are needed to definitively link r. parkeri to cases of spotted fever rickettsiosis.201122172164
Study of infection by Rickettsiae of the spotted fever group in humans and ticks in an urban park located in the City of Londrina, State of Paraná, Brazil.Spotted fevers are emerging zoonoses caused by Rickettsia species in the spotted fever group (SFG). Rickettsia rickettsii is the main etiologic agent of Brazilian spotted fever (BSF)and it is transmitted by Amblyomma spp. ticks.201121901874
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