| prevalence of rickettsia species in canadian populations of dermacentor andersoni and d. variabilis. | we determined the prevalence of rickettsiae in dermacentor adults at 15 localities in canada. rickettsia rickettsii was not detected in any tick, whereas rickettsia peacockii was present in 76% of dermacentor andersoni adults and rickettsia montanensis in 8% of dermacentor variabilis adults. this host specificity was maintained in localities where both tick species occurred in sympatry. | 2009 | 19151178 |
| independence of anaplasma marginale strains with high and low transmission efficiencies in the tick vector following simultaneous acquisition by feeding on a superinfected mammalian reservoir host. | strain superinfection occurs when a second pathogen strain infects a host already carrying a primary strain. anaplasma marginale superinfection occurs when the second strain carries a variant repertoire different from that of the primary strain, and the epidemiologic consequences depend on the relative efficiencies of tick-borne transmission of the two strains. following strain superinfection in the reservoir host, we tested whether the presence of two a. marginale (sensu lato) strains that diff ... | 2009 | 19188360 |
| rickettsia phylogenomics: unwinding the intricacies of obligate intracellular life. | completed genome sequences are rapidly increasing for rickettsia, obligate intracellular alpha-proteobacteria responsible for various human diseases, including epidemic typhus and rocky mountain spotted fever. in light of phylogeny, the establishment of orthologous groups (ogs) of open reading frames (orfs) will distinguish the core rickettsial genes and other group specific genes (class 1 ogs or c1ogs) from those distributed indiscriminately throughout the rickettsial tree (class 2 og or c2ogs) ... | 2008 | 19194535 |
| dermatologic changes induced by repeated ixodes scapularis bites and implications for prevention of tick-borne infection. | previous studies in rodents and people have demonstrated that repeated tick exposure is associated with reduced borrelia burgdorferi transmission but the mechanism of prevention remains unclear. we examined the acute histopathologic reactions to initial and repeated ixodes scapularis bites in balb/c mice and in people. skin biopsies of balb/c mice infested for the first time by i. scapularis nymphs revealed vascular dilatation and an accumulation of inflammatory cells adjacent to the bite site b ... | 2009 | 19196014 |
| allopatric speciation in ticks: genetic and reproductive divergence between geographic strains of rhipicephalus (boophilus) microplus. | the cattle tick, rhipicephalus (boophilus) microplus, economically impact cattle industry in tropical and subtropical regions of the world. the morphological and genetic differences among r. microplus strains have been documented in the literature, suggesting that biogeographical and ecological separation may have resulted in boophilid ticks from america/africa and those from australia being different species. to test the hypothesis of the presence of different boophilid species, herein we perfo ... | 2009 | 19243585 |
| nonrandom distribution of vector ticks (dermacentor variabilis) infected by francisella tularensis. | the island of martha's vineyard, massachusetts, is the site of a sustained outbreak of tularemia due to francisella tularensis tularensis. dog ticks, dermacentor variabilis, appear to be critical in the perpetuation of the agent there. tularemia has long been characterized as an agent of natural focality, stably persisting in characteristic sites of transmission, but this suggestion has never been rigorously tested. accordingly, we sought to identify a natural focus of transmission of the agent ... | 2009 | 19247435 |
| cell lines from the soft tick ornithodoros moubata. | primary cell cultures (n = 16) were initiated from tissues of embryonic and neonatal larval ornithodoros moubata following methods developed for hard ticks. after maintenance for 20-25 months in vitro, cell multiplication commenced in surviving cultures, leading to the establishment of six cell lines designated ome/ctvm21, 22, 24, 25, 26 and 27. all lines are maintained at 28 degrees c, with subculture at 2-8 week intervals. the cultures comprise heterogeneous populations of large cells of 15-10 ... | 2009 | 19252822 |
| ecological fitness and strategies of adaptation of bartonella species to their hosts and vectors. | bartonella spp. are facultative intracellular bacteria that cause characteristic hostrestricted hemotropic infections in mammals and are typically transmitted by blood-sucking arthropods. in the mammalian reservoir, these bacteria initially infect a yet unrecognized primary niche, which seeds organisms into the blood stream leading to the establishment of a long-lasting intra-erythrocytic bacteremia as the hall-mark of infection. bacterial type iv secretion systems, which are supra-molecular tra ... | 2009 | 19284965 |
| a novel sphingomyelinase-like enzyme in ixodes scapularis tick saliva drives host cd4 t cells to express il-4. | tick feeding modulates host immune responses. tick-induced skewing of host cd4(+) t cells towards a th2 cytokine profile facilitates transmission of tick-borne pathogens that would otherwise be neutralized by th1 cytokines. tick-derived factors that drive this th2 response have not previously been characterized. in the current study, we examined an i. scapularis cdna library prepared at 18-24 h of feeding and identified and expressed a tick gene with homology to loxosceles spider venom proteins ... | 2009 | 19292772 |
| cattle can develop immunity to paralysis caused by dermacentor andersoni. | cattle exposed to a paralyzing strain of dermacentor andersoni (stiles) were all paralyzed during an initial exposure, but the incidence of paralysis decreased to 17 and 0% after two subsequent exposures to virulent flat ticks. cattle with a single exposure to paralyzing ticks became paralyzed when challenged with ticks that had been prefed on cattle. western blots indicated that cattle developed antibody responses to 13 antigens in paralyzing tick saliva. the likelihood of paralysis was inverse ... | 2009 | 19351088 |
| the relationship between spotted fever group rickettsiae and ixodid ticks. | spotted fever group rickettsiae are predominantly transmitted by ticks. rickettsiae have developed many strategies to adapt to different environmental conditions, including those within their arthropod vectors and vertebrate hosts. the tick-rickettsiae relationship has been a point of interest for many researchers, with most studies concentrating on the role of ticks as vectors. unfortunately, less attention has been directed towards the relationship of rickettsiae with tick cells, tissues, and ... | 2009 | 19358804 |
| reviewing molecular adaptations of lyme borreliosis spirochetes in the context of reproductive fitness in natural transmission cycles. | lyme borreliosis (lb) is caused by a group of pathogenic spirochetes - most often borrelia burgdorferi, b. afzelii, and b. garinii - that are vectored by hard ticks in the ixodes ricinus-persulcatus complex, which feed on a variety of mammals, birds, and lizards. although lb is one of the best-studied vector-borne zoonoses, the annual incidence in north america and europe leads other vector-borne diseases and continues to increase. what factors make the lb system so successful, and how can resea ... | 2009 | 19368764 |
| analysis of the rickettsia africae genome reveals that virulence acquisition in rickettsia species may be explained by genome reduction. | the rickettsia genus includes 25 validated species, 17 of which are proven human pathogens. among these, the pathogenicity varies greatly, from the highly virulent r. prowazekii, which causes epidemic typhus and kills its arthropod host, to the mild pathogen r. africae, the agent of african tick-bite fever, which does not affect the fitness of its tick vector. | 2009 | 19379498 |
| limited transcriptional responses of rickettsia rickettsii exposed to environmental stimuli. | rickettsiae are strict obligate intracellular pathogens that alternate between arthropod and mammalian hosts in a zoonotic cycle. typically, pathogenic bacteria that cycle between environmental sources and mammalian hosts adapt to the respective environments by coordinately regulating gene expression such that genes essential for survival and virulence are expressed only upon infection of mammals. temperature is a common environmental signal for upregulation of virulence gene expression although ... | 2009 | 19440298 |
| generation of antigenic variants via gene conversion: evidence for recombination fitness selection at the locus level in anaplasma marginale. | multiple bacterial and protozoal pathogens utilize gene conversion to generate antigenically variant surface proteins to evade immune clearance and establish persistent infection. both the donor alleles that encode the variants following recombination into an expression site and the donor loci themselves are under evolutionary selection: the alleles that encode variants that are sufficiently antigenically unique yet retain growth fitness and the loci that allow efficient recombination. we examin ... | 2009 | 19487473 |
| the immunomodulatory action of sialostatin l on dendritic cells reveals its potential to interfere with autoimmunity. | sialostatin l (sialol) is a secreted cysteine protease inhibitor identified in the salivary glands of the lyme disease vector ixodes scapularis. in this study, we reveal the mechanisms of sialol immunomodulatory actions on the vertebrate host. lps-induced maturation of dendritic cells from c57bl/6 mice was significantly reduced in the presence of sialol. although ova degradation was not affected by the presence of sialol in dendritic cell cultures, cathepsin s activity was partially inhibited, l ... | 2009 | 19494265 |
| genetic variation in the 16s mitochondrial dna gene of two canadian populations of dermacentor andersoni (acari: ixodidae). | the rocky mountain wood tick, dermacentor andersoni stiles, 1908, is of medical and veterinary importance because it can transmit pathogenic agents to humans, domestic livestock, and wildlife. the preferred attachment sites of d. andersoni adults and their ability to induce paralysis in hosts vary among populations, which may have a genetic basis. in this study, polymerase chain reaction (pcr)-single-strand conformation polymorphism (sscp) analyses and dna sequencing were used to determine the g ... | 2009 | 19496416 |
| transovarial transmission of francisella-like endosymbionts and anaplasma phagocytophilum variants in dermacentor albipictus (acari: ixodidae). | dermacentor albipictus (packard) is a north american tick that feeds on cervids and livestock. it is a suspected vector of anaplasmosis in cattle, but its microbial flora and vector potential remain underevaluated. we screened d. albipictus ticks collected from minnesota white-tailed deer (odocoileus virginianus) for bacteria of the genera anaplasma, ehrlichia, francisella, and rickettsia using polymerase chain reaction (pcr) gene amplification and sequence analyses. we detected anaplasma phagoc ... | 2009 | 19496436 |
| microarray analysis of gene expression changes in feeding female and male lone star ticks, amblyomma americanum (l). | a collection of est clones from female tick amblyomma americanum salivary glands was hybridized to rna from different feeding stages of female tick salivary glands and from unfed or feeding adult male ticks. in the female ticks, the expression patterns changed dramatically upon starting feeding, then changed again towards the end of feeding. on beginning feeding, genes possibly involved in survival on the host increased in expression as did many housekeeping genes. as feeding progressed, some of ... | 2009 | 19514082 |
| status of the "east side hypothesis" (transovarial interference) 25 years later. | rocky mountain spotted fever (rmsf) cases in the notorious bitterroot valley outbreak of the early 20th century were peculiarly distributed, with virtually all reported from the west side of the valley. such a distribution remained unexplained until burgdorfer and colleagues (1981) reported that endosymbiotic rickettsiae were prevalent in wood ticks on the east side of the bitterroot river valley but not on the west side. the "east side agent" was said to prevent the transovarial transmission of ... | 2009 | 19538274 |
| silencing of genes involved in anaplasma marginale-tick interactions affects the pathogen developmental cycle in dermacentor variabilis. | the cattle pathogen, anaplasma marginale, undergoes a developmental cycle in ticks that begins in gut cells. transmission to cattle occurs from salivary glands during a second tick feeding. at each site of development two forms of a. marginale (reticulated and dense) occur within a parasitophorous vacuole in the host cell cytoplasm. however, the role of tick genes in pathogen development is unknown. four genes, found in previous studies to be differentially expressed in dermacentor variabilis ti ... | 2009 | 19607704 |
| metapopulation structure for perpetuation of francisella tularensis tularensis. | outbreaks of type a tularemia due to francisella tularensis tularensis are typically sporadic and unstable, greatly hindering identification of the determinants of perpetuation and human risk. martha's vineyard, massachusetts has experienced an outbreak of type a tularemia which has persisted for 9 years. this unique situation has allowed us to conduct long-term eco-epidemiologic studies there. our hypothesis is that the agent of type a tularemia is perpetuated as a metapopulation, with many sma ... | 2009 | 19627585 |
| ehrlichia chaffeensis infections in drosophila melanogaster. | ehrlichia chaffeensis is an obligate, intracellular bacterium, transmitted by the tick amblyomma americanum, and is the causative agent of human monocytic ehrlichiosis infections. we previously demonstrated that e. chaffeensis is capable of growing in drosophila s2 cells. therefore, we tested the hypothesis that e. chaffeensis can infect adult drosophila melanogaster. adult drosophila organisms were experimentally challenged with intra-abdominal injections of bacteria. ehrlichia-infected flies s ... | 2009 | 19687202 |
| epidemiology of colorado tick fever in montana, utah, and wyoming, 1995-2003. | colorado tick fever (ctf) is a biphasic, febrile illness caused by a coltivirus and transmitted by the rocky mountain wood tick, dermacentor andersoni, in the western united states and canada. symptoms generally include acute onset of fever, headache, chills, and myalgias; illness often lasts for 3 weeks or more. laboratory-confirmed cases of ctf were identified from public health department records in montana, utah, and wyoming, and from the centers for disease control and prevention diagnostic ... | 2010 | 19725767 |
| blood feeding by the rocky mountain spotted fever vector, dermacentor andersoni, induces interleukin-4 expression by cognate antigen responding cd4+ t cells. | abstract: | 2009 | 19814808 |
| superinfection occurs in anaplasma phagocytophilum infected sheep irrespective of infection phase and protection status. | anaplasma phagocytophilum infection in domestic ruminants is widespread in the coastal areas of southern norway. the bacteria may persist in mammalian hosts. several genetic variants of a. phagocytophilum exist. in the present study, we investigate whether superinfection occurs in the acute and persistent phase of the infection. | 2009 | 19857248 |
| the survival of leptospira (spirochaeta) icterohaemorrhagiae in nature; observations concerning microchemical reactions and intermediary hosts. | 1. leptospira icterohaemorrhagiae is unable to grow in the urine, either with or without the addition of suitable culture ingredients, the acidity of the urine being detrimental to the growth. it survives less than 24 hours, unless the urine is neutralized or slightly alkalized, when the period of survival is somewhat longer. if suitable nutrient ingredients are added to the neutralized or slightly alkalized urine, the organism is able to grow for about 10 days, after which multiplication ceases ... | 1918 | 19868229 |
| cultivation of rickettsia-like microorganisms from the rocky mountain spotted fever tick, dermacentor andersoni. | a systematic study of 74 ticks, the infectivity or non-infectivity of which was determined by biting experiments, inoculation of emulsions, and specific immunity tests, showed the presence in some instances of several types of microorganisms morphologically resembling the inciting microorganism of spotted fever. the most frequently isolated was b. rickettsiformis, n. sp., those less commonly encountered were b. pseudoxerosis, n. sp., and b. equidistans, n. sp. these organisms are non-pathogenic ... | 1926 | 19869142 |
| a filter-passing virus obtained from dermacentor andersoni. | an invisible, filter-passing virus, pathogenic for the guinea pig, and capable of cultivation on special media for at least seven generations, has been isolated from a tick of the species dermacentor andersoni. one of two monkeys (macacus rhesus) inoculated became infected, and in one rabbit the result was negative. the virus has been transmitted from infected guinea pigs to ticks as also in one instance by tick feeding from an infected tick to a guinea pig the presence of the virus in the tick ... | 1926 | 19869167 |
| etiology of oroya fever : v. the experimental transmission of bartonella bacilliformis by ticks (dermacentor andersoni). | experiments are reported in which bartonella bacilliformis was transmitted from infected to normal rhesus monkeys by the bite of the tick, dermacentor andersoni. a long period of feeding, both on the infected animal and on the normal animal subjected to infection, was required in order to secure positive results. the infection transmitted by the ticks was mild, but definite, as shown by the recovery of bartonella bacilliformis from the lymph nodes and blood. | 1926 | 19869219 |
| hereditary transmission of the western type of equine encephalomyelitis virus in the wood tick, dermacentor andersoni stiles. | the western type of equine encephalomyelitis virus can be passed as an hereditary infection in a tick of the family ixodidae, dermacentor andersoni stiles. under experimental conditions, this virus has been carried in this tick for two successive generations, possibly for a third, passing certainly once, and possibly twice, from the female through the eggs to the larvae. the virus-carrying larval, nymphal, and adult stages of this tick, furthermore, are capable of infecting susceptible hosts whe ... | 1941 | 19871094 |
| the experimental transmission of colorado tick fever. | 1. the symptoms, history of tick bite, characteristic fever curve, and white blood cell picture should enable the physician to make a diagnosis of colorado tick fever in nearly every case. 2. the typical white blood cell picture is a depression of the total leucocytes with a shift to the left of the granulocytes. basophilic cytoplasmic bodies appear occasionally in lymphocytes 3 to 4 days after clinical recovery. 3. the disease can be transmitted serially in human beings by parenteral injection ... | 1944 | 19871406 |
| inducing active and passive immunity in sheep to paralysis caused by dermacentor andersoni. | arcott sheep were evaluated as a model for studying active and passive immunity to tick paralysis caused by dermacentor andersoni (stiles). the incidence of tick paralysis in sheep increased from 0 at doses < or = 0.33 ticks per kg to 100% at > or = 0.8 ticks per kg. the dose required for 50% paralysis was 0.42 ticks per kg. expressing dose as a ratio of initial ticks per unit body weight removed differences in response due to sheep weight. the interval from infestation to paralysis decreased fr ... | 2009 | 19960693 |
| infection of the endothelium by members of the order rickettsiales. | the vascular endothelium is the main target of a limited number of infectious agents, rickettsia, ehrlichia ruminantium, and orientia tsutsugamushi are among them. these arthropod-transmitted obligately-intracellular bacteria cause serious systemic diseases that are not infrequently lethal. in this review, we discuss the bacterial biology, vector biology, and clinical aspects of these conditions with particular emphasis on the interactions of these bacteria with the vascular endothelium and how ... | 2009 | 19967137 |
| analysis of rickettsia typhi-infected and uninfected cat flea (ctenocephalides felis) midgut cdna libraries: deciphering molecular pathways involved in host response to r. typhi infection. | murine typhus is a flea-borne febrile illness that is caused by the obligate intracellular bacterium, rickettsia typhi. the cat flea, ctenocephalides felis, acquires r. typhi by imbibing a bloodmeal from a rickettsemic vertebrate host. to explore which transcripts are expressed in the midgut in response to challenge with r. typhi, cdna libraries of r. typhi-infected and uninfected midguts of c. felis were constructed. in this study, we examined midgut transcript levels for select c. felis serine ... | 2010 | 20017753 |
| genome sequence of the endosymbiont rickettsia peacockii and comparison with virulent rickettsia rickettsii: identification of virulence factors. | rickettsia peacockii, also known as the east side agent, is a non-pathogenic obligate intracellular bacterium found as an endosymbiont in dermacentor andersoni ticks in the western usa and canada. its presence in ticks is correlated with reduced prevalence of rickettsia rickettsii, the agent of rocky mountain spotted fever. it has been proposed that a virulent sfg rickettsia underwent changes to become the east side agent. we determined the genome sequence of r. peacockii and provide a compariso ... | 2009 | 20027221 |
| wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods. | plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ... | 2010 | 20097813 |
| rickettsial ompb promoter regulated expression of gfpuv in transformed rickettsia montanensis. | rickettsia spp. (rickettsiales: rickettsiaceae) are gram-negative, obligate intracellular, alpha-proteobacteria that have historically been associated with blood-feeding arthropods. certain species cause typhus and spotted fevers in humans, but others are of uncertain pathogenicity or may be strict arthropod endosymbionts. genetic manipulation of rickettsiae should facilitate a better understanding of their interactions with hosts. | 2010 | 20126457 |
| extraction of total nucleic acids from ticks for the detection of bacterial and viral pathogens. | ticks harbor numerous bacterial, protozoal, and viral pathogens that can cause serious infections in humans and domestic animals. active surveillance of the tick vector can provide insight into the frequency and distribution of important pathogens in the environment. nucleic-acid based detection of tick-borne bacterial, protozoan, and viral pathogens requires the extraction of both dna and rna (total nucleic acids) from ticks. traditional methods for nucleic acid extraction are limited to extrac ... | 2010 | 20180313 |
| detection of a new arsenophonus-type bacterium in canadian populations of the rocky mountain wood tick, dermacentor andersoni. | ticks of the genus dermacentor are important vectors of human and animal pathogens in north america. they also carry a variety of endosymbiotic (i.e. non-pathogenic) bacteria. the american dog tick, d. variabilis, is known to be infected with gammaproteobacteria of the genus arsenophonus. however, there have been no previous reports of arsenophonus-type bacteria in the rocky mountain wood tick, d. andersoni, a species that is sympatric with d. variabilis in the western parts of its distributiona ... | 2010 | 20186465 |
| detection of "candidatus rickettsia sp. strain argentina"and rickettsia bellii in amblyomma ticks (acari: ixodidae) from northern argentina. | ixodid ticks were collected from vegetation and from humans, wild and domestic mammals in a rural area in the semi-arid argentine chaco in late spring 2006 to evaluate their potential role as vectors of spotted fever group (sfg) rickettsiae. a total of 233 adult ticks, identified as amblyomma parvum, amblyomma tigrinum and amblyomma pseudoconcolor, was examined for rickettsia spp. we identified an sfg rickettsia of unknown pathogenicity, "candidatus rickettsia sp. strain argentina", in a. parvum ... | 2010 | 20186466 |
| tularemia, plague, yersiniosis, and tyzzer's disease in wild rodents and lagomorphs in canada: a review. | information related to infection of wild rodents or lagomorphs in canada by francisella tularensis, yersinia pestis, other yersinia spp., and clostridium piliforme was searched for this study. reports on tularemia in humans linked to these species came from diagnostic databases, literature, wildlife health specialists, and public health agencies. tularemia has been diagnosed in 8 species of wild rodent and 2 species in the genus lepus in canada. tularemia occurred in wild animals, or in humans a ... | 2009 | 20190973 |
| bartonella spp. transmission by ticks not established. | bartonella spp. infect humans and many animal species. mainly because pcr studies have demonstrated bartonella dna in ticks, some healthcare providers believe that these microorganisms are transmitted by ticks. b. henselae, in particular, is regarded as being present in and transmissible by the ixodes scapularis tick. the presence of a microbial agent within a tick, however, does not imply that the tick might transmit it during the course of blood feeding and does not confer epidemiologic import ... | 2010 | 20202410 |
| isolation of rickettsia parkeri and identification of a novel spotted fever group rickettsia sp. from gulf coast ticks (amblyomma maculatum) in the united states. | until recently, amblyomma maculatum (the gulf coast tick) had garnered little attention compared to other species of human-biting ticks in the united states. a. maculatum is now recognized as the principal vector of rickettsia parkeri, a pathogenic spotted fever group rickettsia (sfgr) that causes an eschar-associated illness in humans that resembles rocky mountain spotted fever. a novel sfgr, distinct from other recognized rickettsia spp., has also been detected recently in a. maculatum specime ... | 2010 | 20208020 |
| association of pathogen strain-specific gene transcription and transmission efficiency phenotype of anaplasma marginale. | efficient transmission of pathogens by an arthropod vector is influenced by the ability of the pathogen to replicate and develop infectiousness within the arthropod host. while the basic life cycle of development within and transmission from the arthropod vector are known for many bacterial and protozoan pathogens, the determinants of transmission efficiency are largely unknown and represent a significant gap in our knowledge. the st. maries strain of anaplasma marginale is a high-transmission-e ... | 2010 | 20308303 |
| phagocytosis of the lyme disease spirochete, borrelia burgdorferi, by cells from the ticks, ixodes scapularis and dermacentor andersoni, infected with an endosymbiont, rickettsia peacockii. | tick cell lines were used to model the effects of endosymbiont infection on phagocytic immune responses. the lines tested for their ability to phagocytose the lyme disease spirochete, borrelia burgdorferi (spirochaetales: spirochaetaceae), were ise6 and ide12 from the black-legged tick, ixodes scapularis say (acari: ixodidae) and dae15 from the rocky mountain wood tick, dermacentor andersoni stiles. rickettsia peacockii (rickettsiales: rickettsiaceae), an endosymbiont of d. andersoni, was used a ... | 2007 | 20331397 |
| francisella acid phosphatases inactivate the nadph oxidase in human phagocytes. | francisella tularensis contains four putative acid phosphatases that are conserved in francisella novicida. an f. novicida quadruple mutant (acpa, acpb, acpc, and hap [deltaabch]) is unable to escape the phagosome or survive in macrophages and is attenuated in the mouse model. we explored whether reduced survival of the deltaabch mutant within phagocytes is related to the oxidative response by human neutrophils and macrophages. f. novicida and f. tularensis subspecies failed to stimulate reactiv ... | 2010 | 20348422 |
| tick paralysis caused by dermacentor andersoni (acari: ixodidae) is a heritable trait. | the heritability of the ability to cause paralysis was examined in crosses of virulent and avirulent dermacentor andersoni (stiles) (acari: ixodidae). virulence was assessed using hamster bioassay. paralysis was caused by the virulent parental strain but not by the avirulent parental strain. four crosses were made: avirulent female x avirulent male (aa cross), virulent female x virulent male (vv cross), avirulent female x virulent male (av cross), and virulent female x avirulent male (va cross). ... | 2010 | 20380302 |
| coxiella burnetii in humans and ticks in rural senegal. | q fever is a worldwide zoonotic disease caused by coxiella burnetii. epidemiologically, animals are considered reservoirs and humans incidental hosts. | 2010 | 20386603 |
| identification of anaplasma marginale proteins specifically upregulated during colonization of the tick vector. | the transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. we used an unbiased proteomic screen to identify anaplasma marginale proteins specifically upregulated in the tick compared to the mammalian host. comparative mass spect ... | 2010 | 20439479 |
| persistence of buggy creek virus (togaviridae, alphavirus) for two years in unfed swallow bugs (hemiptera: cimicidae: oeciacus vicarius). | alphaviruses (togaviridae) have rarely been found to persist for long in the adult insects that serve as their vectors. the ectoparasitic swallow bug (hemiptera: cimicidae: oeciacus vicarius horvath), the vector for buggy creek virus (bcrv; togaviridae, alphavirus), lives year-round in the mud nests of its host, the cliff swallow (petrochelidon pyrrhonota vieillot). we measured the prevalence of bcrv in swallow bugs at sites with cliff swallows present and at the same sites after cliff swallows ... | 2010 | 20496591 |
| transmission cycles of borrelia burgdorferi and b. bissettii in relation to habitat type in northwestern california. | this study was undertaken to determine which rodent species serve as primary reservoirs for the lyme disease spirochete borrelia burgdorferi in commonly occurring woodland types in inland areas of northwestern california, and to examine whether chaparral or grassland serve as source habitats for dispersal of b. burgdorferi- or b. bissettii-infected rodents into adjacent woodlands. the western gray squirrel (sciurus griseus) was commonly infected with b. burgdorferi in oak woodlands, whereas exam ... | 2009 | 20514140 |
| the expression of genes coding for distinct types of glycine-rich proteins varies according to the biology of three metastriate ticks, rhipicephalus (boophilus) microplus, rhipicephalus sanguineus and amblyomma cajennense. | ticks secrete a cement cone composed of many salivary proteins, some of which are rich in the amino acid glycine in order to attach to their hosts' skin. glycine-rich proteins (grps) are a large family of heterogeneous proteins that have different functions and features; noteworthy are their adhesive and tensile characteristics. these properties may be essential for successful attachment of the metastriate ticks to the host and the prolonged feeding necessary for engorgement. in this work, we an ... | 2010 | 20529354 |
| 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 ... | 2010 | 20650005 |
| anaplasma marginale infection with persistent high-load bacteremia induces a dysfunctional memory cd4+ t lymphocyte response but sustained high igg titers. | control of blood-borne infections is dependent on antigen-specific effector and memory t cells and high-affinity igg responses. in chronic infections characterized by a high antigen load, it has been shown that antigen-specific t and b cells are vulnerable to downregulation and apoptosis. anaplasma marginale is a persistent infection of cattle characterized by acute and chronic high-load bacteremia. we previously showed that cd4(+) t cells primed by immunization with an a. marginale outer membra ... | 2010 | 20943884 |
| evaluation of rickettsia japonica pathogenesis and reservoir potential in dogs by experimental inoculation and epidemiologic survey. | rickettsia japonica pathogenesis and reservoir potential in dogs were evaluated by both experimental inoculation and epidemiologic survey. in the experimental inoculation study, dogs 1 and 2 were pretreated with an immunosuppressive dose of cyclosporine 14 days before inoculation and became ill after exposure to r. japonica. dogs exhibited clinical signs, including fever, anorexia, depression, and decreased water consumption, between 36 and 96 h after inoculation, but these signs disappeared spo ... | 2010 | 20980481 |
| tick paralysis in beef cattle due to dermacentor andersoni. | | 1945 | 21009481 |
| an update on bovine anaplasmosis (anaplasma marginale) in canada. | | 2010 | 21037882 |
| rhipicephalus microplus salivary gland molecules induce differential cd86 expression in murine macrophages. | abstract: | 2010 | 21054882 |
| stability and tick transmission phenotype of gfp-transformed anaplasma marginale through a complete in vivo infection cycle. | we tested the stability and tick transmission phenotype of transformed anaplasma marginale through a complete in vivo infection cycle. similar to the wild type, the gfp-transformed a. marginale strain established infection in cattle, a natural reservoir host, and persisted in immune competent animals. the tick infection rates for the transformed a. marginale and the wild type were the same. however, there were significantly lower levels of the transformed a. marginale than of the wild type in th ... | 2010 | 21057014 |
| identification of anaplasma marginale outer membrane protein antigens conserved between a. marginale sensu stricto strains and the live a. marginale subsp. centrale vaccine. | live vaccination with anaplasma marginale subsp. centrale (synonym for anaplasma centrale) induces protection against severe disease upon challenge with a. marginale sensu stricto strains. despite over a century of field use, the targets of protective immunity remained unknown. using a broad proteomic approach, we identified the proteins in a challenge sensu stricto strain that were bound by the relevant antibody isotype induced by live vaccination with anaplasma marginale subsp. centrale. a cor ... | 2010 | 21189322 |
| 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 ... | 2011 | 21211038 |
| short report: new spotted fever group rickettsia in a rhipicephalus turanicus tick removed from a child in eastern sicily, italy. | a new genotype of spotted fever group rickettsia (sfgr) was identified in rhipicephalus turanicus from eastern sicily. on the basis of current molecular criteria, the genetic characteristics obtained from multiple locus sequence typing satisfy the requirements for candidatus status of this sfgr. further detection and identification of this sfgr during entomological and clinical surveys will be required to establish the prevalence of this rickettsia and its potential pathogenicity for humans. | 2011 | 21212209 |
| isolation of a rickettsial pathogen from a non-hematophagous arthropod. | rickettsial diversity is intriguing in that some species are transmissible to vertebrates, while others appear exclusive to invertebrate hosts. of particular interest is rickettsia felis, identifiable in both stored product insect pests and hematophagous disease vectors. to understand rickettsial survival tactics in, and probable movement between, both insect systems will explicate the determinants of rickettsial pathogenicity. towards this objective, a population of liposcelis bostrychophila, c ... | 2011 | 21283549 |
| complementation of rickettsia rickettsii rela/spot restores a nonlytic plaque phenotype. | spotted fever group rickettsiae are known to produce distinct plaque phenotypes. strains that cause lytic infections in cell culture form clear plaques, while nonlytic strains form opaque plaques in which the cells remain intact. clear plaques have historically been associated with more-virulent species or strains of spotted fever group rickettsiae. we have selected spontaneous mutant pairs from two independent strains of rickettsia rickettsii, the virulent r strain and the avirulent iowa strain ... | 2011 | 21300770 |
| novel genotypes of anaplasma bovis, "candidatus midichloria" sp. and ignatzschineria sp. in the rocky mountain wood tick, dermacentor andersoni. | bovine anaplasmosis, caused by anaplasma marginale, is a vector-borne disease that is enzootic in many parts of the usa. although dermacentor andersoni, a major vector of a. marginale, occurs in canada, the canadian cattle herds are currently considered free of bovine anaplasmosis. there have been two outbreaks of the disease in the province of saskatchewan, but these have been linked to the importation of infected animals. however, the distribution of bovine anaplasmosis may alter with range ex ... | 2011 | 21334146 |
| differences in prevalence of borrelia burgdorferi and anaplasma spp. infection among host-seeking dermacentor occidentalis, ixodes pacificus, and ornithodoros coriaceus ticks in northwestern california. | previous studies revealed that the pacific coast tick (dermacentor occidentalis) is infected occasionally with the agents of lyme disease (borrelia burgdorferi) or human granulocytic anaplasmosis (anaplasma phagocytophilum) and that it is an inefficient experimental vector of b. burgdorferi. the relationship of the pajahuello tick (ornithodoros coriaceus) to each of these bacterial zoonotic agents has not been reported. the primary bridging vector of both bacterial zoonotic agents to humans is t ... | 2010 | 21359090 |
| 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 ... | 2011 | 21362191 |
| tick paralysis in australia caused by ixodes holocyclus neumann. | ticks are obligate haematophagous ectoparasites of various animals, including humans, and are abundant in temperate and tropical zones around the world. they are the most important vectors for the pathogens causing disease in livestock and second only to mosquitoes as vectors of pathogens causing human disease. ticks are formidable arachnids, capable of not only transmitting the pathogens involved in some infectious diseases but also of inducing allergies and causing toxicoses and paralysis, wit ... | 2011 | 21396246 |
| eschar and neck lymphadenopathy caused by francisella tularensis after a tick bite: a case report. | | 2011 | 21418587 |
| 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 ... | 2011 | 21489234 |
| one health: the importance of companion animal vector-borne diseases. | abstract: the international prominence accorded the 'one health' concept of co-ordinated activity of those involved in human and animal health is a modern incarnation of a long tradition of comparative medicine, with roots in the ancient civilizations and a golden era during the 19th century explosion of knowledge in the field of infectious disease research. modern one health tends to focus on zoonotic pathogens emerging from wildlife and production animal species, but one of the most significan ... | 2011 | 21489237 |
| 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 ... | 2011 | 21529391 |
| expression of anaplasma marginale ankyrin repeat-containing proteins during infection of the mammalian host and tick vector. | transmission of tick-borne pathogens requires transition between distinct host environments with infection and replication in host-specific cell types. anaplasma marginale illustrates this transition: in the mammalian host the bacteria infects and replicates in mature (non-nucleated) erythrocytes while in the tick vector replication occurs in nucleated epithelial cells. we hypothesized that proteins containing ankyrin motifs would be expressed by a. marginale only in tick cells and would traffic ... | 2011 | 21576345 |
| 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 ... | 2011 | 21613430 |
| vector competence of the tick ixodes ricinus for transmission of bartonella birtlesii. | bartonella spp. are facultative intracellular vector-borne bacteria associated with several emerging diseases in humans and animals all over the world. the potential for involvement of ticks in transmission of bartonella spp. has been heartily debated for many years. however, most of the data supporting bartonellae transmission by ticks come from molecular and serological epidemiological surveys in humans and animals providing only indirect evidences without a direct proof of tick vector compete ... | 2011 | 21655306 |
| francisella-arthropod vector interaction and its role in patho-adaptation to infect mammals. | francisella tularensis is a gram-negative, intracellular, zoonotic bacterium, and is the causative agent of tularemia with a broad host range. arthropods such as ticks, mosquitoes, and flies maintain f. tularensis in nature by transmitting the bacteria among small mammals. while the tick is largely believed to be a biological vector of f. tularensis, transmission by mosquitoes and flies is largely believed to be mechanical on the mouthpart through interrupted feedings. however, the mechanism of ... | 2011 | 21687425 |
| 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 ... | 2011 | 21687803 |
| an elisa to detect serum antibodies to the salivary gland toxin of ixodes holocyclus neumann in dogs and rodents. | the ixodes holocyclus tick causes paralysis in up to 10,000 companion and domestic animals each year in australia. treatment requires the removal of the parasite and the administration of a commercial tick antiserum that is prepared from hyperimmune dogs. each batch of this serum is initially tested for toxin-neutralising potency in a mouse bioassay that is expensive, time consuming, and subjective. with the aim of developing a rapid in vitro assay to replace the bioassay, we used a partially pu ... | 2011 | 21687655 |
| association of different genetic types of francisella-like organisms with the rocky mountain wood tick (dermacentor andersoni) and the american dog tick (dermacentor variabilis) from localities near their northern distributional limits. | dermacentor andersoni and dermacentor variabilis from allopatric and sympatric populations near their northern distributional limits were examined for the presence of francisella species using molecular techniques that targeted 373 bp of the 16s ribosomal rna gene. although there was no evidence for the presence of francisella tularensis in any tick, francisella-like endosymbionts (fles) were common in d. andersoni and d. variabilis adults and immatures. a significantly greater proportion of fem ... | 2011 | 22179251 |
| 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 ... | 2011 | 21851864 |
| Dermacentor andersoni transmission of Francisella tularensis subsp. novicida reflects bacterial colonization, dissemination, and replication coordinated with tick feeding. | Ticks serve as biological vectors for a wide variety of bacterial pathogens which must be able to efficiently colonize specific tick tissues prior to transmission. The bacterial determinants of tick colonization are largely unknown, a knowledge gap attributed in large part to the paucity of tools to genetically manipulate these pathogens. In this study, we demonstrated that Francisella tularensis subsp. novicida, for which a complete two-allele transposon mutant library has been constructed, ini ... | 2011 | 21930762 |
| expression of heat shock and other stress response proteins in ticks and cultured tick cells in response to anaplasma spp. infection and heat shock. | ticks are ectoparasites of animals and humans that serve as vectors of anaplasma and other pathogens that affect humans and animals worldwide. ticks and the pathogens that they transmit have coevolved molecular interactions involving genetic traits of both the tick and the pathogen that mediate their development and survival. in this paper, the expression of heat shock proteins (hsps) and other stress response proteins (srps) was characterized in ticks and cultured tick cells by proteomics and t ... | 2010 | 22084679 |
| q fever: current state of knowledge and perspectives of research of a neglected zoonosis. | q fever is an ubiquitous zoonosis caused by an resistant intracellular bacterium, coxiella burnetii. in certain areas, q fever can be a severe public health problem, and awareness of the disease must be promoted worldwide. nevertheless, knowledge of coxiella burnetii remains limited to this day. its resistant (intracellular and environmental) and infectious properties have been poorly investigated. further understanding of the interactions between the infected host and the bacteria is necessary. ... | 2011 | 22194752 |
| genomotyping of coxiella burnetii using microarrays reveals a conserved genomotype for hard tick isolates. | c. burnetii is a gram-negative intracellular y-proteobacteria that causes the zoonotic disease q fever. q fever can manifest as an acute or chronic illness. different typing methods have been previously developed to classify c. burnetii isolates to explore its pathogenicity. here, we report a comprehensive genomotyping method based on the presence or absence of genes using microarrays. the genomotyping method was then tested in 52 isolates obtained from different geographic areas, different host ... | 2011 | 22046248 |
| distribution of rickettsia rickettsii in ovary cells of rhipicephalus sanguineus (latreille1806) (acari: ixodidae). | abstract: | 2011 | 22117572 |
| 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 ... | 2011 | 21955214 |
| genetics of coxiella burnetii: on the path of specialization. | coxiella burnetii is an extremely infectious, zoonotic agent that causes q fever in humans. with the exception of new zealand, the bacterium is distributed worldwide. coxiella is classified as a select agent based on its past and potential use as a bioweapon and its threat to public health. despite decades of research, we know relatively little regarding coxiella?s molecular pathogenesis, and a vaccine is not widely available. this article briefly reviews the unusual genetics of c. burnetii; a p ... | 2011 | 22082290 |
| characterization of the stop codon readthrough signal of colorado tick fever virus segment 9 rna. | termination codon readthrough is utilized as a mechanism of expression of a growing number of viral and cellular proteins, but in many cases the mrna signals that promote readthrough are poorly characterized. here, we investigated the readthrough signal of colorado tick fever virus (ctfv) segment 9 rna (seg-9). ctfv is the type-species of the genus coltivirus within the family reoviridae and is a tick-borne, double-stranded, segmented rna virus. seg-9 encodes a 36-kda protein vp9, and by readthr ... | 2011 | 22190746 |
| 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 ... | 2011 | 21976578 |
| a deep insight into the sialotranscriptome of the gulf coast tick, amblyomma maculatum. | saliva of blood sucking arthropods contains compounds that antagonize their hosts' hemostasis, which include platelet aggregation, vasoconstriction and blood clotting; saliva of these organisms also has anti-inflammatory and immunomodullatory properties. perhaps because hosts mount an active immune response against these compounds, the diversity of these compounds is large even among related blood sucking species. because of these properties, saliva helps blood feeding as well as help the establ ... | 2011 | 22216098 |
| effect of prior exposure to noninfected ticks on susceptibility of mice to lyme disease spirochetes. | to determine whether prior exposure to nearctic ixodes vector ticks protects native reservoir mice from tick-borne infection by lyme disease spirochetes, we compared their infectivities for white-footed mice and laboratory mice that had been repeatedly infested by noninfected deer ticks. nymphal ticks readily engorged on tick-exposed laboratory mice, but their feeding success on white-footed mice progressively declined. tick-borne spirochetes readily infected previously tick-infested mice. thus, ... | 1998 | 9797328 |
| clinical manifestations of tick-borne infections in children. | | 2000 | 10882645 |
| 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 ... | 2009 | 19273185 |
| meeting the challenges of on-host and off-host water balance in blood-feeding arthropods. | in 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 ... | 2010 | 20206630 |
| ixodes scapularis saliva mitigates inflammatory cytokine secretion during anaplasma phagocytophilum stimulation of immune cells. | ixodes scapularis saliva enables the transmission of infectious agents to the mammalian host due to its immunomodulatory, anesthetic and anti-coagulant properties. however, how i. scapularis saliva influences host cytokine secretion in the presence of the obligate intracellular rickettsial pathogen anaplasma phagocytophilum remains elusive. | 2012 | 23050849 |
| expansion of variant diversity associated with a high prevalence of pathogen strain superinfection under conditions of natural transmission. | superinfection occurs when a second, genetically distinct pathogen strain infects a host that has already mounted an immune response to a primary strain. for antigenically variant pathogens, the primary strain itself expresses a broad diversity of variants over time. thus, successful superinfection would require that the secondary strain express a unique set of variants. we tested this hypothesis under conditions of natural transmission in both temperate and tropical regions where, respectively, ... | 2012 | 22585962 |
| 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 ... | 2012 | 22720872 |
| why are there so few rickettsia conorii conorii-infected rhipicephalus sanguineus ticks in the wild? | rickettsia conorii conorii is the etiological agent of mediterranean spotted fever, which is transmitted by the brown dog tick, rhipicephalus sanguineus. the relationship between the rickettsia and its tick vector are still poorly understood one century after the first description of this disease. | 2012 | 22724035 |
| 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 ... | 2012 | 22467507 |