Publications

cases of lyme disease in the united states: locations correlated with distribution of ixodes dammini.	lyme disease, defined by erythema chronicum migrans and sometimes followed by neurologic, cardiac, or joint involvement, is known to have affected 512 patients in the united states. the disease seems to occur in three distinct foci: along the northeastern coast, in wisconsin, and in california and oregon, a distribution that correlates closely with that of ixodes dammini in the first two areas and with ixodes pacificus in the last. the implicated tick, saved by six patients in the northeast, was ...	1979	496106
lyme disease: additional evidence of widespread distribution. recognition of a tick-borne dermatitis-encephalitis-arthritis syndrome in an area of known ixodes tick distribution.	lyme disease is a process of unknown etiology that has been linked to bites of ticks of the ixodes ricinus complex. central minnesota is an area of known ixodes dammini distribution. this case represents the first recognition of lyme disease from this area. this case presented as a fluctuating meningoencephalitis with superimposed cranial neuropathy. the characteristic skin lesion, erythema chronicum migrans, was recognized by history, and oligoarticular arthritis subsequently developed. physici ...	1982	7072749
lyme disease in northern california.	lyme disease is a recently described clinical entity with cutaneous, neurologic, articular and cardiac manifestations. since the original description of the disease in 1977, more than 500 cases have been reported. although the vast majority of patients have been from the area near lyme, connecticut, we have seen four patients from northern california with various aspects of lyme disease. this diagnosis should be considered in patients who have traveled to tick regions and who have a distinctive ...	1983	6636745
the global distribution of lyme disease.	erythema chronicum migrans (ecm), the skin lesion characteristic of lyme disease, was first described in sweden in 1909; subsequently, cases of ecm have been reported from at least 19 countries on three continents. in europe cases have occurred within the range of ixodes ricinus ticks, the recognized vector of ecm in europe, although one case outside this range has been ascribed to mosquito bites. in 1970 the first case of ecm acquired in the united states was reported, and in 1977, the full sym ...	1985	3885366
the western black-legged tick, ixodes pacificus: a vector of borrelia burgdorferi.	to determine the significance of the western black-legged tick, ixodes pacificus, as a vector of the lyme disease spirochete, borrelia burgdorferi, a tick/spirochete survey was conducted in northern california and southwestern oregon from 1982 to 1984. of 1,687 adult ticks collected off vegetation, 25 (1.48%) contained spirochetes. of 715 ticks from oregon, 14 (1.96%) were infected whereas 11 (1.13%) of 972 ticks from california harbored spirochetes. an isolate of 1 of the spirochetes reacted sp ...	1985	3898886
potential role of native and exotic deer and their associated ticks (acari: ixodidae) in the ecology of lyme disease in california, usa.	the relationship of native columbian black-tailed deer, two species of exotic deer (axis and fallow), and their ticks to the lyme disease spirochete, borrelia burgdorferi, was studied in coastal and inland areas of northern california, usa. spirochetemias were detected in 27% of black-tailed deer, 50% of axis deer, and 56% of fallow deer collected in late fall and winter. antibody prevalence was 38% in black-tailed deer, 24% in fallow deer, and 6% in axis deer. one to 3 tick species were collect ...	1986	3554845
acrodermatitis chronica atrophicans with antecedent lyme disease in a california. case report.		1986	3577485
clinical and serologic studies of canine borreliosis.	during 1984 and 1985, blood samples were obtained from 271 dogs that were suspected of having borreliosis. the dogs lived in areas known to be infested with ticks and had been examined because of limb/joint disorders or for unknown illnesses marked by fever, anorexia, or fatigue. lameness had been the most frequently reported clinical manifestation. analyses of serum specimens, by an indirect fluorescent antibody (ifa) method or by an elisa, detected antibodies to borrelia burgdorferi, the etiol ...	1987	3319989
characterization of borrelia burgdorferi strains isolated from ixodes pacificus ticks in california.	in a survey of 1,714 adult ixodes pacificus ticks collected in northern california, 24 (1.4%) were found to be infected with spirochetes that reacted with an anti-borrelia burgdorferi polyvalent conjugate in direct immunofluorescence tests. eleven isolates of b. burgdorferi from these ticks were characterized by monoclonal antibody, polyacrylamide gel electrophoresis, and western blot (immunoblot) analyses. ten of the isolates had molecular and antigenic characteristics similar to those of other ...	1987	3323225
lyme borreliosis in california. acarological, clinical, and epidemiological studies.	the relative abundance of, and spirochetal-infection rates in, adult ixodid ticks from eight lyme borreliosis clinical-case areas and two comparison areas were investigated in northern california from late fall to early spring, 1984-87. the western black-legged tick (ixodes pacificus) was the most abundant species at seven of nine sites yielding specimens as determined with a tick drag method. the pacific coast tick (dermacentor occidentalis) was the most abundant species at two sites, and lesse ...	1988	3263826
spirochetes in mammals and ticks (acari: ixodidae) from a focus of lyme borreliosis in california.	in northern california, antibodies to borrelia burgdorferi were detected in 58 of 73 (79%), and spirochetemias in one of 26 (4%) black-tailed jackrabbits (lepus californicus californicus), by indirect and direct immunofluorescence, respectively. five species of ticks (dermacentor occidentalis, d. parumapertus, ixodes neotomae, i. pacificus, and haemaphysalis leporispalustris) were collected from rabbits. two of these species of ticks were found to contain spirochetes; two of 10 (20%) i. neotomae ...	1988	3280837
antigenic characteristics of borrelia burgdorferi isolates from ixodid ticks in california.	twenty (1.4%) of 1,421 adult ixodes pacificus ticks and 2 (20%) of 10 adult ixodes neotomae ticks collected in five counties of northern california were found to contain spirochetes by direct immunofluorescence examination of their tissues with a polyvalent conjugate. borreliae isolated from the tissues of nine of these ticks (i. pacificus, 8; i. neotomae, 1) were identified as borrelia burgdorferi with specific monoclonal antibodies and characterized further by polyacrylamide gel electrophoresi ...	1989	2685030
lagomorphs as sentinels for surveillance of borreliosis in the far western united states.	brush rabbits (sylvilagus bachmani) and black-tailed jackrabbits (lepus californicus) from california (usa) were assayed for antibodies to borrelia burgdorferi, the etiologic agent of lyme borreliosis. significant antibody titers were detected in 90% (range, 67 to 100%) of brush rabbits from four of six localities, and in 90% of jackrabbits from a single locality, in northern california. one of the populations of brush rabbits that did not yield seropositive individuals inhabited an oceanic isla ...	1989	2716099
lyme disease in california: interrelationship of ixodes pacificus (acari: ixodidae), the western fence lizard (sceloporus occidentalis), and borrelia burgdorferi.	the relationship of immature western black-legged ticks, ixodes pacificus cooley and kohls, to the western fence lizard, sceloporus occidentalis baird and girard, and to the lyme disease spirochete, borrelia burgdorferi, was investigated in chaparral and woodland-grass habitats in northern california from 1984 to 1986. immature ticks were found on lizards in spring and summer, but the prevalence and abundance of ticks on this host were considerably greater in spring. the peak of larval abundance ...	1989	2769705
lyme disease in northern california.		1989	2773475
lyme carditis. severe conduction disorder.	lyme disease in most cases occurs in the states of connecticut, wisconsin, oregon, california, missouri and parts of the northeastern coast. showing the exception to the rule, the authors discuss a case in which a patient acquired the disease on the eastern shore of virginia.	1990	2304446
interlaboratory and intralaboratory comparisons of indirect immunofluorescence assays for serodiagnosis of lyme disease.	a conventional indirect immunofluorescence assay (ifa) and an anticomplement indirect immunofluorescence assay (acif) for detecting serum antibodies to borrelia burgdorferi in humans were evaluated during a prevalence survey in northern california. sera obtained from 119 current or former residents of an area in which lyme disease is endemic were split and tested by the ifa in two laboratories and the acif in a third. the seropositivity rate ranged from 15 to 20% with 88 to 93% agreement among l ...	1990	2203813
survey of birds and lizards for ixodid ticks (acari) and spirochetal infection in northern california.	a total of 138 birds (24 species) was captured in an oak woodland between december 1988 and june 1989 at the university of california, sierra foothill range field station, yuba county, calif. ticks were not found on 71 birds captured between december 1988 and march 1989. five subadult ixodes pacificus cooley & kohls were removed from 3 of 67 birds caught between april and june 1989. these three birds, an orange-crowned warbler (vermivora celata (say], a lazuli bunting (passerina amoena (say], an ...	1990	2280384
dna and protein analyses of tick-derived isolates of borrelia burgdorferi from california.	nine isolates of borrelia burgdorferi from ixodid ticks collected in northern california were characterized. restriction endonuclease analysis, pulsed-field gel electrophoresis, and western blot (immunoblot) analysis were used in this study. four isolates were very similar to each other. the others shared some similarities but were classified as having unique genotypes. a strain from an ixodes neotomae tick displayed the greatest genetic and antigenic diversity when compared to the isolates coll ...	1990	2332468
wood rats and kangaroo rats: potential reservoirs of the lyme disease spirochete in california.	the etiologic agent of lyme disease, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was isolated repeatedly from dusky-footed wood rats, neotoma fuscipes baird, and california kangaroo rats, dipodomys californicus merriam, in northern california. all animals were collected in a region endemic for lyme disease but for which the natural reservoir of b. burgdorferi was unknown. similar attempts to isolate spirochetes from lizards, other species of rodents, jack rabbits, and deer ...	1991	1875357
lyme disease in california: interrelationship of ixodid ticks (acari), rodents, and borrelia burgdorferi.	the association of immature ixodid ticks, several species of rodents, and the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was studied in two habitats in northern california in spring and summer 1985 and year-round in 1986. a total of 428 rodents were collected from ecotonal chaparral and a woodland-grass-rock outcrop; the former habitat yielded six species, the latter three species. the deer mouse, peromyscus maniculatus (wagner), and the piñon mou ...	1991	1941942
lyme disease surveillance in california.		1991	1848737
isolation of borrelia burgdorferi from ticks in southern california.		1992	1462548
risk factors for lyme disease in a small rural community in northern california.	a 1-year prospective study of risk factors for seropositivity to and contraction of lyme disease among members of a small rural community (population, approximately 150) was conducted in northwestern california in 1988-1989. the initial rate of seropositivity for borrelia burgdorferi for 119 current or former residents ranged from 15 to 20% among three laboratories, with statistically significant interlaboratory agreement. questionnaires were completed by 93 current residents at entry and 80 res ...	1992	1488962
the western fence lizard sceloporus occidentalis: evidence of field exposure to borrelia burgdorferi in relation to infestation by ixodes pacificus (acari: ixodidae).	the role of the western fence lizard sceloporus occidentalis in the enzootiology of the lyme disease spirochete borrelia burgdorferi was evaluated in the hopland and ukiah areas of mendocino county, california. in 1989, half of 74 lizards collected monthly from april to october at hopland were infested by the immature western black-legged tick ixodes pacificus at a mean intensity of 6.0 ticks per lizard. the prevalence of infestation of lizards by immature i. pacificus (36 of 73) at ukiah was si ...	1992	1524146
lyme disease in california: a novel enzootic transmission cycle of borrelia burgdorferi.	knowledge of zoonotic transmission cycles is essential for the development of effective strategies for disease prevention. the enzootiology of lyme disease in california differs fundamentally from that reported from the eastern united states. woodrats, not mice, serve as reservoir hosts, and ixodes neotomae, a nonhuman-biting tick, maintains the agent of lyme disease, borrelia burgdorferi, in enzootic cycles. the western black-legged tick, ixodes pacificus, is the primary vector to humans, but i ...	1992	1604318
first isolation of borrelia burgdorferi in southern california.	the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was isolated from the blood of a dusky-footed wood rat, neotoma fuscipes baird, in the san bernardino mountains of southern california. antigenic, protein, and molecular analyses demonstrated that the isolate varied slightly from most isolates of b. burgdorferi from northern california and was clearly distinct from other species of borrelia that are endemic to the state. this is the first reported iso ...	1992	1625299
nervous about ticks--assessing lyme disease risk in san diego county.		1992	1734618
distribution and molecular analysis of lyme disease spirochetes, borrelia burgdorferi, isolated from ticks throughout california.	previous studies describing the occurrence and molecular characteristics of lyme disease spirochetes, borrelia burgdorferi, from california have been restricted primarily to isolates obtained from the north coastal region of this large and ecologically diverse state. our objective was to look for and examine b. burdorferi organisms isolated from ixodes pacificus ticks collected from numerous regions spanning most parts of california where this tick is found. thirty-one isolates of b. burgdorferi ...	1993	8308101
isolation of borrelia burgdorferi from the blood of a bushy-tailed wood rat in california.	borrelia burgdorferi was isolated from the blood of a bushy-tailed wood rat (neotoma cinerea) from northeastern california, usa. this is the first isolation of live b. burgdorferi spirochetes from a wild animal in california. spirochetes were observed in stained tissues from the brain, liver, spleen, and kidneys.	1993	8355352
temporal and spatial distribution of ixodes pacificus and dermacentor occidentalis (acari: ixodidae) and prevalence of borrelia burgdorferi in contra costa county, california.	the seasonal activity and spatial distribution of adult and immature ixodes pacificus cooley & kohls and dermacentor occidentalis marx were determined along trails and on hillsides in two parks in contra costa county, ca. i. pacificus and d. occidentalis adults were most numerous in january and may, respectively. adult ticks were significantly more abundant along heavily vegetated trails than on open grassy hillsides, and on the uphill versus the downhill side of trails. five species of rodents ...	1993	8510115
failure to identify borrelia burgdorferi in southern california ticks by dna amplification.		1993	8515128
genetic diversity among borrelia burgdorferi isolates from wood rats and kangaroo rats in california.	twenty-nine borrelia burgdorferi isolates, obtained from dusky-footed wood rats (neotoma fuscipes) and california kangaroo rats (dipodomys californicus) in california, were analyzed genetically. chromosomal dna was examined by restriction endonuclease analysis (rea) and gene probe restriction fragment length polymorphism. pulsed-field gel electrophoresis was used to analyze the plasmid profiles of the isolates. rea, the method with the greatest discrimination, disclosed 24 distinct restriction p ...	1993	7905880
natural and experimental borrelia burgdorferi infections in woodrats and deer mice from california.	sequestration of spirochetes and concurrent histopathologic lesions were evaluated in tissues of borrelia burgdorferi-infected dusky-footed woodrats (neotoma fuscipes) and deer mice (peromyscus maniculatus). rodents were either wild-caught and naturally infected or were experimentally infected by tick bite, by intramuscular (i.m.) injection of cultured spirochetes, or by i.m. injection of tick suspensions. samples of host tissues, including skin, blood, ear, brain, eye, heart, lung, liver, splee ...	1994	7933283
lyme disease in northwestern coastal california.	to determine the incidence of physician-diagnosed lyme disease in an endemic area of california, an active surveillance program was implemented in lake, mendocino, sonoma, and southern humboldt counties. more than 200 medical care providers were called monthly for their list of suspected cases of lyme disease. pertinent information was abstracted from the medical record of each patient. of 153 cases of possible early lyme disease ascertained from july 1991 to december 1992, 37% consisted of phys ...	1994	8053175
the use of serologic tests for lyme disease in a prepaid health plan in california.	to determine the reason(s) why serologic tests for lyme disease are performed, who initiates the test requests, and how the test results are used in a clinical setting.	1994	8080498
antibody prevalence of eight ruminant infectious diseases in california mule and black-tailed deer (odocoileus hemionus).	we tested 276 sera from 18 free-ranging black-tailed and mule deer (odocoileus hemionus) herds in california (usa) collected from 1987 to 1991 in five biogeographical habitat types, for antibodies against eight infectious disease agents. overall antibody prevalence was 56% for anaplasma marginale, 31% for borrelia burgdorferi, 16% for bluetongue virus serotype 17, 15% for epizootic hemorrhagic disease virus, 7% for coxiella burnetii and toxoplasma gondii, respectively, and 0% for bovine leukosis ...	1994	8151824
genotypic and phenotypic characterization of borrelia burgdorferi isolated from ticks and small animals in illinois.	we have characterized 33 isolates of borrelia burgdorferi from northern illinois (32 isolates) and wisconsin (1 isolate) representing the largest series of midwestern isolates investigated to date. the techniques used for molecular analysis of strains included (i) genospecies typing with species-specific pcr primers, (ii) plasmid profiling by pulsed-field gel electrophoresis of total genomic dna, (iii) large-restriction-fragment pattern (lrfp) analysis by pulsed-field gel electrophoresis of mlui ...	1995	7494019
lyme disease.	in the united states, lyme disease is the most common arthropod-borne infection. the majority of cases are reported from the northeast, the midwest, and california, which are areas with established foci of borrelia burgdorferi. advances in the understanding of the epidemiology of ixodes ticks, the established vector for transmission of lyme disease, provided strategies to reduce tick populations and the risk of acquiring disease. genotypic diversity of subspecies of b. burgdorferi has been assoc ...	1995	7547110
evidence implicating nymphal ixodes pacificus (acari: ixodidae) in the epidemiology of lyme disease in california.	to clarify the role of nymphal versus adult western black-legged ticks (ixodes pacificus) in the epidemiology of lyme disease, the seasonal distribution, abundance, and spirochetal infection rates in these stages, and the seasonal occurrence of ticks biting humans and of incident cases of lyme disease were determined in northern california. although their seasonal activity periods overlapped for about one-third of the year, nymphs and adults predominated in different seasons, the former from lat ...	1995	7573703
multivariate morphometric discrimination of nymphal and adult forms of the blacklegged tick (acari: ixodidae), a principal vector of the agent of lyme disease in eastern north america.	a morphological study of postlarval stages of the blacklegged tick, ixodes scapularis say, was conducted to examine congruence between northern (formerly i. dammini spielman, clifford, piesman & corwin) and southern morphotypes. the character set totaled 17 for females, 25 for males, and 28 for nymphs. populations from 6 geographic areas, f1 progeny from reciprocal crosses between i. scapularis from massachusetts and georgia, and i. pacificus cooley & kohls from california were measured. charact ...	1995	8551506
case-control study of risk factors for incident lyme disease in california.	to identify risk factors for incident lyme disease in california during the period june 1, 1991 to december 31, 1992, the authors compared the activities of 101 cases of physician-diagnosed erythema migrans ascertained via both active and passive surveillance with those of 107 controls matched on sex, age, and neighborhood. questions asked by telephone pertained to location of home, presence of wildlife around the house, hours of outdoor work and outdoor leisure activities, pet ownership, precau ...	1995	7572986
two geographically distinct isolates of borrelia burgdorferi from the united states share a common unique ancestor.	the genetic diversity of borrelia burgdorferi isolates from several geographic regions was evaluated by nucleotide sequence analysis of the genes encoding 23s ribosomal rna and outer surface protein a. comparison of nucleotide sequences spanning 738 bp of the 23s ribosomal dna from two unusual isolates, dn127 (del norte county, california) and 25015 (millbrook, new york), to homologous sequences from other b. burgdorferi isolates from the united states and russia identified several nucleotide se ...	1995	8525058
reservoir competence of four chaparral-dwelling rodents for borrelia burgdorferi in california.	aspects of the reservoir competence of four rodents for the lyme disease spirochete, borrelia burgdorferi, were evaluated in california. rodents were live-trapped and ear-punch biopsies were cultured during each season. a second set of biopsies was cultured from representative individuals after 2-3 weeks of captivity and the results of culturing biopsies taken on both dates were compared with the results of feeding ixodes pacificus larvae on hosts xenodiagnostically. the prevalence of infections ...	1996	8651378
ixodes (ixodes) jellisoni and i. (i.) neotomae (acari:ixodidae): descriptions of the immature stages from california.	nymphal and larval stages of ixodes (ixodes) jellisoni cooley & kohls and i. (i.) neotomae cooley are described for the first time. these 2 tick species occur only in the western united states, predominantly in california. the primary host for i. jellisoni is the california kangaroo rat, dipodomys californicus (merriam); that for i. neotomae is the dusky-footed woodrat, neotoma fuscipes baird. the etiologic agent of lyme disease borrelia burgdorferi johnson, schmidt, hyde, steigerwalt & brenner ...	1996	8667376
evaluation of permethrin-impregnated cotton balls as potential nesting material to control ectoparasites of woodrats in california.	the dusky-footed woodrat, neotoma fuscipes baird is a natural reservoir of the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, in california. to investigate the potential of host-targeted insecticide to control the tick vectors of b. burgdorferi, permethrin-impregnated or untreated cotton balls were distributed in metal cylinders as potential nesting material adjacent to 95 woodrat houses in chaparral-covered rangeland. laboratory experiments demonstra ...	1996	8667381
comparison of infectivities of six tick-derived isolates of borrelia burgdorferi for rodents and ticks.	the infectivity and dissemination to the skin of six isolates of borrelia burgdorferi were evaluated by inoculating them into groups of deer mice (peromyscus maniculatus), hamsters, and swiss webster mice. rodent infection was assayed by culture of ear punch biopsy specimens taken at 4, 8, and 12 weeks postinoculation (p.i.). spirochetes were detected in biopsy specimens from individuals of all three host species that had been inoculated with four isolates (ca3, ca4, ca7, and ca8). ear punch bio ...	1996	8748276
risk of human exposure to vector ticks (acari: ixodidae) in a heavily used recreational area in northern california.	the risk of humans encountering vector ticks along hiking trails or in picnic grounds in a lyme disease-endemic area was evaluated in a multipurpose recreational area (tilden regional park) in the populous san francisco bay region of california. four hillside hiking trails (two high-use, two low-use) were sampled by dragging and walking through low vegetation biweekly for one year; four heavily used picnic areas were sampled concurrently by dragging. adults of three human-biting ticks were enume ...	1996	8780455
compatibility of two species of ixodes ticks with murid hosts and its effect on transmission of lyme disease spirochaetes.		1996	8887343
seroepidemiology of emerging tickborne infectious diseases in a northern california community.	a seroprevalence and risk factor study of emerging tickborne infectious diseases (lyme disease, ehrlichiosis, and babesiosis) was conducted among 230 residents of a semirural community in sonoma county, california. over 50% of residents reported finding a tick on themselves in the preceding 12 months. samples from 51(23%) residents were seroreactive to antigens from one or more tickborne disease agents: 1.4% to borrelia burgdorferi, 0.4% to ehrlichia equi, 4.6% to ehrlichia chaffeensis, and 17.8 ...	1997	9180183
population genetic structure of ixodes pacificus (acari:ixodidae) using allozymes.	genetic analysis of the population structure of the western blacklegged tick, ixodes pacificus cooley & kohls, was conducted using allozymes. this vector tick transmits the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, in the far-western united states. it ranges from british columbia to baja california and disjunct populations are present in oregon, nevada, utah, and arizona. host-seeking adult ticks were collected from vegetation across the range of ...	1997	9220679
role of small mammals in the ecology of borrelia burgdorferi in a peri-urban park in north coastal california.	the role of small mammals other than woodrats in the enzootiology of the lyme disease spirochete, borrelia burgorferi, was assessed in the peri-urban park. mammals were collected monthly from september through to april. following tick removal, the animals were tested for b. burgdorferi by culture of ear-punch biopsies. larvae and nymphs that were intermediate in morphology between ixodes spinipalpis and ixodes neotomae occurred on several species of rodents (peromyscus truei, peromyscus californ ...	1997	9291589
expanded diversity among californian borrelia isolates and description of borrelia bissettii sp. nov. (formerly borrelia group dn127).	up to now, the only species in the complex borrelia burgdorferi sensu lato known to cause lyme borreliosis in the united states has been b. burgdorferi sensu stricto. however, some atypical strains closely related to the previously designated genomic group dn127 have been isolated in the united states, mostly in california. to explore the diversity of b. burgdorferi sensu lato group dn127, we analyzed the nucleotide sequences of the rrf-rrl intergenic spacer regions from 19 atypical strains (18 ...	1998	9817861
detection of the agents of human ehrlichioses in ixodid ticks from california.	a study was conducted in northern california to estimate the prevalence and distribution in ixodid ticks of the rickettsial agents of human monocytic (hme) and human granulocytic (hge) ehrlichioses. more than 650 ixodid ticks were collected from 17 sites in six california counties over a 15-month period. ehrlichia chaffeensis, the causative agent of hme, was detected by a nested polymerase chain reaction (pcr) in ixodes pacificus (minimum infection rate [mir] = 13.3%) and dermacentor variabilis ...	1999	9988324
population genetics and phylogenetic analysis of colorado borrelia burgdorferi.	borrelia burgdorferi is transmitted in an enzootic cycle in colorado between the tick ixodes spinipalpis and the woodrat neotoma mexicana. the genetic relationship of colorado isolates to other b. burgdorferi isolates is unknown nor have relationships among various colorado isolates been determined. portions of the flagellin (fla), 66-kd protein, and outer surface protein a (ospa) genes were amplified from 71 colorado isolates, screened for genetic variability using single strand conformation po ...	1999	10348251
variation in the density of questing ixodes pacificus (acari:ixodidae) nymphs infected with borrelia burgdorferi at different spatial scales in california.	the density of, and prevalence of infection with borrelia burgdorferi in, ixodes pacificus nymphs as well as the density of infected nymphs were compared at 12 properties at a small rural community at high risk for lyme disease (chr) and at 12 areas at the university of california hopland research and extension center (hrec), mendocino county, california. the mean infection prevalence and density of infected nymphs were 1.7% (range, 0-4.2%) and 0.10 infected nymphs per 100 m2 (range, 0-0.23 per ...	1999	10577716
abundance of ticks (acari: ixodidae) infesting the western fence lizard, sceloporus occidentalis, in relation to environmental factors.	we examined the impact of environmental characteristics, such as habitat type, topographic exposure and presence of leaf litter, on the abundance of ixodes pacificus ticks infesting the western fence lizard (sceloporus occidentalis) at the university of california hopland research and extension center (hrec), mendocino county, california. a total of 383 adult lizards were slip-noosed and examined for tick infestation in april and may 1998. at least 94% of the lizards were infested by ticks and a ...	1999	10581712
mitochondrial dna sequence variation in ixodes pacificus (acari: ixodidae).	the western black-legged tick, ixodes pacificus, is a primary vector of the spirochaete, borrelia burgdorferi, that causes lyme disease. we used variation in a 355-bp dna portion of the mitochondrial cytochrome oxidase iii gene to assess the population structure of the tick across its range from british columbia to southern california and east to utah. ixodes pacificus showed considerable haplotype diversity despite low nucleotide diversity. maximum parsimony and isolation-by-distance analyses r ...	1999	10583539
anti-arthropod saliva antibodies among residents of a community at high risk for lyme disease in california.	the role of the western black-legged tick (ixodes pacificus) versus that of other potential arthropod vectors in the epidemiology of lyme disease was evaluated by determining the prevalence of anti-arthropod saliva antibodies (aasa) among residents (n = 104) of a community at high-risk (chr). salivary gland extracts prepared from i. pacificus, the pacific coast tick (dermacentor occidentalis), the western cone-nose bug (triatoma protracta), and the western tree-hole mosquito (aedes sierrensis) w ...	1999	10586924
canines as sentinels for lyme disease in san diego county, california.	prevalence of lyme borreliosis in canine sentinels has been shown to correlate with infection in humans. one thousand canine sera (917 dogs, 83 coyotes) obtained from animal control authorities and area veterinarians were screened by elisa for antibodies to borrelia burgdorferi. results were validated by western blot and indirect fluorescent antibody (ifa) tests at referee laboratories. criterion for a positive western blot was presence of 5 of 10 of the most common antigen igg bands; for ifa, > ...	2000	10730940
vector competence of ixodes angustus (acari: ixodidae) for borrelia burgdorferi sensu stricto.	the vector competence of ixodes angustus for borrelia burgdorferi sensu stricto (s.s.) was investigated in the laboratory. the larval progeny of female ticks from washington state were placed on swiss-webster mice that had been inoculated intravenously with 10(8) spirochetes each of a californian isolate of b. burgdorferi. spirochetes were detected in 6 (12%) of 50 nymphs derived from larvae that had fed on these animals. ten nymphs from the same cohort of experimentally infected ticks were plac ...	2000	10823359
evaluation of host preferences by helminths and ectoparasites among black-tailed jackrabbits in northern california.	fifty-four black-tailed jackrabbits (lepus californicus) (five juvenile males, 22 adult males, five juvenile females, and 22 adult females) from humboldt county, california (usa) were evaluated for sex and age-specific differences in parasite prevalences and intensities, 26 february through 30 october 1996. nematodes found included biogastranema leporis in 42 hares (78% prevalence), rauschia triangularis in 26 hares (48%), trichostrongylus calcaratus in 14 hares (26%), and trichuris sylvilagi in ...	2000	10941744
density and spatial distribution of ixodes pacificus (acari: ixodidae) in two recreational areas in north coastal california.	the density and distribution of ixodes pacificus was assessed at 2 parks in north coastal california. the density of i. pacificus adults and nymphs varied significantly between years, trails, and sides of trails. adult ticks occurred on vegetation along sun-exposed trails in january through march, their density (0-1.93 per 20 m) correlated with brush density, trail width, and presence of an uphill slope. nymphs (0.06-5.10 per 20 m) occurred in leaf litter along shaded trails in may-july. adult i ...	2000	11037789
serologic survey for selected infectious disease agents in swift and kit foxes from the western united states.	a serologic survey of swift fox (vulpes velox) and kit fox (v. macrotis) from the western usa was conducted for 12 infectious diseases. samples from swift fox were collected between 1987 and 1992 from colorado (n = 44), kansas (n = 10), and wyoming (n = 9). samples from kit fox were collected in california (n = 86), new mexico (n = 18), utah (n = 9), and arizona (n = 6). overall antibody prevalence rates were 33 of 110 (30%) for canine parvovirus (cpv), 9 of 72 (13%) for canine distemper virus ( ...	2000	11085448
ecology of borrelia burgdorferi in ticks (acari: ixodidae), rodents, and birds in the sierra nevada foothills, placer county, california.	this study examined the prevalence of borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner in host-seeking adult and nymphal ixodes pacificus cooley & kohls and estimated the i. pacificus infestation and b. burgdorferi infection of rodent and avian hosts in the western sierra nevada foothills of northern california. additionally, we identified species likely to participate in an enzootic cycle for b. burgdorferi in this yellow pine transition habitat. evidence of infection with b. b ...	2000	11126549
molecular evidence of bartonella spp. in questing adult ixodes pacificus ticks in california.	ticks are the vectors of many zoonotic diseases in the united states, including lyme disease, human monocytic and granulocytic ehrlichioses, and rocky mountain spotted fever. most known bartonella species are arthropod borne. therefore, it is important to determine if some bartonella species, which are emerging pathogens, could be carried or transmitted by ticks. in this study, adult ixodes pacificus ticks were collected by flagging vegetation in three sites in santa clara county, calif. pcr-res ...	2001	11283031
birds and their ticks in northwestern california: minimal contribution to borrelia burgdorferi enzootiology.	birds and their attendant ticks were surveyed for infection with the lyme disease spirochete borrelia burgdorferi, in chaparral and woodland-grass habitats in northwestern california from march to july, 1998 to 1999. in total, 234 birds were captured and recaptured (15%); nearly 2.5 times more birds were captured in chaparral than in woodland-grass. overall, 34 species representing 15 families were collected during this study; of these, 24 species were caught in chaparral, 19 in woodland-grass, ...	2001	11534638
persistent infection in neotoma fuscipes (muridae: sigmodontinae) with ehrlichia phagocytophila sensu lato.	dusky-footed wood rats (neotoma fuscipes baird) and two species of peromyscus mice (p. maniculatus wagner and p. truei shufeldt) were collected over a 16-month period from three sites in sonoma county, california. blood was collected from 93 wood rats and 177 mice and serum or plasma was tested for seroreactivity with ehrlichia phagocytophila sensu lato (also known as the human granulocytic ehrlichiosis agent). thirty-five (37.6%) wood rats and 15 (8.5%) mice were seropositive. positive neotoma ...	2001	11693866
prevalence and abundance of ixodes pacificus immatures (acari: ixodidae) infesting western fence lizards (sceloporus occidentalis) in northern california: temporal trends and environmental correlates.	the prevalence and abundance of immature ixodes pacificus ticks on western fence lizards (sceloporus occidentalis) were examined in relation to time of year, host attributes (i.e., age, gender, and presence or absence of blood parasites), and 5 environmental characteristics, including topographic exposure and ground cover substrate, over a 2-year period in northern california. lizards were infested with subadult ticks from early march until late july or early august, with peak median numbers of ...	2001	11780813
acarologic risk of exposure to emerging tick-borne bacterial pathogens in a semirural community in northern california.	an acarologic study was conducted in a semirural community in northern california to determine the relative abundance of, and the prevalence of infection with, three emerging bacterial pathogens in the western black-legged tick (ixodes pacificus). these included the agents causing lyme disease (borrelia burgdorferi), human granulocytic ehrlichiosis [ehrlichia phagocytophila (formerly ehrlichia equi)], and human monocytic ehrlichiosis (ehrlichia chaffeensis). the study area in sonoma county consi ...	2001	12653148
detection of borrelia burgdorferi, ehrlichia chaffeensis, and anaplasma phagocytophilum in ticks (acari: ixodidae) from a coastal region of california.	a study was conducted in santa cruz county to estimate the prevalence and distribution of the agents of lyme disease, human granulocytic (hge), and human monocytic (hme) ehrlichiosis in 1,187 adult ixodid ticks collected from eight public-use recreation areas over a 2-yr period. borrelia burgdorferi, the causative agent of lyme disease, was detected by a polymerase chain reaction (pcr) in 44 of 776 (5.67%) ixodes pacificus ticks and in 3 of 58 (5.17%) dermacentor variabilis ticks. anaplasma phag ...	2003	14680123
the western black-legged tick, ixodes pacificus, in the sutter buttes.	the western black-legged tick, ixodes pacificus, was collected from huff canyon in the sutter buttes in north central california, sutter county. the sutter buttes are within the sacramento valley and outside the normal distribution of i. pacificus in california. adult i. pacificus were collected via flagging as they quested along deer trails; subadult life stages were collected from three species of lizard, elgaria multicarinata, sceloporus occidentalis, and s. graciosus. adult ticks were tested ...	2003	14714665
acarologic risk of exposure to borrelia burgdorferi spirochaetes: long-term evaluations in north-western california, with implications for lyme borreliosis risk-assessment models.	over a 5-year period (1997-2001) the population densities of ixodes pacificus cooley & kohls (acari: ixodidae) nymphs infected with spirochaetes of borrelia burgdorferi sensu lato (s.l.) were evaluated in areas of 2000 ha at two localities (chr, nine sites; hrec, seven sites) 25 km apart in mendocino county, north-western california. the 5-year median density of infected nymphs was significantly higher at chr than at hrec (0.51 vs. 0.09 per 100 m(2) and site-specific yearly densities exceeding o ...	2004	15009444
human behaviors elevating exposure to ixodes pacificus (acari: ixodidae) nymphs and their associated bacterial zoonotic agents in a hardwood forest.	epidemiological evidence suggests that the nymph of the western black-legged tick, ixodes pacificus cooley and kohls, is the primary vector of the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt, and brenner, to humans in northwestern california. in spring 2002, six different human behaviors were evaluated as potential risk factors for acquiring i. pacificus nymphs in a deciduous woodland in mendocino county, california. also, the prevalence of b. burgdorferi sen ...	2004	15061284
ecology of anaplasma phagocytophilum and borrelia burgdorferi in the western united states.	we discuss the ecology of anaplasma phagocytophilum and borrelia burgdorferi in the western u.s. these agents, while emerging in the eastern u.s., remain stable or rare in the west. in the western u.s., tick vectors and mammalian hosts for b. burgdorferi and a. phagocytophilum are distinct from those in the eastern u.s. and considerably more variable. spatial complexity, local extinctions, and low levels of movement among foci may determine the distribution and prevalence of these agents. high-p ...	2004	15266739
the roles of birds, lizards, and rodents as hosts for the western black-legged tick ixodes pacificus.	we compared the infestation by ixodid ticks of lizards, rodents, and birds collected simultaneously within areas representing common habitat types in mendocino county, ca. lizards were infested only by ixodes pacificus cooley and kohls, birds by i. pacificus and haemaphysalis leporispalustris (packard), and rodents by i. pacificus, i. spinipalpis hadwen and nuttall, i. woodi bishopp, dermacentor occidentalis marx, and d. variabilis (say). infestation by i. pacificus larvae and nymphs of lizards ...	2004	15709249
detection and characterization of borrelia bissettii in rodents from the central california coast.	this is the first report of borrelia burgdorferi sensu lato in rodents from san luis obispo county, with most isolates obtained from a previously unreported host, neotoma lepida thomas. b. burgdorferi sensu lato was identified in seven rodent species, including the california vole, microtus californicus peale; dusky-footed woodrat, neotoma fuscipes baird; desert woodrat, neotoma lepida thomas; brush mouse, peromyscus boylii baird; california mouse, peromyscus californicus gambel; deer mouse, per ...	2004	15311469
life stage-related differences in density of questing ticks and infection with borrelia burgdorferi sensu lato within a single cohort of ixodes pacificus (acari: ixodidae).	the primary aims of this study were to quantify the density of ixodes pacificus cooley and kohls nymphs and adults of the same generational cohort collected within a single year in six oak or madrone leaf litter habitats and to compare the prevalence of infection with borrelia burgdorferi sensu lato (s.l.) in adults originating from nymphal cohorts with a low (<1%) versus high (>10%) infection prevalence. because adult densities were very low both in and adjacent to several sites, direct compari ...	2004	15311473
habitat-related variation in infestation of lizards and rodents with ixodes ticks in dense woodlands in mendocino county, california.	during the spring and early summer of 2002, we examined the relative importance of borrelia-refractory lizards (sceloporus occidentalis, elgaria spp.) versus potential borrelia burgdorferi sensu lato (s.l.)-reservoirs (rodents) as hosts for ixodes pacificus immatures in 14 woodland areas (six oak, five mixed oak/douglas fir, and three redwood/tanoak areas) distributed throughout mendocino county, california. lizards were estimated to serve as hosts for 93-98% of all larvae and > or =99.6% of all ...	2004	15347025
remote sensing (normalized difference vegetation index) classification of risk versus minimal risk habitats for human exposure to ixodes pacificus (acari: ixodidae) nymphs in mendocino county, california.	in california, ixodes pacificus cooley & kohls nymphs have been implicated as the primary bridging vectors to humans of the spirochetal bacterium causing lyme disease (borrelia burgdorferi). because the nymphs typically do not ascend emergent vegetation, risk of human exposure is minimal in grasslands, chaparral, and woodland-grass. instead, woodlands with a ground cover dominated by leaf litter (hereinafter referred to as woodland-leaf) have emerged as a primary risk habitat for exposure to b. ...	2005	15691012
columbian black-tailed deer (odocoileus hemionus columbianus) as hosts for borrelia spp. in northern california.	the prevalence of infection of columbian black-tailed deer (odocoileus hemionus columbianus) with borrelia spp. was evaluated in an area of northwestern california (usa) where lyme disease is endemic and the relapsing-fever group spirochete borrelia coriaceae is enzootic, and in a far-removed comparison area having a disparate climate and lower density of vector ticks. blood samples collected from both deer herds in 1987, 1988, and from 2000-02 were assayed for borrelial infection with microscop ...	2005	15827217
gis-facilitated spatial epidemiology of tick-borne diseases in coyotes (canis latrans) in northern and coastal california.	ixodes pacificus is the main tick vector for transmission of anaplasma phagocytophilum and borrelia burgdorferi to large vertebrates in california. the present study was undertaken in i. pacificus-infested counties in california to examine spatial and temporal relationships among a. phagocytophilum and b. burgdorferi-exposed coyotes with vegetation type and climate. the overall a. phagocytophilum and b. burgdorferi seroprevalences were 39.5% (n=215) and 18.9% (n=148), respectively, with no assoc ...	2005	15857659
western gray squirrel (rodentia: sciuridae): a primary reservoir host of borrelia burgdorferi in californian oak woodlands?	in california, dense woodlands have been recognized as important biotopes where humans are exposed to the nymphal stage of the western blacklegged tick, ixodes pacificus cooley & kohls, the primary vector of the lyme disease spirochete borrelia burgdorferi sensu stricto (s.s.), in the far-western united states. to identify the principal reservoir host(s) of this spirochete, and of closely related spirochetes in the b. burgdorferi sensu lato (s.l.) complex, in dense woodlands in mendocino county, ...	2005	15962792
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
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
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
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
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
association between polyarthritis and thrombocytopenia and increased prevalence of vectorborne pathogens in californian dogs.		2007	17277299
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
spatial analysis of the exposure of dogs in rural north-coastal california to vectorborne pathogens.	between 0 and 50 per cent of the dogs in eight rural villages in far northern california with a high risk of tickborne diseases were seropositive for anaplasma phagocytophilum and bartonella vinsonii subspecies berkhoffii, and between 0 and 10 per cent were seropositive for borrelia burgdorferi. the odds ratio for the co-exposure of individual dogs to b vinsonii berkhoffii and a phagocytophilum was 18.2. none of the diseases was associated with the sex of the dogs, whether they slept out of door ...	2007	17993656
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
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
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
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
horizontal and vertical movements of host-seeking ixodes pacificus (acari: ixodidae) nymphs in a hardwood forest.	the nymph of the western black-legged tick (ixodes pacificus) is an important bridging vector of the lyme disease spirochete (borrelia burgdorferi) to humans in the far-western united states. the previously unknown dispersal capabilities of this life stage were studied in relation to logs, tree trunks, and adjacent leaf-litter areas in a mixed hardwood forest using mark-release-recapture methods. in two spatially and temporally well-spaced trials involving logs, the estimated mean distances that ...	2009	20352083