crystal structure and functional characterization of an immunomodulatory salivary cystatin from the soft tick ornithodoros moubata.the saliva of blood-feeding parasites is a rich source of peptidase inhibitors that help to overcome the host's defence during host-parasite interactions. using proteomic analysis, the cystatin omc2 was demonstrated in the saliva of the soft tick ornithodoros moubata, an important disease vector transmitting african swine fever virus and the spirochaete borrelia duttoni. a structural, biochemical and biological characterization of this peptidase inhibitor was undertaken in the present study. rec ...201020545626
sdetection of vector-borne agents in lone star ticks, amblyomma americanum (acari: ixodidae), from this study, we evaluated amblyomma americanum (lone star tick) in mississippi for the presence of ehrlichia chaffeensis, causative agent of human monocytic ehrlichiosis; ehrlichia ewingii, causative agent of human and canine granulocytic ehrlichiosis; borrelia lonestari, putative agent of southern tick-associated rash illness; francisella tularensis, the agent of tularemia; and rickettsia spp., particularly r. amblyommii, a suspected pathogen. we collected adult a. americanum from four region ...201020496596
potential of medicinal plants in mosquito control.medicinal plants have long history as important components in traditional medicine, and food of humans since ancient egyptians and chinese. naturally occurring botanical compounds contain a broad range of chemical active ingredients can intervene in all biological processes of the mosquito, thus interrupt its life cycle and dispersal and reduce harms to humans and animals. many medicinal plants were tested for their pesticide and repellent potential, as crude material, essential oils or individu ...201020503582
ehrlichia ewingii infection and exposure rates in dogs from the southcentral united states.we used pcr and a novel serologic assay to determine infection and exposure rates to ehrlichia ewingii in dogs from an area of northeast oklahoma and northwest arkansas where amblyomma americanum ticks are abundant. of 143 dogs assayed, 13 (9.1%) harbored e. ewingii by pcr and 64 (44.8%) had antibodies to e. ewingii detected using a peptide-based microtiter plate elisa. dogs were more likely (p=0.001) to be positive by pcr if sampled in august (30.8%) but no association was found between seropos ...201020541322
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
quantum of infection of francisella tularensis tularensis in host-seeking dermacentor variabilis.the american dog tick, dermacentor variabilis, is fundamental to the perpetuation of francisella tularensis tularensis on martha's vineyard, massachusetts, u.s.a. although infected ticks are relatively common on the island, human cases deriving from tick bite are rare. it may be that the quantum of bacteria within these naturally infected ticks is frequently too small to cause disease. accordingly, we quantified the amount of f.t. tularensis bacteria in host-seeking ticks from the island. contra ...201020563231
results from a mathematical model for human monocytic ehrlichiosis. 200920584161
a quantitative comparison of two sample methods for collecting amblyomma americanum and dermacentor variabilis (acari: ixodidae) in studies of tick communities, sampling methodology may influence observed patterns. the objective of this study was to compare two sampling methods, dragging and dry ice baiting, in two habitats to assess abundance of off-host ticks. tick communities were monitored from march to december in a forested and an old-field habitat in northeast missouri. in each habitat, eight drag and eight dry ice bait samples were collected every 2 weeks on a permanent grid. the most common ticks collected were a ...201020585839
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
formulations of deet, picaridin, and ir3535 applied to skin repel nymphs of the lone star tick (acari: ixodidae) for 12 hours.the efficacies of a 20% 1-methyl-propyl-2- (hydroxyethyl)-1-piperidinecarboxylate (picaridin) spray, 20% 3-(n-acetyl-n-butyl)aminopropionic acid ethyl ester (ir3535) spray, 20% picaridin lotion, 10% ir3535 lotion, and 33% n,n-diethyl-3-methylbenzamide (deet) cream in repelling nymphal lone star ticks, amblyomma americanum (l.), were determined at 2-h intervals over 12 h using human subjects. a repellent formulation was applied in a 5-cm-wide band encircling a volunteer's lower leg. for each chal ...201020695288
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
progress and obstacles in vaccine development for the ehrlichioses.ehrlichia are tick-borne obligately intracellular bacteria that cause significant diseases in veterinary natural hosts, including livestock and companion animals, and are now considered important zoonotic pathogens in humans. vaccines are needed for these veterinary and zoonotic human pathogens, but many obstacles exist that have impeded their development. these obstacles include understanding genetic and antigenic variability, influence of the host on the pathogen phenotype and immunogenicity, ...201020822349
comparative microarray analysis of rhipicephalus (boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on bos indicus and bos taurus cattle.rhipicephalus (boophilus) microplus is an obligate blood feeder which is host specific to cattle. existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during the tick - host interaction is poor.201020637126
an insight into the sialotranscriptome of the brown dog tick, rhipicephalus sanguineus.rhipicephalus sanguineus, known as the brown dog tick, is a common ectoparasite of domestic dogs and can be found worldwide. r.sanguineus is recognized as the primary vector of the etiological agent of canine monocytic ehrlichiosis and canine babesiosis. here we present the first description of a r. sanguineus salivary gland transcriptome by the production and analysis of 2,034 expressed sequence tags (est) from two cdna libraries, one consctructed using mrna from dissected salivary glands from ...201020650005
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
efficacy of a doxycycline treatment regimen initiated during three different phases of experimental ehrlichiosis.doxycycline is the treatment of choice for canine monocytic ehrlichiosis (cme), a well-characterized disease and valuable model for tick-borne zoonoses. conflicting reports of clearance of ehrlichia canis after treatment with doxycycline suggested that the disease phase during which treatment is initiated influences outcomes of these treatments. the purpose of this study was to evaluate the efficacy of a 28-day doxycycline regimen for clearance of experimental e. canis infections from dogs treat ...201020921310
detection of lyme disease spirochete, borrelia burgdorferi sensu lato, including three novel genotypes in ticks (acari: ixodidae) collected from songbirds (passeriformes) across canada.lyme disease is reported across canada, but pinpointing the source of infection has been problematic. in this three-year, bird-tick-pathogen study (2004-2006), 366 ticks representing 12 species were collected from 151 songbirds (31 passerine species/subspecies) at 16 locations canada-wide. of the 167 ticks/pools tested, 19 (11.4%) were infected with borrelia burgdorferi sensu lato (s.l.). sequencing of the rrf-rrl intergenic spacer gene revealed four borrelia genotypes: b. burgdorferi sensu stri ...201020618658
invasive honeysuckle eradication reduces tick-borne disease risk by altering host dynamics.despite the ubiquity of invasive organisms and their often deleterious effects on native flora and fauna, the consequences of biological invasions for human health and the ecological mechanisms through which they occur are rarely considered. here we demonstrate that a widespread invasive shrub in north america, amur honeysuckle (lonicera maackii), increases human risk of exposure to ehrlichiosis, an emerging infectious disease caused by bacterial pathogens transmitted by the lone star tick (ambl ...201020937859
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
development of loop-mediated isothermal amplification (lamp) assays for rapid detection of ehrlichia ruminantium.the rickettsial bacterium ehrlichia ruminantium is the causative agent of heartwater, a potential zoonotic disease of ruminants transmitted by ticks of the genus amblyomma. the disease is distributed in nearly all of sub-saharan africa and some islands of the caribbean, from where it threatens the american mainland. this report describes the development of two different loop-mediated isothermal amplification (lamp) assays for sensitive and specific detection of e. ruminantium.201021087521
genomic survey of the ectoparasitic mite varroa destructor, a major pest of the honey bee apis mellifera.the ectoparasitic mite varroa destructor has emerged as the primary pest of domestic honey bees (apis mellifera). here we present an initial survey of the v. destructor genome carried out to advance our understanding of varroa biology and to identify new avenues for mite control. this sequence survey provides immediate resources for molecular and population-genetic analyses of varroa-apis interactions and defines the challenges ahead for a comprehensive varroa genome project.201020973996
rabbit tularemia and hepatic coccidiosis in wild rabbit. 201021122253
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
distribution and prevalence of cytauxzoon felis in bobcats (lynx rufus), the natural reservoir, and other wild felids in thirteen states.cytauxzoon felis, a protozoan parasite of wild and domestic felids, is the causative agent of cytauxzoonosis in domestic and some exotic felids in the united states. the bobcat (lynx rufus) is the natural reservoir for this parasite, but other felids such as florida panthers (puma concolor coryii) and domestic cats may maintain long-term parasitemias and serve as reservoirs. experimentally, two tick species, dermacentor variabilis and amblyomma americanum, have demonstrated the ability to transm ...201021071149
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
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
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
a further insight into the sialome of the tropical bont tick, amblyomma variegatum.ticks--vectors of medical and veterinary importance--are themselves also significant pests. tick salivary proteins are the result of adaptation to blood feeding and contain inhibitors of blood clotting, platelet aggregation, and angiogenesis, as well as vasodilators and immunomodulators. a previous analysis of the sialotranscriptome (from the greek sialo, saliva) of amblyomma variegatum is revisited in light of recent advances in tick sialomes and provides a database to perform a proteomic study ...201121362191
an acarologic survey and amblyomma americanum distribution map with implications for tularemia risk in the united states, tickborne diseases occur focally. missouri represents a major focus of several tickborne diseases that includes spotted fever rickettsiosis, tularemia, and ehrlichiosis. our study sought to determine the potential risk of human exposure to human-biting vector ticks in this area. we collected ticks in 79 sites in southern missouri during june 7-10, 2009, which yielded 1,047 adult and 3,585 nymphal amblyomma americanum, 5 adult amblyomma maculatum, 19 adult dermacentor variab ...201121363979
the afhsc-division of geis operations predictive surveillance program: a multidisciplinary approach for the early detection and response to disease outbreaks.the armed forces health surveillance center, division of global emerging infections surveillance and response system operations (afhsc-geis) initiated a coordinated, multidisciplinary program to link data sets and information derived from eco-climatic remote sensing activities, ecologic niche modeling, arthropod vector, animal disease-host/reservoir, and human disease surveillance for febrile illnesses, into a predictive surveillance program that generates advisories and alerts on emerging infec ...201121388561
amblyomma americanum (l.) (acari: ixodidae) tick salivary gland serine protease inhibitor (serpin) 6 is secreted into tick saliva during tick 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
assessment of bacterial diversity in the cattle tick rhipicephalus (boophilus) microplus through tag-encoded pyrosequencing.ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. the cattle tick, rhipicephalus (boophilus) microplus, hinders livestock production in tropical and subtropical parts of the world where it is endemic. tick microbiomes remain largely unexplored. the objective of this study was to explore the r. microplus microbiome by applying the bacterial 16s tag-encoded flx-titanium amplicon pyrosequencing (btefap) technique to characterize its bacterial ...201121211038
experimental primary and secondary infections of domestic dogs with ehrlichia this study, the infection dynamics of ehrlichia ewingii, causative agent of granulocytotropic ehrlichiosis in dogs and humans, was examined in experimentally infected dogs by using a combination of physical examination, hematologic and biochemical analyses, and molecular and serologic assays. for the experimental trials, blood from an e. ewingii-infected dog was inoculated intravenously into two na+»ve dogs and two dogs with prior experimental exposure to e. ewingii (both were negative for e. ...201121397411
the relevance of tick bites to the production of ige antibodies to the mammalian oligosaccharide galactose-a-1, 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
rna interference in ticks.ticks are obligate hematophagous ectoparasites of wild and domestic animals and humans, and are considered to be second worldwide to mosquitoes as vectors of human diseases(1) and the most important vectors affecting cattle industry worldwide(2). ticks are classified in the subclass acari, order parasitiformes, suborder ixodida and are distributed worldwide from arctic to tropical regions(3). despite efforts to control tick infestations, these ectoparasites remain a serious problem for human and ...201121304465
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
rickettsia rickettsii (rickettsiales: rickettsiaceae) in amblyomma americanum (acari: ixodidae) from kansas.the role of lone star ticks as vectors for rocky mountain spotted fever (rmsf) remains poorly described. we compared the entomological inoculation rates (eirs) for rickettsia spp. for representative sites in missouri and kansas, states that frequently report rmsf each year. host-seeking ticks were collected during 2006 and pooled tick homogenates analyzed by polymerase chain reaction to detect probable r. rickettsii, with confirmation for multiple gene targets performed on individual ticks from ...201121485390
distribution and molecular characterization of wolbachia endosymbionts and filarial nematodes in maryland populations of the lone star tick (amblyomma americanum).the lone star tick amblyomma americanum is host to a wide diversity of endosymbiotic bacteria. we identified a novel wolbachia symbiont infecting a. americanum. multilocus sequence typing phylogenetically placed the endosymbiont in the increasingly diverse f supergroup. we assayed a total of 1031 ticks (119 females, 78 males and 834 nymphs in 89 pools) from 16 maryland populations for infection. infection frequencies in the natural populations were approximately 5% in females and <2% (minimum in ...201121410491
tick-borne encephalitis virus in dogs - is this an issue?abstract: the last review on tick-borne encephalitis (tbe) in dogs was published almost ten years ago. since then, this zoonotic tick-borne arbovirus has been geographically spreading and emerging in many regions in eurasia and continues to do so. dogs become readily infected with tbe virus but they are accidental hosts not capable to further spread the virus. they seroconvert upon infection but they seem to be much more resistant to the clinical disease than humans. apart from their use as sent ...201121489255
efficacy of spinosad against acaricide-resistant and -susceptible rhipicephalus (boophilus) microplus and acaricide-susceptible amblyomma americanum and dermacentor variabilis.various acaricide-resistant strains of rhipicephalus (boophilus) microplus, representative of the major resistance mechanisms found in mexico and brazil, were exposed to spinosad using the food and agriculture organization of the united nations larval packet test and adult immersion test (ait). larvae of all strains tested were found to be susceptible to spinosad. conversely, spinosad did not show toxic activity toward engorged females used in the ait. in vitro tests against larvae, nymphs, and ...201121485374
anointing chemicals and hematophagous arthropods: responses by ticks and mosquitoes to citrus (rutaceae) peel exudates and monoterpene components.some birds and mammals roll on or wipe themselves with the fruits or leaves of citrus spp. or other rutaceae. these anointing behaviors, as with anointing in general, are thought to function in the topical acquisition of chemicals that deter consumers, including hematophagous arthropods. we measured avoidance and other responses by nymphal lone star ticks (amblyomma americanum) and adult female yellow fever mosquitoes (aedes aegypti) to lemon peel exudate and to 24 volatile monoterpenes (racemat ...201121409496
the immunopathology of canine vector-borne diseases.abstract: the canine vector-borne infectious diseases (cvbds) are an emerging problem in veterinary medicine and the zoonotic potential of many of these agents is a significant consideration for human health. the successful diagnosis, treatment and prevention of these infections is dependent upon firm understanding of the underlying immunopathology of the diseases in which there are unique tripartite interactions between the microorganism, the vector and the host immune system. although signific ...201121489234
a snapshot of the ixodes scapularis degradome.parasitic encoded proteases are essential to regulating interactions between parasites and their hosts and thus they represent attractive anti-parasitic druggable and/or vaccine target. we have utilized annotations of ixodes scapularis proteases in gene bank and version 9.3 merops database to compile an index of at least 233 putatively active and 150 putatively inactive protease enzymes that are encoded by the i. scapularis genome. the 233 putatively active protease homologs hereafter referred t ...201121596113
suppression of host-seeking ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs after dual applications of plant-derived acaricides in new jersey.we evaluated the ability of dual applications of natural, plant-derived acaricides to suppress nymphal ixodes scapularis say and amblyomma americanum (l.) (acari: ixodidae) in a lyme disease endemic area of new jersey. an aqueous formulation of 2% nootkatone provided >90% control of i. scapularis through 7 d. control declined to 80.9% at 14 d, and a second application was made that provided >95% control through the remaining 4 wk of the nymphal season. nootkatone provided >90% control of a. amer ...201121510219
coxiella symbionts in the cayenne tick amblyomma cajennense.members of the coxiella genus are intracellular bacteria that can infect a variety of animals including humans. a symbiotic coxiella was recently described in amblyomma americanum ticks in the northern hemisphere with no further investigations of other amblyomma species in other geographic regions. these ixodid ticks represent a group of important vectors for human infectious agents. in the present work, we have demonstrated that symbiotic coxiella (scox) are widespread, occurring in south ameri ...201121611689
differential mortality of dog tick vectors due to infection by diverse francisella tularensis tularensis genotypes.abstract the factors involved in the long-term perpetuation of francisella tularensis tularensis in nature are poorly understood. martha's vineyard, massachusetts, has become a site of sustained transmission of type a tularemia, with nearly 100 human cases reported from 2000 to 2010. we have identified a stable focus of f. tularensis transmission there, where the annual prevalence in host-seeking dermacentor variabilis is about 3%, suggesting that this tick perpetuates the agent. however, labora ...201121612530
isolation and characterization of ehrlichia chaffeensis rna polymerase and its use in evaluating p28 outer membrane protein gene promoters.abstract:201121513529
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
basophils, ige, and autoantibody-mediated kidney disease.basophils are of interest in immunology due to their ability to produce a th2-signature cytokine, il-4, following activation. a new understanding of the role of basophils in immunity shows novel functions at a cellular level through which basophils influence adaptive immunity. this review summarizes new advances in basophil biology and discusses new roles for basophils in human disease, especially in the mediation of the pathogenesis of lupus nephritis. recently, basophils have been shown to con ...201121597041
generation, analysis and functional annotation of expressed sequence tags from the ectoparasitic mite psoroptes ovis.abstract: background: sheep scab is caused by psoroptes ovis and is arguably the most important ectoparasitic disease affecting sheep in the uk. the disease is highly contagious and causes and considerable pruritis and irritation and is therefore a major welfare concern. current methods of treatment are unsustainable and in order to elucidate novel methods of disease control a more comprehensive understanding of the parasite is required. to date, no full genomic dna sequence or large scale trans ...201121781297
francisella tularensis molecular typing using differential insertion sequence amplification (disa).tularemia is a potentially fatal disease that is caused by the highly infectious and zoonotic pathogen francisella tularensis. despite the monomorphic nature of sequenced f. tularensis genomes, there is a significant degree of plasticity in the organization of genetic elements. the observed variability in these genomes is primarily due to the transposition of direct repeats and insertion sequence (is) elements. since current methods used to genotype f. tularensis are time-consuming and require e ...201121613430
efficacy of dry ice-baited traps for sampling amblyomma americanum (acari: ixodidae) varies with life stage but not habitat.the carbon dioxide-baited trap is the most common and effective method for sampling vector life-stage amblyomma americanum (l.) (acari: ixodidae), although confounding environmental variables are rarely considered. a mark-recapture experiment was designed to compare recapture proportions of a. americanum nymphs and adults between two habitat types: old field and oak-hickory forest. powdered fluorescent dye was used to mark a. americanum ticks released in 1-m increments from carbon dioxide-baited ...201121661336
emergence of a new pathogenic ehrlichia species, wisconsin and minnesota, 2009.ehrlichiosis is a clinically important, emerging zoonosis. only ehrlichia chaffeensis and e. ewingii have been thought to cause ehrlichiosis in humans in the united states. patients with suspected ehrlichiosis routinely undergo testing to ensure proper diagnosis and to ascertain the cause.201121812671
efficacy of a novel topical combination of fipronil, amitraz and (s)-methoprene for treatment and control of induced infestations with four north american tick species (dermacentor variabilis, ixodes scapularis, amblyomma americanum and amblyomma maculatum) on dogs.five laboratory studies were conducted to confirm that a single topical dose of the novel combination of fipronil, amitraz and (s)-methoprene, certifect™ (merial limited, ga, usa), is efficacious for the rapid control of pre-existing infestations and the prevention of new infestations with ixodes scapularis, dermacentor variabilis, amblyomma americanum and amblyomma maculatum for at least 28 days on dogs. in each study, 8 male and 8 female purpose-bred, laboratory beagles were randomly assigned ...201121777734
the complexity of rhipicephalus (boophilus) microplus genome characterised through detailed analysis of two bac clones.abstract: background: rhipicephalus (boophilus) microplus (rmi) a major cattle ectoparasite and tick borne disease vector, impacts on animal welfare and industry productivity. in arthropod research there is an absence of a complete chelicerate genome, which includes ticks, mites, spiders, scorpions and crustaceans. model arthropod genomes such as drosophila and anopheles are too taxonomically distant for a reference in tick genomic sequence analysis. this study focuses on the de-novo assembly of ...201121777481
toward an understanding of the perpetuation of the agent of tularemia.the epidemiology of tularemia has influenced, perhaps incorrectly skewed, our views on the ecology of the agent of tularemia. in particular, the central role of lagomorphs needs to be reexamined. diverse observations, some incidental, and some that are more generally reproducible, have not been synthesized so that the critical elements of the perpetuation of francisella tularensis can be identified. developing a quantitative model of the basic reproduction number of f. tularensis may require sep ...201121687803
increasing incidence of ehrlichia chaffeensis and anaplasma phagocytophilum in the united states, 2000-2007.ehrlichia chaffeensis causes human monocytic ehrlichiosis, and anaplasma phagocytophilum causes human granulocytic anaplasmosis. these related tick-borne rickettsial organisms can cause severe and fatal illness. during 2000-2007, the reported incidence rate of e. chaffeensis increased from 0.80 to 3.0 cases/million persons/year. the case-fatality rate was 1.9%, and the hospitalization rate was 49%. during 2000-2007, the reported incidence of a. phagocytophilum increased from 1.4 to 3.0 cases/mil ...201121734137
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
Geographical distribution and prevalence of selected Borrelia, Ehrlichia, and Rickettsia infections in Amblyomma americanum (Acari: Ixodidae) in New Jersey.We used published accounts to describe the known statewide distribution of the lone star tick, Amblyomma americanum, in New Jersey and field surveys to characterize the geographical range of A. americanum and selected A. americanum-transmitted pathogens in Monmouth County, the hypothesized northern limit of the species distribution. Ticks were collected using standardized methods from 50 widely dispersed public access areas within 18 municipalities to produce estimates of relative abundance amon ...201122017087
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
mechanisms of obligatory intracellular infection with anaplasma phagocytophilum.anaplasma phagocytophilum persists in nature by cycling between mammals and ticks. human infection by the bite of an infected tick leads to a potentially fatal emerging disease called human granulocytic anaplasmosis. a. phagocytophilum is an obligatory intracellular bacterium that replicates inside mammalian granulocytes and the salivary gland and midgut cells of ticks. a. phagocytophilum evolved the remarkable ability to hijack the regulatory system of host cells. a. phagocytophilum alters vesi ...201121734244
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
An insight into the sialotranscriptome and proteome of the coarse bontlegged tick, Hyalomma marginatum rufipes.Ticks are mites specialized in acquiring blood from vertebrates as their sole source of food and are important disease vectors to humans and animals. Among the specializations required for this peculiar diet, ticks evolved a sophisticated salivary potion that can disarm their host's hemostasis, inflammation, and immune reactions. Previous transcriptome analysis of tick salivary proteins has revealed many new protein families indicative of fast evolution, possibly due to host immune pressure. The ...201121851864
updates on borrelia burgdorferi sensu lato complex with respect to public health.borrelia burgdorferi sensu lato (s.l.) complex is a diverse group of worldwide distributed bacteria that includes 18 named spirochete species and a still not named group proposed as genomospecies 2. descriptions of new species and variants continue to be recognized, so the current number of described species is probably not final. most of known spirochete species are considered to have a limited distribution. eleven species from the b. burgdorferi s.l. complex were identified in and strictly ass ...201121890064
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
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
The indoor air and asthma: the role of cat allergens.The objective is to discuss recent progress in our understanding of the role of the indoor environment in asthma, focusing on the special role of cat allergens.201222081090
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
elimination of borrelia burgdorferi and anaplasma phagocytophilum in rodent reservoirs and ixodes scapularis ticks using a doxycycline hyclate-laden bait.a field trial was conducted in a lyme disease-endemic area of new jersey to determine the efficacy of a doxycyline hyclate rodent bait to prophylactically protect and cure small-mammal reservoirs and reduce infection rates in questing ixodes scapularis ticks for borrelia burgdorferi and anaplasma phagocytophilum. the doxycycline-laden bait was formulated at a concentration of 500 mg/kg and delivered during the immature tick feeding season in rodent-targeted bait boxes. the percentage of infected ...201122144454
evaluation of glycoproteins purified from adult and larval camel ticks (hyalomma dromedarii) as a candidate order to identify antigens that can help prevent camel tick infestations, three major glycoproteins (glps) about 97, 66 and 40 kda in size were purified from adult and larval egyptian ticks, hyalomma (h.) dromedarii, using a single-step purification method with con-a sepharose. the purified glps were evaluated as vaccines against camel tick infestation in rabbits. the rabbits received three intramuscular inoculations of glps (20 µg/animal) on days 0, 14, and 28. in the immunoblot analysis, se ...201121897098
First transcriptome of the testis-vas deferens-male accessory gland and proteome of the spermatophore from Dermacentor variabilis (Acari: Ixodidae).Ticks are important vectors of numerous human diseases and animal diseases. Feeding stimulates spermatogenesis, mating and insemination of male factors that trigger female reproduction. The physiology of male reproduction and its regulation of female development are essentially a black box. Several transcriptomes have catalogued expression of tick genes in the salivary glands, synganglion and midgut but no comprehensive investigation has addressed male reproduction and mating. Consequently, a ne ...201121949745
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
a survey on endoparasites and ectoparasites of stray cats from mashhad (iran) and association with risk there appeared to be no data available on parasite infection of stray cats in the region and considering the potential threat of stray cats for animal and public health, the present study was carried out using biological samples and necropsy finding collected from cats captured in mashhad city in the northeast of iran. from a total 52 stray cats examined, 18 (34.6%) were male and 34 (65.4%) were female. ten species of endoparasites including helminthes and protozoa and two species of ectopara ...201123024505
Infection prevalences of common tick-borne pathogens in adult lone star ticks (Amblyomma americanum) and American dog ticks (Dermacentor variabilis) in Kentucky.Rocky Mountain spotted fever, Lyme disease, and ehrlichiosis are tick-borne diseases that are reported annually in Kentucky. We conducted a survey to describe infection prevalence of tick-borne pathogens in Amblyomma americanum and Dermacentor variabilis ticks collected in Kentucky. During 2007-2008, we collected 287 ticks (179 D. variabilis and 108 A. americanum) from canine, feral hog, horse, raccoon, white-tailed deer, and human hosts in six counties in Kentucky. Ticks were screened for Ricke ...201121976578
anaplasma odocoilei sp. nov. (family anaplasmataceae) from white-tailed deer (odocoileus virginianus).recently, an undescribed anaplasma sp. (also called ehrlichia-like sp. or wtd agent) was isolated in ise6 tick cells from captive white-tailed deer. the goal of the current study was to characterize this organism using a combination of experimental infection, morphologic, serologic, and molecular studies. each of 6 experimentally inoculated white-tailed deer fawns (odocoileus virginianus) became chronically infected (100+ days) with the anaplasma sp. by inoculation of either infected whole blood ...201223276749
abstracts of the fourth international symposium on molecular insect science. may 28-june 2, 2002. tucson, arizona, usa. 200215455051
clinical manifestations of tick-borne infections in children. 200010882645
arbobacteria - pathogens transmittable by arthropods. 200821512627
larval keys to the genera of ixodidae (acari) and species of ixodes (latreille) ticks established in california, hard (ixodidae) ticks transmit at least 8 zoonotic disease agents (1 virus, 6 bacteria, 1 protozoan) to humans or other animals. the correct taxonomic identification of all 3 parasitic stages (larvae, nymphs, adults) of ticks is integral to understanding host-tick associations and disease dynamics, but immature ticks, especially the larvae, can be difficult to identify. here, we present larval keys to the 4 genera of ixodidae (dermacentorkoch, 1844; haemaphysaliskoch, 1844; ixodes ...200820027236
babesia and its hosts: adaptation to long-lasting interactions as a way to achieve efficient transmission.babesia, the causal agent of babesiosis, are tick-borne apicomplexan protozoa. true babesiae (babesia genus sensu stricto) are biologically characterized by direct development in erythrocytes and by transovarial transmission in the tick. a large number of true babesia species have been described in various vertebrate and tick hosts. this review presents the genus then discusses specific adaptations of babesia spp. to their hosts to achieve efficient transmission. the main adaptations lead to lon ...200919379662
arbobacteria - pathogens transmittable by arthropods. 200921048822
the role of saliva in tick feeding.when attempting to feed on their hosts, ticks face the problem of host hemostasis (the vertebrate mechanisms that prevent blood loss), inflammation (that can produce itching or pain and thus initiate defensive behavior on their hosts) and adaptive immunity (by way of both cellular and humoral responses). against these barriers, ticks evolved a complex and sophisticated pharmacological armamentarium, consisting of bioactive lipids and proteins, to assist blood feeding. recent progress in transcri ...200919273185
subversion of complement by hematophagous parasites.the complement system is a crucial part of innate and adaptive immunity which exerts a significant evolutionary pressure on pathogens. it has selected for those pathogens, mainly microorganisms but also parasites, that have evolved countermeasures. the characterization of how pathogens evade complement attack is a rapidly developing field of current research. in recent years, multiple complement evasion strategies have been characterized. in this review, we focus on complement escape mechanisms ...200918762211
prevention of lyme disease and other tick-borne infections.prevention is the best method for avoiding potentially serious complications of lyme and other tick-borne diseases. in this article, we discuss preventative measures that can be used by individuals or communities. among the topics discussed are personal protective measures, tick reduction, reservoir reduction, and vaccination. additionally, new preventative measures that are in development-including new lyme disease vaccines, antitick vaccines, and reservoir-targeted vaccination-are discussed.200818755380
evaluation of 4-poster acaricide applicators to manage tick populations associated with disease risk in a tennessee retirement 1993, four residents of a retirement community in middle tennessee were hospitalized with symptoms of ehrlichiosis causing community managers to implement mitigation methods to reduce tick numbers. for the past four years, managers have utilized 4-poster acaricide applicators that aim to reduce disease risk to residents by killing ticks that feed on deer. to determine the efficacy of this technique, we assessed amblyomma americanum abundance in the vicinity of the devices by dragging 400 m ve ...201122129412
evolution, expansion and expression of the kunitz/bpti gene family associated with long-term blood feeding in ixodes scapularis.abstract: background: recent studies of the tick saliva transcriptome have revealed the profound role of salivary proteins in blood feeding. kunitz/bpti proteins are abundant in the salivary glands of ticks and perform multiple functions in blood feeding, such as inhibiting blood coagulation, regulating host blood supply and disrupting host angiogenesis. however, kunitz/bpti proteins in soft and hard ticks have different functions and molecular mechanisms. how these differences emerged and whet ...201222244187
meeting the challenges of on-host and off-host water balance in blood-feeding this review, we describe water balance requirements of blood-feeding arthropods, particularly contrasting dehydration tolerance during the unfed, off-host state and the challenges of excess water that accompany receipt of the bloodmeal. most basic water balance characteristics during the off-host stage are applicable to other terrestrial arthropods, as well. a well-coordinated suite of responses enable arthropods to conserve water resources, enhance their desiccation tolerance, and increase t ...201020206630
bioinformatics and expression analyses of the ixodes scapularis tick cystatin family.the cystatins are inhibitors of papain- and legumain-like cysteine proteinases, classified in merops subfamilies i25a-i25c. this study shows that 84 % (42/50) of tick cystatins are putatively extracellular in subfamily i25b and the rest are putatively intracellular in subfamily i25a. on the neighbor joining phylogeny guide tree, subfamily i25a members cluster together, while subfamily i25b cystatins segregate among prostriata or metastriata ticks. two ixodes scapularis cystatins, aay66864 and is ...201223053911
implication of haematophagous arthropod salivary proteins in host-vector interactions.the saliva of haematophagous arthropods contains an array of anti-haemostatic, anti-inflammatory and immunomodulatory molecules that contribute to the success of the blood meal. the saliva of haematophagous arthropods is also involved in the transmission and the establishment of pathogens in the host and in allergic responses. this survey provides a comprehensive overview of the pharmacological activity and immunogenic properties of the main salivary proteins characterised in various haematophag ...201121951834
tick cell culture isolation and growth of rickettsia raoultii from dutch dermacentor reticulatus ticks.tick cell lines play an important role in research on ticks and tick-borne pathogenic and symbiotic microorganisms. in an attempt to derive continuous dermacentor reticulatus cell lines, embryo-derived primary cell cultures were set up from eggs laid by field ticks originally collected as unfed adults in the netherlands and maintained for up to 16 months. after several months, it became evident that cells in the primary cultures were infected with a rickettsia-like intracellular organism. supern ...201223140894
rnai in arthropods: insight into the machinery and applications for understanding the pathogen-vector interface.the availability of genome sequencing data in combination with knowledge of expressed genes via transcriptome and proteome data has greatly advanced our understanding of arthropod vectors of disease. not only have we gained insight into vector biology, but also into their respective vector-pathogen interactions. by combining the strengths of postgenomic databases and reverse genetic approaches such as rnai, the numbers of available drug and vaccine targets, as well as number of transgenes for su ...201224705082
analysis of babesia bovis infection-induced gene expression changes in larvae from the cattle tick, rhipicephalus (boophilus) microplus.cattle babesiosis is a tick-borne disease of cattle that has severe economic impact on cattle producers throughout the world's tropical and subtropical countries. the most severe form of the disease is caused by the apicomplexan, babesia bovis, and transmitted to cattle through the bite of infected cattle ticks of the genus rhipicephalus, with the most prevalent species being rhipicephalus (boophilus) microplus. we studied the reaction of the r. microplus larval transcriptome in response to infe ...201222871314
natural product studies of u.s. endangered plants: volatile components of lindera melissifolia (lauraceae) repel mosquitoes and ticks.the number of endangered plant species in the u.s. is significant, yet studies aimed towards utilizing these plants are limited. ticks and mosquitoes are vectors of significant pathogenic diseases of humans. repellents are critical means of personal protection against biting arthropods and disease transmission. the essential oil and solvent extracts from lindera melissifolia (walt.) blume (lauraceae) (pondberry) drupes were gathered and analyzed by gc and gc-ms. the essential oil obtained from t ...201222704653
borrelia burgdorferi infections in the united is becoming increasingly evident that the clinical presentation of infection with borrelia burgdorferi varies greatly between different parts of the world. a growing number of european and asian isolates of lyme borreliae, differing from the american strain of borrelia burgdorferi, have been identified in several different disorders. in light of the increasing number of reports describing an association between various cutaneous disorders and infection with borrelia burgdorferi and the contro ...201222916311
survey of borreliae in ticks, canines, and white-tailed deer from arkansas, the eastern and upper midwestern regions of north america, ixodes scapularis (l.) is the most abundant tick species encountered by humans and the primary vector of b. burgdorferi, whereas in the southeastern region amblyomma americanum (say) is the most abundant tick species encountered by humans but cannot transmit b. burgdorferi. surveys of borreliae in ticks have been conducted in the southeastern united states and often these surveys identify b. lonestari as the primary borrelia species, ...201222781030
co2 flagging - an improved method for the collection of questing ticks.most epidemiological studies on tick-borne pathogens involve collection of ticks from the environment. an efficient collection method is essential for large sample pools. our main aim was to evaluate the efficacy of a new method, where traditional flagging was enhanced by the use of co2 dispersed into the white flannel. the co2 was spread through a rubber hose network inserted into the flag blanket. the research was conducted in spring, in march-april 2011 in two locations from cluj county, roma ...201222720872
composition and seasonal variation of rhipicephalus turanicus and rhipicephalus sanguineus bacterial communities.a 16s rrna gene approach, including 454 pyrosequencing and quantitative pcr (qpcr), was used to describe the bacterial community in rhipicephalus turanicus and to evaluate the dynamics of key bacterial tenants of adult ticks during the active questing season. the bacterial community structure of rh. turanicus was characterized by high dominance of coxiella and rickettsia and extremely low taxonomic diversity. parallel diagnostic pcr further revealed a novel coxiella species which was present and ...201222467507
empiric antibiotic treatment of erythema migrans-like skin lesions as a function of geography: a clinical and cost effectiveness modeling study.the skin lesion of early lyme disease, erythema migrans (em), is so characteristic that routine practice is to treat all such patients with antibiotics. because other skin lesions may resemble em, it is not known whether presumptive treatment of em is appropriate in regions where lyme disease is rare. we constructed a decision model to compare the cost and clinical effectiveness of three strategies for the management of em: treat all, observe, and serology as a function of the probability that a ...201324107201
tick salivary secretion as a source of antihemostatics.ticks are mostly obligatory blood feeding ectoparasites that have an impact on human and animal health. in addition to direct damage due to feeding, some tick species serve as the vectors for the causative agents of several diseases, such as the spirochetes of the genus borrelia causing lyme disease, the virus of tick-borne encephalitis, various rickettsial pathogens or even protozoan parasites like babesia spp. hard ticks are unique among bloodfeeders because of their prolonged feeding period t ...201222564820
single-tube real-time pcr assay for differentiation of ixodes affinis and ixodes scapularis.ixodes affinis neumann (1899) and ixodes scapularis say (1821) are tick vectors of the etiologic agent of lyme disease, borrelia burgdorferi sensu stricto. ixodes affinis and i. scapularis are morphologically very similar, and as they are sympatric in the mid- and south-atlantic u.s. coastal states, their accurate identification is crucial to studies of disease and vector ecology in this area. this work describes a rapid, single-tube sybr(®) green-based real-time pcr assay for differentiation of ...201324192510
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