Publications

detection of a borrelia miyamotoi sensu lato relapsing-fever group spirochete from ixodes pacificus in california.	we investigated whether host-seeking nymphs and adults of the western blacklegged tick, ixodes pacificus cooley & kohls, the primary vector of lyme disease spirochetes in far-western north america, are infected naturally with relapsing-fever group spirochetes in mendocino county, california. relapsing-fever group borreliae were detected in four (1.7%) of 234 nymphal and two (0.7%) of 282 adult host-seeking i. pacificus ticks by polymerase chain reaction and sequence analysis of the 16s rrna and ...	2006	16506458
differences in the transmissibility of two anaplasma phagocytophilum strains by the north american tick vector species, ixodes pacificus and ixodes scapularis (acari: ixodidae).	the etiologic agent of granulocytic anaplasmosis, anaplasma phagocytophilum, has a circum-global distribution within the northern hemisphere and shows a host species predilection that varies by the geographic region in which the disease is found. adaptation by the bacterium to a host species potentially contributes to the variation found worldwide but this is confounded by the bacterium's relationship with its tick vectors, all of which belong to the ixodes ricinus group. we tested the hypothesi ...	2006	16550334
myd88 deficiency enhances acquisition and transmission of borrelia burgdorferi by ixodes scapularis ticks.	borrelia burgdorferi strains exhibit various degrees of infectivity and pathogenicity in mammals, which may be due to their relative ability to evade initial host immunity. innate immune cells recognize b. burgdorferi by toll-like receptors (tlrs) that use the intracellular molecule myd88 to mediate effector functions. to determine whether impaired tlr signaling enhances ixodes scapularis acquisition of b. burgdorferi, we fed nymphs on wild-type (wt) and myd88-/- mice previously infected with tw ...	2006	16552045
molecular cloning and characterization of atx1 cdna from the mole cricket, gryllotalpa orientalis.	to search for an insect homologue of antioxidant protein 1 (atx1), a mole cricket, gryllotalpa orientalis, cdna library was screened and a cdna clone, which encodes a 73 amino acid polypeptide with a predicted molecular mass of 8.0 kda and pi of 5.68, was isolated. the g. orientalis atx1 (goatx1) cdna features both a mtcxxc copper-binding site in the n-terminus and a ktgk lysine-rich region in the c-terminus. the deduced amino acid sequence of the goatx1 cdna showed 63% identity to drosophila me ...	2006	16552768
co-detection of bartonella henselae, borrelia burgdorferi, and anaplasma phagocytophilum in ixodes pacificus ticks from california, usa.	presence of bartonella dna was explored in 168 questing adult ixodes pacificus ticks from santa cruz county, california. bartonella henselae type i dna was amplified from 11 ticks (6.55%); previously, two (1.19%) were found to be infected with borrelia burgdorferi and five (2.98%) with anaplasma phagocytophilum. detection of b. henselae was not dependent on co-infection. the present study offers additional evidence that ixodes spp. ticks may act as hosts and possibly vectors for b. henselae.	2006	16584332
predicting density of ixodes pacificus nymphs in dense woodlands in mendocino county, california, based on geographic information systems and remote sensing versus field-derived data.	ixodes pacificus nymphs are the primary vectors to humans of borrelia burgdorferi, the etiologic agent of lyme disease, in california. we used a supervised classification model, based on remote sensing (rs) data from multi-seasonal landsat tm 5 images, to identify the key habitat in mendocino county where humans are exposed to i. pacificus nymphs (woodlands carpeted with leaf litter). the model, based on the normalized difference vegetation index (ndvi), brightness, and wetness, separated the ny ...	2006	16606998
an avian contribution to the presence of ixodes pacificus (acari: ixodidae) and borrelia burgdorferi on the sutter buttes of california.	birds from 45 species were sampled during three spring seasons from an isolated canyon on the sutter buttes in california for the presence of subadult stages of ixodes pacificus cooley & kohls, and for infection with borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner. these birds were found to have an infestation prevalence of 45%, a density of 1.7 ticks per bird, and an intensity of 3.8 ticks per infested bird. there was a significant difference in the i. pacificus infestations b ...	2006	16619623
geographical distribution patterns and habitat suitability models for presence of host-seeking ixodid ticks in dense woodlands of mendocino county, california.	we used drag sampling to examine the geographical distribution patterns of ixodid ticks engaging in open (non-nidicolous) host-seeking behavior in dense woodland habitats of the climatically and ecologically diverse mendocino county in north coastal california. the findings based on this sampling methodology reflect risk of human exposure to host-seeking ticks rather than the true distribution of the ticks. drag sampling in 78 sites yielded 7,860 nymphal or adult ixodes pacificus cooley & kohls, ...	2006	16619628
detection of a malaria parasite (plasmodium mexicanum) in ectoparasites (mites and ticks), and possible significance for transmission.	two species of sandflies (lutzomyia) are competent vectors of plasmodium mexicanum, a malaria parasite of lizards. the very patchy distribution of sites with high p. mexicanum prevalence in the lizards, and often low or even nil sandfly density at such sites, provoked an evaluation of 2 common lizard ectoparasites, the tick ixodes pacificus and the mite geckobiella occidentalis, as potential passive vectors. plasmodium sp.-specific polymerase chain primers were used to amplify a long segment of ...	2006	16729709
perpetuation of the lyme disease spirochete borrelia lusitaniae by lizards.	to determine whether the lyme disease spirochete borrelia lusitaniae is associated with lizards, we compared the prevalence and genospecies of spirochetes present in rodent- and lizard-associated ticks at a site where this spirochete frequently infects questing ticks. whereas questing nymphal ixodes ricinus ticks were infected mainly by borrelia afzelii, one-half of the infected adult ticks harbored b. lusitaniae at our study site. lyme disease spirochetes were more prevalent in sand lizards (la ...	2006	16820453
isolation and identification of rickettsia massiliae from rhipicephalus sanguineus ticks collected in arizona.	twenty rhipicephalus sanguineus ticks collected in eastern arizona were tested by pcr assay to establish their infection rate with spotted fever group rickettsiae. with a nested pcr assay which detects a fragment of the rickettsia genus-specific 17-kda antigen gene (htra), five ticks (25%) were found to contain rickettsial dna. one rickettsial isolate was obtained from these ticks by inoculating a suspension of a triturated tick into monolayers of vero e6 monkey kidney cells and xtc-2 clawed toa ...	2006	16885311
sylvatic maintenance of borrelia burgdorferi (spirochaetales) in northern california: untangling the web of transmission.	lyme borreliosis is associated with several genospecies of borrelia burgdorferi sensu lato (s.l.) (spirochaetales), but human disease has been associated only with borrelia burgdorferi sensu stricto (s.s.) johnson, schmid, hyde, steigerwalt & brenner in the western united states. restriction fragment length polymorphism (rflp) analysis of rrf-rrl amplicons from 124 tick and mammalian isolates from various habitats yielded 13 rflp patterns. of these patterns, six were patterns previously associat ...	2006	16892634
confirmation of tick bite by detection of antibody to ixodes calreticulin salivary protein.	ticks introduce a variety of pharmacologically active molecules into their host during attachment and feeding in order to obtain a blood meal. people who are repeatedly exposed to ticks may develop an immune response to tick salivary proteins. despite this response, people usually are unaware of having been bitten, especially if they are not repeatedly exposed to ticks. in order to develop a laboratory marker of tick exposure that would be useful in understanding the epidemiology of tick-borne i ...	2006	16928887
refractoriness of the western fence lizard (sceloporus occidentalis) to the lyme disease group spirochete borrelia bissettii.	the western fence lizard, sceloporus occidentalis, is refractory to experimental infection with borrelia burgdorferi sensu stricto, one of several lyme disease spirochetes pathogenic for humans. another member of the lyme disease spirochete complex, borrelia bissettii, is distributed widely throughout north america and a similar, if not identical, spirochete has been implicated as a human pathogen in southern europe. to determine the susceptibility of s. occidentalis to b. bissettii, 6 naïve liz ...	2006	16995383
spatial patterns of lyme disease risk in california based on disease incidence data and modeling of vector-tick exposure.	ixodes pacificus, particularly the nymphal life stage, is the primary vector to humans of the lyme disease agent borrelia burgdorferi in california. during 2004, we collected i. pacificus nymphs from 78 woodland sites in ecologically diverse mendocino county, which has a moderately high incidence of lyme disease. within this county, nymphal density was elevated in forested areas with a growing degree day range of 2,600-3,000 (10 degrees c base). using a geographic information systems approach, w ...	2006	17038692
coinfections acquired from ixodes ticks.	the pathogens that cause lyme disease (ld), human anaplasmosis, and babesiosis can coexist in ixodes ticks and cause human coinfections. although the risk of human coinfection differs by geographic location, the true prevalence of coinfecting pathogens among ixodes ticks remains largely unknown for the majority of geographic locations. the prevalence of dually infected ixodes ticks appears highest among ticks from regions of north america and europe where ld is endemic, with reported prevalences ...	2006	17041141
migratory songbirds disperse ticks across canada, and first isolation of the lyme disease spirochete, borrelia burgdorferi, from the avian tick, ixodes auritulus.	during a 3-yr comprehensive study, 196 ixodid ticks (9 species) were collected from 89 passerine birds (32 species) from 25 localities across canada to determine the distribution of avian-associated tick species and endogenous lyme disease spirochetes, borrelia burgdorferi johnson, schmid, hyde, steigerwalt, and brenner. we report the following first records of tick parasitism on avian hosts: the rabbit-associated tick, ixodes dentatus marx, from manitoba and ontario; the mouse tick, ixodes muri ...	2005	17089744
the low seroprevalence of tick-transmitted agents of disease in dogs from southern ontario and quebec.	infectious diseases caused by pathogens transmitted by ticks and other insect vectors are an important cause of morbidity and mortality in both dogs and humans throughout north america. the purpose of this study was to determine the seroprevalence of selected vector-transmitted pathogens in southern ontario and quebec. samples submitted to the vector borne disease diagnostic laboratory (vbddl) at the north carolina state university college of veterinary medicine were evaluated for antibodies to ...	2006	17217089
wild turkey (meleagris gallopavo) as a host of ixodid ticks, lice, and lyme disease spirochetes (borrelia burgdorferi sensu lato) in california state parks.	rio grande wild turkeys (meleagris gallopavo intermedia) were evaluated as potential hosts of ixodid ticks, lice, and lyme disease spirochetes (borrelia burgdorferi sensu lato [s.l.]) in three state parks in sonoma county, california, usa, during 2003 and 2004. in total, 113 birds were collected, 50 (44.2%) of which were found to be infested by 361 ixodid ticks representing three species: the western black-legged tick (ixodes pacificus, n=248), the rabbit tick (haemaphysalis leporispalustris, n= ...	2006	17255442
bartonella quintana endocarditis in dogs.	we provide the first evidence that bartonella quintana can infect dogs and cause typical signs of endocarditis. using pcr and sequencing, we identified b. quintana in the blood of a dog from the united states with aortic valve endocarditis and probably also in the mitral valve of a dog from new zealand with endocarditis.	2006	17326937
outer surface protein b is critical for borrelia burgdorferi adherence and survival within ixodes ticks.	survival of borrelia burgdorferi in ticks and mammals is facilitated, at least in part, by the selective expression of lipoproteins. outer surface protein (osp) a participates in spirochete adherence to the tick gut. as ospb is expressed on a bicistronic operon with ospa, we have now investigated the role of ospb by generating an ospb-deficient b. burgdorferi and examining its phenotype throughout the spirochete life cycle. similar to wild-type isolates, the ospb-deficient b. burgdorferi were ab ...	2007	17352535
ability of transstadially infected ixodes pacificus (acari: ixodidae) to transmit west nile virus to song sparrows or western fence lizards.	the hypothesis that ixodes pacificus cooley & kohls (acari: ixodidae) may serve as a reservoir and vector of west nile virus (family flaviviridae, genus flavivirus, wnv) in california was tested by determining the ability of this tick species to become infected with the ny99 strain of wnv while feeding on viremic song sparrows, to maintain the infection transstadially, and then to transmit wnv to recipient naive song sparrows and western fence lizards during the nymphal stage. the percentage of ...	2007	17427704
ectoparasite diversity and exposure to vector-borne disease agents in wild rodents in central coastal california.	a survey of wild rodents was performed in the morro bay area of central coastal california to determine serological and polymerase chain reaction (pcr) prevalence of anaplasma phagocytophilum dumler, barbet, bekker, dasch, palmer, ray, rikihisa, and rurangirwa, borrelia burgdorferi johnson, schmidt, hyde, steigerwalt, and brenner, francisella tularensis mccoy, and yersinia pestis yersin; to describe the ectoparasitic fauna on important vector-borne disease hosts; and to determine whether pathoge ...	2007	17427705
analysis of the first australian strains of bartonella quintana reveals unique genotypes.	bartonella quintana is increasingly recognized as a cause of clinical disease in various geographical locations. we characterized three australian strains associated with endocarditis, using established molecular-typing techniques, the 16s/23s rrna intergenic spacer (its) region, and multispacer typing (mst). all strains examined demonstrated novel its and/or mst genotypes. further characterization of australian strains is required to determine whether there is an association between genotype an ...	2007	17428928
high-resolution genetic fingerprinting of european strains of anaplasma phagocytophilum by use of multilocus variable-number tandem-repeat analysis.	anaplasma phagocytophilum is a widely distributed tick-borne pathogen of humans, livestock, and companion animals. we used in silico methods to identify 10 variable-number tandem-repeat (vntr) loci within the genome sequence of the a. phagocytophilum hz strain and used these data to develop a multilocus vntr-based typing scheme for the species. having confirmed the stability of four of the loci in replicates of the a. phagocytophilum strain that had been subjected to different numbers of passage ...	2007	17442796
prevalence of anaplasma phagocytophilum in domestic felines in the united states.	anaplasma phagocytophilum is among the more common tick-borne disease agents in the united states. it is of veterinary and public health significance as dogs, cats, and human beings are known to be susceptible. a. phagocytophilum is transmitted trans-stadially by either nymphs or adults of either the black-legged tick (ixodes scapularis) or the western black-legged tick (ixodes pacificus). little information is available regarding either the prevalence of this agent in cats or the dynamics of ve ...	2007	17493756
purine salvage pathways among borrelia species.	genome sequencing projects on two relapsing fever spirochetes, borrelia hermsii and borrelia turicatae, revealed differences in genes involved in purine metabolism and salvage compared to those in the lyme disease spirochete borrelia burgdorferi. the relapsing fever spirochetes contained six open reading frames that are absent from the b. burgdorferi genome. these genes included those for hypoxanthine-guanine phosphoribosyltransferase (hpt), adenylosuccinate synthase (pura), adenylosuccinate lya ...	2007	17502392
gray foxes (urocyon cinereoargenteus) as a potential reservoir of a bartonella clarridgeiae-like bacterium and domestic dogs as part of a sentinel system for surveillance of zoonotic arthropod-borne pathogens in northern california.	two species of bartonella, a novel bartonella clarridgeiae-like bacterium and b. vinsonii subsp. berkhoffii, were isolated from rural dogs and gray foxes in northern california. a novel b. clarridgeiae-like species was isolated from 3 (1.7%) of 182 dogs and 22 (42%) of 53 gray foxes, while b. vinsonii subsp. berkhoffii was isolated from 1 dog (0.5%) and 5 gray foxes (9.4%). pcr and dna sequence analyses of the citrate synthase (glta) gene and the 16s-23s intergenic spacer region suggested that s ...	2007	17553970
analysis of the immune-related transcriptome of a lophotrochozoan model, the marine annelid platynereis dumerilii.	the marine annelid platynereis dumerilii (polychaeta, nereididae) has been recognized as a slow-evolving lophotrochozoan that attracts increasing attention as a valuable model for evolutionary and developmental research. here, we analyzed its immune-related transcriptome. for targeted identification of immune-induced genes we injected bacterial lipopolysaccharide, a commonly used elicitor of innate immune responses, and applied the suppression subtractive hybridization technique that selectively ...	2007	17617895
vertebrate hosts of ixodes pacificus (acari: ixodidae) in california.	the western black-legged tick, ixodes pacificus cooley & kohls, is an important parasite and vector of disease agents that affect human and animal health in the western united states. this paper presents a review of all published california host records for i. pacificus. unpublished data from public health, academic, and vector control agencies and researchers were reviewed as well. host species were identified for each active life stage (larvae, nymph and adult). a total of 108 vertebrate speci ...	2007	17633435
spatial and temporal variability of the glossina palpalis palpalis population in the mbini focus (equatorial guinea).	human african trypanosomiasis is a vector-borne parasitic disease. the geographical distribution of the disease is linked to the spatial distribution of the tsetse fly. as part of a control campaign using traps, the spatial and temporal variability is analysed of the glossina populations present in the mbini sleeping sickness foci (equatorial guinea).	2007	17760953
life cycles of seven ixodid tick species (acari: ixodidae) under standardized laboratory conditions.	studies of transmission, maintenance, infectivity, virulence, and pathogenicity of tick-borne agents require the use of large numbers of live laboratory-raised ticks. colonies of ixodes scapularis say, ixodes pacificus cooley & kohls, amblyomma americanum (l.), dermacentor occidentalis marx, dermacentor variabilis (say), hemaphysalis leporispalustris (packard), and rhipicephalus sanguineus (latrielle) have been maintained in our laboratory at the centers for disease control and prevention for fi ...	2007	17915502
divergent evolution of arrested development in the dauer stage of caenorhabditis elegans and the infective stage of heterodera glycines.	the soybean cyst nematode heterodera glycines is the most important parasite in soybean production worldwide. a comprehensive analysis of large-scale gene expression changes throughout the development of plant-parasitic nematodes has been lacking to date.	2007	17919324
survey for zoonotic rickettsial pathogens in northern flying squirrels, glaucomys sabrinus, in california.	epidemic typhus, caused by rickettsia prowazekii, is maintained in a southern flying squirrel (glaucomys volans) sylvatic cycle in the southeastern united states. the northern flying squirrel (glaucomys sabrinus) has not been previously associated with r. prowazekii transmission. a second rickettsial pathogen, anaplasma phagocytophilum, infects dusky-footed woodrats (neotoma fuscipes) and tree squirrels in northern california. because northern flying squirrels or their ectoparasites have not bee ...	2007	17984264
differential exposure to anaplasma phagocytophilum in rodent species in northern california.	anaplasma phagocytophilum is a zoonotic tick-borne rickettsial pathogen that causes granulocytic anaplasmosis (ga) in humans, horses, and dogs. in california, dusky-footed woodrats (neotoma fuscipes) are a putative reservoir host, and ixodes pacificus is a vector for transmission from rodents to humans, dogs, and horses. cases are clustered in coastal and sierra nevada foothill regions, but not necessarily in proximity to infected woodrats. this study was designed to compare exposures and active ...	2008	18047398
an insight into the sialome of the soft tick, ornithodorus parkeri.	while hard ticks (ixodidae) take several days to feed on their hosts, soft ticks (argasidae) feed faster, usually taking less than 1h per meal. saliva assists in the feeding process by providing a cocktail of anti-hemostatic, anti-inflammatory and immunomodullatory compounds. saliva of hard ticks has been shown to contain several families of genes each having multiple members, while those of soft ticks are relatively unexplored. analysis of the salivary transcriptome of the soft tick ornithodoru ...	2008	18070662
comparative sialomics between hard and soft ticks: implications for the evolution of blood-feeding behavior.	ticks evolved various mechanisms to modulate their host's hemostatic and immune defenses. differences in the anti-hemostatic repertoires suggest that hard and soft ticks evolved anti-hemostatic mechanisms independently, but raise questions on the conservation of salivary gland proteins in the ancestral tick lineage. to address this issue, the sialome (salivary gland secretory proteome) from the soft tick, argas monolakensis, was determined by proteomic analysis and cdna library construction of s ...	2008	18070664
immune system responses and fitness costs associated with consumption of bacteria in larvae of trichoplusia ni.	insects helped pioneer, and persist as model organisms for, the study of specific aspects of immunity. although they lack an adaptive immune system, insects possess an innate immune system that recognizes and destroys intruding microorganisms. its operation under natural conditions has not been well studied, as most studies have introduced microbes to laboratory-reared insects via artificial mechanical wounding. one of the most common routes of natural exposure and infection, however, is via foo ...	2007	18154650
lyme disease vaccine.		2000	18159278
variability and action mechanism of a family of anticomplement proteins in ixodes ricinus.	ticks are blood feeding arachnids that characteristically take a long blood meal. they must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. this is achieved by expressing batteries of salivary proteins coded by multigene families.	2008	18167559
distantly related lipocalins share two conserved clusters of hydrophobic residues: use in homology modeling.	lipocalins are widely distributed in nature and are found in bacteria, plants, arthropoda and vertebra. in hematophagous arthropods, they are implicated in the successful accomplishment of the blood meal, interfering with platelet aggregation, blood coagulation and inflammation and in the transmission of disease parasites such as trypanosoma cruzi and borrelia burgdorferi. the pairwise sequence identity is low among this family, often below 30%, despite a well conserved tertiary structure. under ...	2008	18190694
need for improved methods to collect and present spatial epidemiologic data for vectorborne diseases.	improved methods for collection and presentation of spatial epidemiologic data are needed for vectorborne diseases in the united states. lack of reliable data for probable pathogen exposure site has emerged as a major obstacle to the development of predictive spatial risk models. although plague case investigations can serve as a model for how to ideally generate needed information, this comprehensive approach is cost-prohibitive for more common and less severe diseases. new methods are urgently ...	2007	18258029
host-seeking behavior of ixodes pacificus (acari: ixodidae) nymphs in relation to environmental parameters in dense-woodland and woodland-grass habitats.	in the far-western united states, the bacteria that cause lyme disease (borrelia burgdorferi, bb) and human granulocytic anaplasmosis (anaplasma phagocytophilum, ap) are transmitted by the western black-legged tick (ixodes pacificus). in a dense woodland, human behaviors involving contact with wood were recently found to pose greater risk for encountering i. pacificus nymphs than behaviors entailing exclusive exposure to leaf litter. a four-year follow-up study was undertaken in the same woodlan ...	2007	18260527
isolation, cloning and structural characterisation of boophilin, a multifunctional kunitz-type proteinase inhibitor from the cattle tick.	inhibitors of coagulation factors from blood-feeding animals display a wide variety of structural motifs and inhibition mechanisms. we have isolated a novel inhibitor from the cattle tick boophilus microplus, one of the most widespread parasites of farm animals. the inhibitor, which we have termed boophilin, has been cloned and overexpressed in escherichia coli. mature boophilin is composed of two canonical kunitz-type domains, and inhibits not only the major procoagulant enzyme, thrombin, but i ...	2008	18286181
climate change and infectious diseases in north america: the road ahead.	global climate change is inevitable--the combustion of fossil fuels has resulted in a buildup of greenhouse gases within the atmosphere, causing unprecedented changes to the earth's climate. the fourth assessment report of the intergovernmental panel on climate change suggests that north america will experience marked changes in weather patterns in coming decades, including warmer temperatures and increased rainfall, summertime droughts and extreme weather events (e.g., tornadoes and hurricanes) ...	0	18332386
a possible canine tick-bite reaction to ixodes muris.	an airedale terrier became acutely ill following attachment of an ixodes muris tick. clinical signs waned within hours of tick removal, similar to a pattern previously documented in animals harboring i. muris. this supports the theory that i. muris can induce a noninfectious, severe inflammatory reaction in domestic animals.	2008	18390101
lyme disease in oregon.	the incidence of lyme disease in oregon is calculated from cases reported to the oregon state health division. we reviewed the exposure history of reported cases of lyme disease and performed field surveys for infected ixodes pacificus ticks. the incidence of lyme disease correlated with the distribution of infected i. pacificus ticks.	2008	18448697
diagnosis and treatment of lyme disease.	lyme disease is the most common tick-borne disease in the united states. this review details the risk factors, clinical presentation, treatment, and prophylaxis for the disease. information was obtained from a search of the pubmed and medline databases (keyword: lyme disease) for articles published from august 31, 1997, through september 1, 2007. approximately 20,000 cases of lyme disease are reported annually. residents of the coastal northeast, northwest california, and the great lakes region ...	2008	18452688
biology of infection with borrelia burgdorferi.	the spirochete borrelia burgdorferi is a tick-borne obligate parasite whose normal reservoir is a variety of small mammals. although infection of these natural hosts does not lead to disease, infection of humans can result in lyme disease as a consequence of the human immunopathologic response to b burgdorferi. consistent with the pathogenesis of lyme disease, bacterial products that allow b burgdorferi to replicate and survive seem to be primarily what is required for the bacterium to cause dis ...	2008	18452798
molecular detection of bartonella schoenbuchensis from ectoparasites of deer in massachusetts.	deer keds (lipoptena cervi) are thought to have been introduced into new england from europe during the 1800 s. we sought to determine whether l. cervi from massachusetts deer contained evidence of infection by bartonella schoenbuchensis, which appears to be maintained by l. cervi in europe. five of 6 keds were found to contain b. schoenbuchensis dna, and 2 deer ticks cofeeding on deer with such keds did as well. the detection of bartonella dna in deer ticks probably represents contamination by ...	2008	18454595
insight into the sialome of the castor bean tick, ixodes ricinus.	in recent years, there have been several sialome projects revealing transcripts expressed in the salivary glands of ticks, which are important vectors of several human diseases. here, we focused on the sialome of the european vector of lyme disease, ixodes ricinus.	2008	18489795
risk maps for range expansion of the lyme disease vector, ixodes scapularis, in canada now and with climate change.	lyme disease is the commonest vector-borne zoonosis in the temperate world, and an emerging infectious disease in canada due to expansion of the geographic range of the tick vector ixodes scapularis. studies suggest that climate change will accelerate lyme disease emergence by enhancing climatic suitability for i. scapularis. risk maps will help to meet the public health challenge of lyme disease by allowing targeting of surveillance and intervention activities.	2008	18498647
the diversity of reproductive parasites among arthropods: wolbachia do not walk alone.	inherited bacteria have come to be recognised as important components of arthropod biology. in addition to mutualistic symbioses, a range of other inherited bacteria are known to act either as reproductive parasites or as secondary symbionts. whilst the incidence of the alpha-proteobacterium wolbachia is relatively well established, the current knowledge of other inherited bacteria is much weaker. here, we tested 136 arthropod species for a range of inherited bacteria known to demonstrate reprod ...	2008	18577218
transmission of bartonella henselae by ixodes ricinus.	bartonella spp. are facultative intracellular bacteria associated with several emerging diseases in humans and animals. b. henselae causes cat-scratch disease and is increasingly associated with several other syndromes, particularly ocular infections and endocarditis. cats are the main reservoir for b. henselae and the bacteria are transmitted to cats by cat fleas. however, new potential vectors are suspected of transmitting b. henselae, in particular, ixodes ricinus, the most abundant ixodid ti ...	2008	18598628
evidence of the role of tick subolesin in gene expression.	subolesin is an evolutionary conserved protein that was discovered recently in ixodes scapularis as a tick protective antigen and has a role in tick blood digestion, reproduction and development. in other organisms, subolesin orthologs may be involved in the control of developmental processes. because of the profound effect of subolesin knockdown in ticks and other organisms, we hypothesized that subolesin plays a role in gene expression, and therefore affects multiple cellular processes. the ob ...	2008	18673577
evaluation of squirrels (rodentia: sciuridae) as ecologically significant hosts for anaplasma phagocytophilum in california.	granulocytic anaplasmosis (ga), caused by anaplasma phagocytophilum, is a potentially fatal, emerging rickettsial disease of humans, domestic animals, and wildlife. the purpose of this study was to determine whether sciurids from multiple areas of northern california were infested with ticks or exposed to or infected with a. phagocytophilum using polymerase chain reaction (pcr) and indirect-fluorescent antibody (ifa) serology. sciurids of nine different tree- and ground-dwelling species were ass ...	2008	18714881
an insight into the salivary transcriptome and proteome of the soft tick and vector of epizootic bovine abortion, ornithodoros coriaceus.	the salivary glands of blood-sucking arthropods contain a redundant 'magic potion' that counteracts their vertebrate host's hemostasis, inflammation, and immunity. we here describe the salivary transcriptome and proteomics (sialome) of the soft tick ornithodoros coriaceus. the resulting analysis helps to consolidate the classification of common proteins found in both soft and hard ticks, such as the lipocalins, kunitz, cystatin, basic tail, hebraein, defensin, til domain, metalloprotease, 5'-nuc ...	2008	18725333
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 ...	2009	18762211
functional characterization and novel rickettsiostatic effects of a kunitz-type serine protease inhibitor from the tick dermacentor variabilis.	here we report the novel bacteriostatic function of a five-domain kunitz-type serine protease inhibitor (kpi) from the tick dermacentor variabilis. as ticks feed, they release anticoagulants, anti-inflammatory and immunosuppressive molecules that mediate the formation of the feeding lesion on the mammalian host. a number of kpis have been isolated and characterized from tick salivary gland extracts. interestingly, we observe little d. variabilis kpi gene expression in the salivary gland and abun ...	2008	18779339
spatial dynamics of lyme disease: a review.	lyme disease (ld), the most frequently reported vector-borne disease in the united states, requires that humans, infected vector ticks, and infected hosts all occur in close spatial proximity. understanding the spatial dynamics of ld requires an understanding of the spatial determinants of each of these organisms. we review the literature on spatial patterns and environmental correlates of human cases of ld and the vector ticks, ixodes scapularis in the northeastern and midwestern united states ...	2008	18787920
relative importance of ixodes ricinus and ixodes trianguliceps as vectors for anaplasma phagocytophilum and babesia microti in field vole (microtus agrestis) populations.	the importance of ixodes ricinus in the transmission of tick-borne pathogens is well recognized in the united kingdom and across europe. however, the role of coexisting ixodes species, such as the widely distributed species ixodes trianguliceps, as alternative vectors for these pathogens has received little attention. this study aimed to assess the relative importance of i. ricinus and i. trianguliceps in the transmission of anaplasma phagocytophilum and babesia microti among united kingdom fiel ...	2008	18820068
identifying the reservoir hosts of the lyme disease spirochete borrelia burgdorferi in california: the role of the western gray squirrel (sciurus griseus).	we investigated the role of the western gray squirrel (sciurus griseus) as a reservoir host of the lyme disease spirochete borrelia burgdorferi. a survey of 222 western gray squirrels in california showed an overall prevalence of b. burgdorferi infection of 30%, although at a county level, prevalence of infection ranged from 0% to 50% by polymerase chain reaction. laboratory trials with wild-caught western gray squirrels indicated that squirrels were competent reservoir hosts of the lyme disease ...	2008	18840740
lyme disease: a zoonotic disease of increasing importance to canadians.		2008	18854461
the laboratory diagnosis of lyme borreliosis: guidelines from the canadian public health laboratory network.	lyme borreliosis is uncommonly seen in canada. most cases have occurred in close proximity to small geographical areas where infected ticks have become established. although few cases are seen, thousands of patients are tested yearly. unless patients are carefully selected and an appropriately sensitive and specific testing algorithm is applied, large numbers of patients without lyme borreliosis will be incorrectly diagnosed. the canadian public health laboratory network has developed the presen ...	2007	18923770
evaluation of the recombinant vlse-based liaison chemiluminescence immunoassay for detection of borrelia burgdorferi and diagnosis of lyme disease.	recent efforts to improve the serologic diagnosis of lyme disease have included the use of a synthetic peptide (c6) that reproduces the sequence of invariable region 6 of vlse, the variable surface antigen of borrelia burgdorferi. in the present study, the diagnostic performance of diasorin's recombinant vlse-based chemiluminescence immunoassay in 1,947 human serum samples was evaluated. sensitivity was determined using two serum panels from the cdc. for panel i, we observed sensitivities of 68. ...	2008	18945880
effect of climate change on lyme disease risk in north america.	an understanding of the influence of climate change on ixodes scapularis, the main vector of lyme disease in north america, is a fundamental component in assessing changes in the spatial distribution of human risk for the disease. we used a climate suitability model of i. scapularis to examine the potential effects of global climate change on future lyme disease risk in north america. a climate-based logistic model was first used to explain the current distribution of i. scapularis in north amer ...	2005	19008966
exploring the mialome of ticks: an annotated catalogue of midgut transcripts from the hard tick, dermacentor variabilis (acari: ixodidae).	ticks are obligate blood feeders. the midgut is the first major region of the body where blood and microbes ingested with the blood meal come in contact with the tick's internal tissues. little is known about protein expression in the digestive tract of ticks. in this study, for analysis of global gene expression during tick attachment and feeding, we generated and sequenced 1,679 random transcripts (ests) from cdna libraries from the midguts of female ticks at varying stages of feeding.	2008	19021911
ixodes ricinus tick lipocalins: identification, cloning, phylogenetic analysis and biochemical characterization.	during their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. among these proteins, lipocalins play a major role in the modulation of the inflammatory response.	2008	19096708
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
feeding preferences of the immature stages of three western north american ixodid ticks (acari) for avian, reptilian, or rodent hosts.	larval and nymphal ixodes pacificus cooley and kohls, i. (ixodes) jellisoni cooley and kohls, and dermacentor occidentalis marx were tested for host preference when simultaneously presented with a deer mouse (peromyscus maniculatus wagner), california kangaroo rat (dipodomys californicus merriam), western fence lizard (sceloporus occidentalis baird and girard), and california towhee (pipilo crissalis vigors) in an experimental apparatus. differences were observed in the preferences among the thr ...	2009	19198525
rrp1, a cyclic-di-gmp-producing response regulator, is an important regulator of borrelia burgdorferi core cellular functions.	two-component systems (tcs) are universal among bacteria and play critical roles in gene regulation. our understanding of the contributions of tcs in the biology of the borrelia is just now beginning to develop. borrelia burgdorferi, a causative agent of lyme disease, harbours a tcs comprised of open reading frames (orfs) bb0419 and bb0420. bb0419 encodes a response regulator designated rrp1, and bb0420 encodes a hybrid histidine kinase-response regulator designated hpk1. rrp1, which contains a ...	2009	19210621
reptile infection with anaplasma phagocytophilum, the causative agent of granulocytic anaplasmosis.	granulocytic anaplasmosis (ga) is a potentially fatal tick-borne rickettsial disease that occurs sporadically in the far western united states. we evaluated the prevalence of anaplasma phagocytophilum in multiple species of lizards and snakes from enzootic sites in northern california, described the infestation prevalence of its tick vector ixodes pacificus on reptiles, and conducted an experimental challenge of western fence lizards (sceloporus occidentalis) and pacific gopher snakes (pituophis ...	2009	19281295
reservoir competence of the redwood chipmunk (tamias ochrogenys) for anaplasma phagocytophilum.	granulocytic anaplasmosis (ga) is an emerging tick-transmitted disease that persists in rodent- ixodes ricinus-complex tick cycles across the holarctic. although the putative reservoir for anaplasmosis in the western united states is the dusky-footed woodrat (neotoma fuscipes), this rodent was not shown reservoir-competent because of failure of infection from woodrats to other animals via ticks. redwood chipmunks are common in habitats where anaplasma phagocytophilum is common, have high pcr- an ...	2009	19327022
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
ecology of anaplasma phagocytophilum infection in gray foxes (urocyon cinereoargenteus) in northwestern california.	although granulocytic anaplasmosis, caused by infection of anaplasma phagocytophilum, is an emerging human and domestic animal disease, the ecology and natural history of the parasite is not well understood. gray foxes (urocyon cinereoargenteus) are relatively common, occasionally peri-urban mesocarnivores whose geographic distribution overlaps the reported distribution of granulocytic anaplasmosis in humans and domestic animals in north america. we evaluated the potential of foxes as hosts and ...	2009	19395744
distinct ecologically relevant strains of anaplasma phagocytophilum.		2009	19402993
wild canids as sentinels of ecological health: a conservation medicine perspective.	abstract : the extinction of species across the globe is accelerating, directly or indirectly due to human activities. biological impoverishment, habitat fragmentation, climate change, increasing toxification, and the rapid global movement of people and other living organisms have worked synergistically to diminish ecosystem function. this has resulted in unprecedented levels of disease emergence, driven by human-induced environmental degradation, which poses a threat to the survival and health ...	2009	19426446
lyme disease in canada: q & a for paediatricians.		2009	19436561
meningitis due to a "bartonella washoensis"-like human pathogen.	we report the second human case of infection caused by an organism identified as the proposed bartonella species, "b. washoensis." the organism was isolated from a blood sample from a patient presenting with meningitis and early sepsis. oropsylla montana fleas were implicated as the vector for disease transmission in this case.	2009	19439538
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
the emergence of lyme disease in canada.		2009	19506281
inclusion bodies in tick-borne diseases diagnosed in patients from northern wisconsin.		0	19574488
comprehensive seroprofiling of sixteen b. burgdorferi ospc: implications for lyme disease diagnostics design.	early diagnosis of lyme disease (ld) is critical to successful treatment. however, current serodiagnostic tests do not reliably detect antibodies during early infection. ospc induces a potent early immune response and is also one of the most diverse proteins in the borrelia proteome. yet, at least 70% of the amino acid sequence is conserved among all 21 known ospc types. we performed a series of comprehensive seroprofiling studies to select the ospc types that have the most cross-reactive immuno ...	2009	19576856
current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and ehrlichia ewingii ehrlichiosis.	anaplasma phagocytophilum, ehrlichia chaffeensis and ehrlichia ewingii are emerging tick-borne pathogens and are the causative agents of human granulocytic anaplasmosis, human monocytic ehrlichiosis and e. ewingii ehrlichiosis, respectively. collectively, these are referred to as human ehrlichioses. these obligate intracellular bacterial pathogens of the family anaplasmataceae are transmitted by ixodes spp. or amblyomma americanum ticks and infect peripherally circulating leukocytes to cause inf ...	2009	19681699
effect of prescribed fire for tick control in california chaparral.	prescribed fire was investigated as a method for controlling ixodid and argasid ticks in chaparral habitats in northern california. two experimental and two adjacent control plots within a wildlife preserve were monitored for 1 yr postburn. ticks were collected by flagging vegetation, by co2-baited pitfall trap, and by live-trapping rodents. twice as many rodents were caught at control sites compared with burn sites and no dusky-footed woodrats, neotoma fuscipes baird, were found in the treatmen ...	2009	19769046
population structure of the lyme borreliosis spirochete borrelia burgdorferi in the western black-legged tick (ixodes pacificus) in northern california.	factors potentially contributing to the lower incidence of lyme borreliosis (lb) in the far-western than in the northeastern united states include tick host-seeking behavior resulting in fewer human tick encounters, lower densities of borrelia burgdorferi-infected vector ticks in peridomestic environments, and genetic variation among b. burgdorferi spirochetes to which humans are exposed. we determined the population structure of b. burgdorferi in over 200 infected nymphs of the primary bridging ...	2009	19783741
destruction of spirochete borrelia burgdorferi round-body propagules (rbs) by the antibiotic tigecycline.	persistence of tissue spirochetes of borrelia burgdorferi as helices and round bodies (rbs) explains many erythema-lyme disease symptoms. spirochete rbs (reproductive propagules also called coccoid bodies, globular bodies, spherical bodies, granules, cysts, l-forms, sphaeroplasts, or vesicles) are induced by environmental conditions unfavorable for growth. viable, they grow, move and reversibly convert into motile helices. reversible pleiomorphy was recorded in at least six spirochete genera (>1 ...	2009	19843691
delineation of a new species of the borrelia burgdorferi sensu lato complex, borrelia americana sp. nov.	analysis of borrelia isolates collected from ticks, birds, and rodents from the southeastern united states revealed the presence of well-established populations of borrelia burgdorferi sensu stricto, borrelia bissettii, borrelia carolinensis, and borrelia sp. nov. multilocus sequence analysis of five genomic loci from seven samples representing borrelia sp. nov. isolated from nymphal ixodes minor collected in south carolina showed their close relatedness to california strains known as genomospec ...	2009	19846628
granulocytic anaplasmosis in three dogs from saskatoon, saskatchewan.	three dogs from saskatoon, saskatchewan were diagnosed with acute granulocytic anaplasmosis. fever, lethargy, inappetence, vomiting, diarrhea, and lameness were reported. lymphopenia, thrombocytopenia, and splenomegaly were identified in all dogs. inclusions were identified within the cytoplasm of blood neutrophils, and infection with anaplasma phagocytophilum was confirmed by polymerase chain reaction.	2009	19881921
[morphofunctional changes in the midgut of ticks of the genus ixodes (acarina: ixodidae) during life cycle].	morphofunctional investigations of five ixodes species (ixodes pacificus, i. pavlovsky, i. persulcatus, i. ricinus and i. scapularis) were carried out. it was established, that the change of midgut epithelium lags at the each next developmental stage, and it is not synchronized with general processes of metamorphosis and organogenesis during molts. the midgut epithelium of a previous phase of the life cycle persists and functions during the feeding stage at the next phase.	2009	19957908
molecular identification of salp15, a key salivary gland protein in the transmission of lyme disease spirochetes, from ixodes persulcatus and ixodes pacificus (acari: ixodidae).	salp15 is a multifunctional protein, vital to the tick in its need to obtain vertebrate host blood without stimulating a host inflammatory and immune response. the salpl5 protein from both ixodes scapularis say and ixodes ricinus (l.), the principal vectors of the lyme disease spirochete in eastern north america and europe, respectively, have been well characterized and found to bind the murine cd4 receptor, dc-sign, and the ospc protein of borrelia burgdorferi. in the current study, we characte ...	2009	19960697
niche partitioning of borrelia burgdorferi and borrelia miyamotoi in the same tick vector and mammalian reservoir species.	the lyme borreliosis agent borrelia burgdorferi and the relapsing fever group species borrelia miyamotoi co-occur in the united states. we used species-specific, quantitative polymerase chain reaction to study both species in the blood and skin of peromyscus leucopus mice and host-seeking ixodes scapularis nymphs at a connecticut site. bacteremias with b. burgdorferi or b. miyamotoi were most prevalent during periods of greatest activity for nymphs or larvae, respectively. whereas b. burgdorferi ...	2009	19996447
distribution of the lyme disease spirochete borrelia burgdorferi in naturally and experimentally infected western gray squirrels (sciurus griseus).	the dynamics of borrelia burgdorferi infections within its natural hosts are poorly understood. we necropsied four wild-caught western gray squirrels (sciurus griseus) that were acquired during a previous study that evaluated the reservoir competence of this rodent for the lyme disease spirochete. one animal was infected experimentally, whereas the others were infected in the wild before capture. to investigate dissemination of b. burgdorferi and concurrent histopathologic lesions in different t ...	2010	20017717
larval keys to the genera of ixodidae (acari) and species of ixodes (latreille) ticks established in california.	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 ...	2008	20027236
molecular and clinical evidence of ehrlichia chaffeensis infection in cameroonian patients with undifferentiated febrile illness.	in the u.s.a., human monocytotropic ehrlichiosis (hme) caused by ehrlichia chaffeensis is an emerging tick-transmitted zoonosis. in cameroon, where e. canis, e. chaffeensis and e. ewingii have recently been detected in dogs and/or ticks (rhipicephalus sanguineus), the potential exists for human infections. patients from the coastal region of cameroon who had acute fevers of unknown aetiology were therefore checked for ehrlichial infection, using a real-time pcr that amplifies part of a genus-spe ...	2009	20030996
platelet aggregation inhibitors from hematophagous animals.	salivary glands from blood-sucking animals (e.g., mosquitoes, bugs, sand flies, fleas, ticks, leeches, hookworms, bats) are a rich source of bioactive molecules that counteract hemostasis in a redundant and synergistic manner. this review discusses recent progress in the identification of salivary inhibitors of platelet aggregation, their molecular characterization, and detailed mechanism of action. diversity of inhibitors is remarkable, with distinct families of proteins characterized as apyras ...	2009	20035779
prevalence of bartonella henselae and borrelia burgdorferi sensu lato dna in ixodes ricinus ticks in europe.	bartonella spp. can cause persistent bloodstream infections in humans and animals. to determine whether bartonella henselae is present in questing ixodes ricinus ticks, we analyzed the prevalence of b. henselae dna among tick stages compared to the prevalence of dna from borrelia burgdorferi sensu lato, the pathogen most frequently transmitted by ticks. b. henselae dna was present with a prevalence of up to approximately 40% in tick populations sampled in four european sites (eberdingen, germany ...	2010	20061459
[ehrlichiosis/anaplasmosis].	ehrlichiosis and anaplasmosis are zoonoses caused by bacteria from the family anaplasmataceae, including human and animal pathogens. the human pathogens are ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (hme), anaplasma phagocytophilum, the pathogen causing human granulocytic anaplasmosis (hga), e. ewingii and neorickettsia sennetsu, granulocytotropic and monocytotropic ehrlichia species, respectively. ehrlichia spp. are small, gram-negative, obligate intracellular b ...	2009	20077398
coinfection of western gray squirrel (sciurus griseus) and other sciurid rodents with borrelia burgdorferi sensu stricto and anaplasma phagocytophilum in california.	overlapping geographic distributions of tick-borne disease agents utilizing the same tick vectors are common, and coinfection of humans, domestic animals, wildlife, and ticks with both borrelia burgdorferi and anaplasma phagocytophilum has been frequently reported. this study was undertaken in order to evaluate the prevalence of both b. burgdorferi sensu stricto (hereinafter referred to as b. burgdorferi) and a. phagocytophilum in several species of sciurid rodents from northern california, usa. ...	2010	20090047
lyme disease vaccine.		2000	20177519