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bacteriophage in the ixodes dammini spirochete, etiological agent of lyme disease.a bacteriophage with a b-3 morphology was detected by electron microscopy in a spirochete isolated from the tick ixodes dammini. it has a 40- to 50-nm elongated head and a tail 50 to 70 nm in length. it appears devoid of collars or kite-tail structure. the spirochete has been identified as the causative agent of lyme disease.19836853449
susceptibility of the black-legged tick, ixodes scapularis, to the lyme disease spirochete, borrelia burgdorferi.experiments to determine whether ixodes scapularis can be infected with the lyme disease agent, borrelia burgdorferi, demonstrated that infection and transstadial transmission occurs in up to 73% of larval ticks that had fed on spirochetemic rabbits. in a limited number of nymphal ticks examined, the spirochetes were found only in the midgut. feeding nymphal i. scapularis on a normal rabbit resulted in blood infection characterized by two distinct periods of spirochetemia, suggesting the occurre ...19863577477
susceptibility of the hispid cotton rat (sigmodon hispidus) to the lyme disease spirochete (borrelia burgdorferi).the susceptibility of the hispid cotton rat, sigmodon hispidus, to the lyme disease spirochete, borrelia burgdorferi, was investigated by inoculating rats with infected tick suspensions or by allowing infected ixodes scapularis nymphs to feed on them. culture of blood samples in bsk ii medium demonstrated that cotton rats developed spirochetemias that lasted for a minimum of 3 to 4 weeks and were of sufficient concentration to infect simultaneously feeding normal i. scapularis nymphs. the spiroc ...19873688316
reservoir competence of white-footed mice for lyme disease spirochetes.using the vector tick, ixodes dammini, we described the reservoir competence of the white-footed mouse, peromyscus leucopus, for the lyme disease spirochete, borrelia burgdorferi. nymphal i. dammini were used to infect mammals, and larval ticks were used to diagnose infection (a form of xenodiagnosis). one tick was nearly as efficient as more than 1 in transmitting the spirochete to mice. the duration of the prepatent period was about 1 week. prevalence of infection approached 100% in ticks that ...19873812887
duration of tick attachment and borrelia burgdorferi transmission.nymphal ixodes dammini transmitted borrelia burgdorferi to 1 of 14 rodents exposed for 24 h, 5 of 14 rodents exposed for 48 h, and 13 of 14 rodents exposed for greater than or equal to 72 h. prompt removal of attached ticks is a prudent public health measure, especially in regions where lyme disease is endemic.19873571459
adult ixodes dammini on rabbits: a hypothesis for the development and transmission of borrelia burgdorferi.a histological study of unfed ixodes dammini adults has shown that the lyme disease spirochete can be found in the midgut diverticula of these ticks and is presumably carried over from the nymphal stage. sequential histology of the early stages of ticks feeding on a rabbit showed that spirochetes began to divide and were located in close proximity or attached to the epithelial cells of the diverticulae. evidence for division was obtained by the higher number of spirochetes per tick after a three ...19873572040
prevalence of borrelia burgdorferi in white-footed mice and ixodes dammini at fort mccoy, wis.borrelia burgdorferi, the causative agent of lyme disease, was isolated from 15 of 17 white-footed mice (peromyscus leucopus) and 54 of 82 subadult ixodes dammini from fort mccoy, wis. of the 47 isolates tested, all reacted in indirect fluorescent-antibody tests with monoclonal antibodies directed against a surface protein of b. burgdorferi (approximate molecular weight, 31,000) and flagellins that are common to all borrelia species. indirect fluorescent-antibody reactions were variable when an ...19873305566
simultaneous transmission of borrelia burgdorferi and babesia microti by individual nymphal ixodes dammini ticks.nymphal ixodes dammini ticks, selected from a group of ticks in which 22 of 31 (71%) contained dual borrelia burgdorferi and babesia microti infections, simultaneously transmitted b. burgdorferi and b. microti to 4 of 7 (57%) hamsters exposed to individual ticks.19873667924
ability to ixodes scapularis, dermacentor variabilis, and amblyomma americanum (acari: ixodidae) to acquire, maintain, and transmit lyme disease spirochetes (borrelia burgdorferi). 19883193425
deer ticks, ixodes dammini (acari: ixodidae), and lyme disease spirochetes, borrelia burgdorferi, in maine. 19883404548
epizootiology of borrelia in ixodes tick vectors and reservoir hosts.four north american and two european species of ixodes ticks harbor borreliae. three of the north american species--ixodes dammini, ixodes scapularis, and ixodes pacificus--and two old world species--ixodes ricinus and ixodes persulcatus--feed on a wide range of hosts, including humans; the north american ixodes dentatus has a predilection for cottontail rabbits and rarely parasitizes humans. in lyme disease foci in north america where i. dammini is common, borrelia burgdorferi or similar types ...19892682957
restriction endonuclease analysis of four borrelia burgdorferi strains.a restriction endonuclease analysis was performed on four strains of borrelia burgdorferi: one isolated from man (sf), one from ixodes dammini (b31) and two from i. ricinus (bits in italy and b45 in germany). digestion by taq i and hae iii gave the best resolution of the dna fragments. three different restriction patterns were obtained: bits and b45 showed only one band difference. these results correlate with the reactivity of the four strains with monoclonal antibodies.19892560664
detection of borrelia burgdorferi dna in museum specimens of ixodes dammini ticks.in order to investigate the potential for borrelia burgdorferi infection before the recognition of lyme disease as a clinical entity, the polymerase chain reaction (pcr) was used to examine museum specimens of ixodes dammini (deer ticks) for the presence of spirochete-specific dna sequences. one hundred and thirty-six archival tick specimens were obtained representing various continental u.s. locations; dna sequences characteristic of modern day isolates of b. burgdorferi were detected in 13 194 ...19902402635
borrelia burgdorferi and ixodes dammini prevalent in the greater philadelphia area. 19902319174
bird-feeding ticks transstadially transmit borrelia burgdorferi that infect syrian hamsters.bird-feeding ixodes dammini ticks were documented for the first time to successfully molt and transstadially pass borrelia burgdorferi spirochetes that were indistinguishable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis from the type b31 strain. forty-six of 73 blood-engorged larvae and 50 of 66 fully-fed nymphs, removed from wild-caught birds, successfully molted. borreliae were isolated from 21 of 78 partially- and fully-fed larvae off birds, including six specimens that molted ...19902304189
tick parasitism and antibodies to borrelia burgdorferi in cats.ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to borrelia burgdorferi. twenty-two of 93 cats (23.7%) had one or more motile stages of ixodes dammini attached. of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with b burgdorferi. spirochetes were not found in tissues of 13 female and 4 male ticks. ten of 71 serum samples analyzed by indirect fluorescent antibody staining or elisa contained antibodies to ...19902196252
experimental infection of the white-footed mouse with borrelia burgdorferi.laboratory raised white-footed mice (peromyscus leucopus) were inoculated experimentally with live spirochetes (borrelia burgdorferi), the etiologic agent of lyme disease (borreliosis). prior to inoculation, mouse sera were tested with an indirect fluorescent antibody test, and all mice were seronegative. all inoculated mice seroconverted. in tick transmission studies, immature stages of ixodes dammini and dermacentor variabilis attached and fed to repletion on mice, but only i dammini transferr ...19902085225
isolation of borrelia burgdorferi from arthropods collected in texas.the texas department of health laboratory cultured arthropods from november 1988 through december 1989 in an attempt to isolate borrelia burgdorferi, the etiologic agent of lyme disease. spirochetes were isolated from eight of 1,093 pools of arthropods cultured. the spirochetal isolates were from several tick and one flea species, including amblyomma americanum, a. maculatum, ixodes scapularis, and ctenocephalides felis. these 8 isolates reacted specifically when treated with monoclonal antibodi ...19912063950
duration of adult female ixodes dammini attachment and transmission of borrelia burgdorferi, with description of a needle aspiration isolation method.the relationship between the attachment duration of adult female ixodes dammini and the transmission of borrelia burgdorferi was studied. sixteen rabbits were exposed to spirochete-infected female ticks for specified intervals. all five rabbits exposed to ticks that fed to repletion (greater than 120 h) became infected, as did two of three exposed for 48 h. in contrast, five rabbits exposed to a cumulative total of 53 infected female i. dammini for 36 h failed to become infected, as did three ra ...19912010643
lyme disease in south carolina.lyme disease is present in south carolina, though not as prevalent as in many other states in the country. the characteristics of south carolina cases are similar to those of the nation as a whole. the tick vector of lyme disease in the southeast is not clearly established, but is thought to be ixodes scapularis. questions remain concerning the prevalence of infection in local ticks with borrelia burgdorferi, and the risk to a person bitten by a tick in south carolina.19911943029
etiologic agent of lyme disease, borrelia burgdorferi, detected in ticks (acari: ixodidae) collected at a focus in alabama.the study was conducted at sites of known transmission of borrelia burgdorferi in east central alabama. the objectives were to determine species of ticks present at these sites, their host associations, and species of ticks and small mammals naturally infected with b. burgdorferi. a total of 451 hosts were examined for ticks, including cotton mice, peromyscus gossypinus (le conte); cotton rats, sigmodon hispidus say & ord; southern short-tailed shrews, blarina carolinensis (bachman); house mice, ...19911941933
ixodes scapularis (acari: ixodidae) in kansas: a new distribution record.the blacklegged tick, ixodes scapularis say, previously known to occur only in the extreme southeastern corner of kansas, has been collected in douglas and jefferson counties in the northeast. the new collections extend the northern range of this species in kansas by approximately 240 km. the role of i. scapularis as a vector of the lyme borreliosis spirochete, borrelia burgdorferi, makes this a noteworthy extension of its known range. the proximity of these new collection sites to large centers ...19911770524
isolation and characterization of borrelia burgdorferi from illinois ixodes dammini.ixodes dammini ticks from two northwestern illinois sites were found to be infected with borrelia burgdorferi at rates of 19 and 32%. b. burgdorferi isolates, one from each site, had protein and antigenic patterns similar to those of the b-31 strain. an indirect immunofluorescence method proved to be more sensitive than dark-field microscopy in detection of these spirochetes. a modified bsk medium containing rifampin was found to be more efficient for spirochete isolation than unsupplemented bsk ...19911761698
babesia microti, human babesiosis, and borrelia burgdorferi in connecticut.babesia microti was isolated from a white-footed mouse (peromyscus leucopus) that was captured in southeastern connecticut in 1988, when the first human case of babesiosis acquired in connecticut was recognized. to date, 13 cases of babesiosis have been reported in connecticut, the largest number of human cases reported on the mainland united states. two of nine patients quiried remembered a prior tick bite. since babesia parasites are known to be vectored only by ticks, we surmise that 12 of th ...19911757548
inability of ixodes cookei and amblyomma americanum nymphs (acari: ixodidae) to transmit borrelia burgdorferi.the vector competency of ixodes cookei packard and amblyomma americanum (l.) for borrelia burgdorferi was studied using syrian hamsters. ixodes dammini spielman, clifford, piesman & corwin were used as controls. darkfield and immunofluorescent examinations of midgut diverticula revealed b. burgdorferi spirochetes in 32 of 36 (88.9%) i. dammini larvae, 5 of 36 (13.9%) i. cookei larvae, and 7 of 36 (19.4%) a. americanum larvae within 48 h after feeding on infected syrian hamsters. b. burgdorferi w ...19921625302
an initial investigation of the status of borrellia burgodorferi and its suspected primary vector, ixodes scapularis, in south carolina.based on a survey of hunter-harvested deer, the suspected primary vector of lyme disease in the southeast, i. scapularis, is most prevalent in sandhill and coastal plain counties of south carolina. none of 271 i. scapularis examined were found to be infected with the lyme disease spirochete. however, many more specimens of i. scapularis, a. americanum, and other tick species must be examined before an accurate estimate of the probability of acquiring lyme disease in south carolina can be made.19921564909
distribution, density, and lyme disease spirochete infection in ixodes dammini (acari: ixodidae) on white-tailed deer in maryland.a statewide survey of ticks parasitizing white-tailed deer was carried out in maryland during november 1989 to assess the status of the deer tick, ixodes dammini spielman, clifford, piesman & corwin, the major vector of lyme disease in the northeastern united states. ticks were collected from deer carcasses brought in by hunters at 23 check stations (one per county). a total of 3,437 i. dammini were collected from 538 of 1,281 deer (42%), together with 2,013 dermacentor albipictus (packard) and ...19921552529
borrelia sp. in ticks recovered from white-tailed deer in alabama.six hundred sixty-five hunter-killed white-tailed deer (odocoileus virginianus) from 18 counties in alabama (usa) were examined for ticks. most of the collections were made at state-operated wildlife management areas. four species of ticks (n = 4,527) were recovered: the lone star tick amblyomma americanum (n = 482); the gulf coast tick a. maculatum (n = 11); the winter tick dermacentor albipictus (n = 1,242); and the black-legged tick ixodes scapularis (n = 2,792). fifty-six percent of the tick ...19921512879
attempted transmission of borrelia burgdorferi (spirochaetales: spirochaetaceae) (jdi strain) by ixodes scapularis (acari: ixodidae), dermacentor variabilis, and amblyomma americanum.laboratory-reared ixodes scapularis say, amblyomma americanum (l.), and dermacentor variabilis (say) were fed on new zealand white rabbits experimentally infected with borrelia burgdorferi (jdi strain). at repletion, spirochetes could be detected by dark-field microscopy only in i. scapularis. acquisition rates were 18 and 21%. when previously exposed nymphs of each species were fed on susceptible rabbits, i. scapularis was the only tick of the three species that transmitted b. burgdorferi. when ...19921495078
isolation of borrelia burgdorferi (spirochaetales: spirochaetaceae) from ixodes scapularis and dermacentor albipictus ticks (acari: ixodidae) in oklahoma.borrelia burgdorferi was isolated from ixodes scapularis say and dermacentor albipictus packard that were removed as partially fed adults from white-tailed deer, odocoileus virginianus zimmermann, in oklahoma. isolation in media was accomplished only after homogenates of pooled field-collected ticks were inoculated into laboratory-reared peromyscus leucopus and reisolated from the urinary bladder into bsk ii media. both isolates were confirmed by western blot analysis and reactivity with monoclo ...19921495072
biopsy of canine ear tissue for detection of borrelia burgdorferi following ixodes dammini feeding.a punch biopsy method was developed to detect and cultivate borrelia burgdorferi from canine ear tissue. the biopsy procedure was sensitive in that spirochetes were detected in 100% of the dogs upon which infected ticks had fed. b. burgdorferi could be cultured as early as 6 days after tick feeding at which time the organisms could not be concurrently recovered from peripheral blood. the ear punch biopsy provides a reliable method for sampling live canines and should prove useful for detecting e ...19921490617
a controlled trial of antimicrobial prophylaxis for lyme disease after deer-tick bites.borrelia burgdorferi, which causes lyme disease, is transmitted by deer ticks (lxodes dammini) in the northeastern and midwestern united states. although deer-tick bites are common in areas in which the disease is endemic, there is uncertainty about how to manage the care of persons who are bitten.19921435930
geographic distribution of white-tailed deer with ticks and antibodies to borrelia burgdorferi in connecticut.ticks and blood specimens were collected from white-tailed deer (odocoileus virginianus) in connecticut and analyzed to identify foci for lyme borreliosis. males and females of ixodes scapularis, the chief vector of borrelia burgdorferi, were collected from deer in five of eight counties during 1989-1991. analysis by indirect fluorescent antibody (ifa) staining of midgut tissues showed that prevalence of infection was highest (9.5% of 367 ticks) in south central and southeastern connecticut. inf ...19938256460
experimental infection of the eastern chipmunk (tamias striatus) with the lyme disease spirochete (borrelia burgdorferi).lyme disease, caused by the spirochete borrelia burgdorferi, is endemic in the northeast, north-central, and pacific coastal states of the united states. the eastern chipmunk (tamias striatus) is found throughout the disease-enzootic regions except along the pacific coast, and may serve as an important reservoir host in some locations. to characterize their potential as a host, 11 adult chipmunks were inoculated with 10(5) spirochetes from strains of b. burgdorferi isolated from peromyscus leuco ...19938258849
plasmid modifications in a tick-borne pathogen, borrelia burgdorferi, cocultured with tick cells.we describe an in vitro system that will facilitate molecular analysis of the association between lyme disease spirochetes and vector cells. we cocultured borrelia burgdorferi continuously with two tick cell lines, rae25 (from rhipicephalus appendiculatus) and ide8 (from ixodes scapularis). a clone isolated after twenty-two passages with rae25 cells had lost the largest (49 kb) plasmid, and probes containing information normally encoded on it, including genes for two surface proteins, hybridized ...19938269098
reduced abundance of ixodes scapularis (acari: ixodidae) and lyme disease risk by deer exclusion.the effect of deer exclosures upon the numbers of immature ixodes scapularis say, the vector of lyme disease in the eastern united states, was examined at five sites in westchester county, ny. study areas ranged in size from 6 to 101 ha where deer had been excluded for a period of 25 yr by > 2.4-m-high fencing that surrounded each site. a total area of 40,506 m2 was drag-sampled during the study to measure tick abundance. nymphal densities (ticks per 1,000 m2) averaged 4.6 (range, 1.3-9.6) insid ...19938271246
reduced abundance of ixodes scapularis (acari: ixodidae) with exclusion of deer by electric fencing.to assess the effect of deer exclusion on populations of ixodes scapularis say (formerly i. dammini spielman, clifford, piesman & corwin) in the northeastern united states, host-seeking ticks and ticks on white-footed mice, peromyscus leucopus (rafinesque), were monitored inside and outside a wooded, residential deer exclosure (approximately 3.5 ha) in lyme, ct, in 1991 and 1992. another deer exclosure was added in lyme (approximately 7.4 ha) during 1992. additional sample sites at other residen ...19938271257
isolation and transmission of the lyme disease spirochete from the southeastern united states.the isolation of the lyme disease spirochete (borrelia burgdorferi) from the southeastern united states is reported. three isolates, two from cotton mice (peromyscus gossypinus) and one from the black-legged tick (ixodes scapularis), were recovered from sapelo island, georgia, in july and september 1991. the spirochetes were characterized by indirect fluorescent antibody assay using a battery of five monoclonal antibodies, by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (sds/page) o ...19938346258
relative importance of bird species as hosts for immature ixodes dammini (acari: ixodidae) in a suburban residential landscape of southern new york state.abundance of birds and their tick parasites were estimated in a residential community located in westchester county, ny, where lyme disease is endemic. in total, 36 bird species (416 captures) were collected, of which 25 species (69%) were parasitized by ticks. ixodes dammini spielman, clifford, piesman & corwin composed 96.4% of the 1,067 ticks found on birds. the bird species most heavily parasitized was house wren, troglodytes aedon vieillot (11.1 ixodes dammini per bird). relative density es ...19938360897
spatial and temporal patterns of ixodes scapularis (acari: ixodidae) in southeastern connecticut.the spatial distribution and abundance of host-seeking ixodes scapularis say (formerly i. dammini) were studied in 10 residential sites in woodlands during 1989-1991. in total, 7,385 larval, 2,202 nymphal, 164 female, and 248 male i. scapularis were collected in old lyme, lyme, east haddam, and chester, ct. the majority of host-seeking i. scapularis larvae (84.2%) and nymphs (73.5%) were collected within the woodland plots, whereas a large proportion of the adults were recovered from lawn (36.4% ...19938360900
an ospa antigen-capture enzyme-linked immunosorbent assay for detecting north american isolates of borrelia burgdorferi in larval and nymphal ixodes dammini.an antigen-capture enzyme-linked immunosorbent assay (elisa) was developed for detecting north american isolates of borrelia burgdorferi in larval, nymphal, and adult ticks. the assay uses an anti-ospa monoclonal antibody (h5332) for antigen capture and biotin-labelled polyclonal sera with streptavidinhorseradish peroxidase for signal generation. the assay recognized 15 of 15 north american b. burgdorferi isolates and did not cross-react with spirochete antigens of borrelia hermsii, borrelia tur ...19938432812
an unexpected result from burning vegetation to reduce lyme disease transmission risks.the risk for human infection with lyme disease appears linked to the abundance of infected vector ticks, principally ixodes dammini spielman, clifford, piesman & corwin, in the eastern united states. habitat destruction by burning, although not well studied, has long been considered as an effective alternative to synthetic insecticides as a means of reducing tick populations. we evaluated the effect of a single spring burning of the woodland understory on the transmission risk of lyme disease sp ...19938510127
early and early disseminated phases of lyme disease in the rhesus monkey: a model for infection in humans.we demonstrate that borrelia burgdorferi infection in the rhesus monkey mimics the early and early disseminated phases of human lyme disease. clinical, bacteriological, immunological, and pathological signs of infection were investigated during 13 weeks after inoculation of the spirochete. three animals were given b. burgdorferi (strain jd1) by needle inoculations, six animals were exposed to the bite of b. burgdorferi-infected ixodes dammini ticks, and three animals were uninfected controls. b. ...19938514412
dynamics of borrelia burgdorferi transmission by nymphal ixodes dammini ticks.groups of 25-30 nymphal ixodes dammini infected with borrelia burgdorferi fed on mice for 36, 42, or 48 h. only 1 (7%) of 14 mice exposed for 36 h became infected as did 3 (25%) of 12 mice exposed for 42 h and 6 (75%) of 8 mice exposed for 48 h. the minimum transmission rate calculation for ticks attached for 36 h was 0.5%; for 42 h, 1.5%; and for 48 h, 5.8%. homogenates derived from nonfed "flat" nymphs or nymphs fed for 12 h were not infectious to mice. homogenates derived from nymphs attached ...19938486940
seroepidemiologic survey of borrelia burgdorferi exposure of dairy cattle in wisconsin.an elisa, using purified flagellin of borrelia burgdorferi as the solid-phase antigen, was used to measure antibody concentrations to b burgdorferi in dairy cattle in wisconsin. serum obtained from 5,060 cows in 160 randomly selected herds in the state were tested. serum from an additional 2,600 cattle in barron county, wis, a county with a high annual incidence of b burgdorferi infections in human beings, was also tested. only 7% of the cows that were tested, but 66% of the herds that were test ...19947802388
serologic surveillance for the lyme disease spirochete, borrelia burgdorferi, in minnesota by using white-tailed deer as sentinel animals.to determine the effectiveness of white-tailed deer as sentinel animals in serologic surveillance programs for borrelia burgdorferi, we performed enzyme-linked immunosorbent assay (elisa) and western immunoblotting analyses on 467 deer serum samples. the seropositivity rate in the elisa was 5% for the 150 samples collected at the three sites in which the tick ixodes scapularis was absent. the three sites with established i. scapularis populations had a seropositivity rate of 80% for 317 samples. ...19948150955
suppression of ixodes scapularis (acari: ixodidae) nymphs in a large residential community.to determine the feasibility of suppressing ixodes scapularis say populations in a large, hyperendemic residential community, several rates of granular carbaryl were applied by ground and air to the shrub layer and wooded buffers of a forested residential community during the peak activity period of nymphs. granular carbaryl significantly reduced the abundance of i. scapularis nymphs on peromyscus leucopus raphinesque. control nymphal ticks ranged between 70.0 and 90.3%. the use of properly time ...19948189411
isolation of borrelia burgdorferi from saliva of the tick vector, ixodes scapularis.a method for cultivating and isolating lyme disease spirochetes, borrelia burgdorferi, from the saliva of vector ticks, ixodes scapularis (formerly known as ixodes dammini), is described. saliva was collected from partially engorged ticks after application of pilocarpine to induce salivation. b. burgdorferi was isolated from 8 of 14 (57%) of the saliva samples derived from ticks infected with the bacteria, as determined by direct immunofluorescent-antibody assay of tick hemolymph. a comparison o ...19948195390
borrelia burgdorferi antigens that are targeted by antibody-dependent, complement-mediated killing in the rhesus monkey.we identified surface antigens of borrelia burgdorferi that are targeted by antibody-dependent, complement-mediated killing (adck) in the rhesus monkey. for this purpose, we had available serum samples from three animals infected with b. burgdorferi jd1 by needle inoculation and from two monkeys that were infected with the same b. burgdorferi strain by ixodes scapularis tick bite. sera from monkeys from the first group contained antibodies to ospa and ospb detectable by western blot (immunoblot) ...19947927774
competence of dogs as reservoirs for lyme disease spirochetes (borrelia burgdorferi).dogs become infected with borrelia burgdorferi after being bitten by infected adult ticks. however, it is not known whether dogs are competent reservoirs of the organism, that is, it is not known whether infected dogs can subsequently transmit the bacterium to feeding immature ticks. to determine reservoir competence of dogs, 11 beagles were experimentally infected by means of challenge exposure to infected adult deer ticks (ixodes scapularis). three weeks later, larval ticks were allowed to fee ...19947928571
quantitation of the borrelia burgdorferi outer surface protein a in ixodes scapularis: fluctuations during the tick life cycle, doubling times, and loss while feeding.the presence of outer surface protein a (ospa) as a marker for borrelia burgdorferi in ixodes scapularis ticks was monitored with an ospa antigen-capture elisa. the ospa elisa, with a sensitivity of 30 spirochetes (8 fg), was not affected by the presence of either recently blood-fed or flat tick homogenates. median spirochete equivalent levels as high as 16,000 in larvae, 55,000 in attached nymphs, and 10,000 in unfed adults were observed. estimates of ospa doubling times ranged from a maximum o ...19947930731
prevalence of borrelia burgdorferi in host-seeking ticks (acari: ixodidae) from a lyme disease endemic area in northern michigan.the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was recovered from the guts of questing ixodes scapularis say adults and nymphs and adult dermacentor variabilis (say), collected in menominee county, michigan, in 1992. spirochetes were cultured successfully from guts placed in modified barbour-stoenner-kelly ii medium held in 5-ml cultures tubes or in 0.3-ml wells of microtiter plates. most isolates were recovered within 2 wk of culturing at an incu ...19947932597
vector competence of ixodes pacificus and dermacentor occidentalis (acari: ixodidae) for various isolates of lyme disease spirochetes.the vector competence of the western black-legged tick, ixodes pacificus cooley & kohls, and the pacific coast tick, dermacentor occidentalis marx, for the lyme disease spirochete (borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner) was compared. rabbits, hamsters, and the deer mouse, peromyscus maniculatus (wagner), were injected with cultured spirochetes or infected tick-suspensions, or were fed upon by spirochete-infected ticks. five of seven isolates used as inocula were reiso ...19948057316
cytogenetic characteristics of cell lines from ixodes scapularis (acari: ixodidae).three new cell lines, ide8 and ide12 from embryos of northern specimens of ixodes scapularis say and ise18 from southern specimens of i. scapularis, were compared cytogenetically via conventional karyotyping, c- and g-banding, and nucleolar organizing regions (nors). the karyotypes were very similar. the standard karyotype in the three cell lines consisted of 28 chromosomes with 26 autosomes and xx (female) or xy (male) sex chromosomes. the x chromosome was the largest, and the y chromosome the ...19948057317
field trial of an outer surface protein a (ospa) antigen-capture enzyme-linked immunosorbent assay (elisa) to detect borrelia burgdorferi in ixodes scapularis.field-collected adult male ixodes scapularis from westchester county, new york were bisected and borrelia burgdorferi infection rates were ascertained by both a direct fluorescent antibody test and an outer surface protein a (ospa) antigen-capture enzyme-linked immunosorbent assay (elisa). both assays gave identical antigen positivity rates with 89% concordance between the two assays. storing dried ticks before elisa analysis had no significant effect on the ability of the elisa to determine the ...19948147494
cultivation of borrelia burgdorferi from human tick bite sites: a guide to the risk of infection.the risk of acquiring lyme disease has been evaluated by xenodiagnostic procedures with laboratory strains of borrelia burgdorferi and laboratory-reared ixodes ticks, or by clinical trials in which diagnosis was based on clinical findings, culture, or serologic tests.19957829700
determining the duration of ixodes scapularis (acari: ixodidae) attachment to tick-bite victims.the duration of tick attachment is one factor associated with risk for human infection caused by several tick-borne pathogens. we measured tick engorgement indices at known time intervals after tick attachment and used these indices to determine the length of time that ticks were attached to tick-bite victims in selected rhode island and pennsylvania communities where the agents of lyme disease and human babesiosis occur. the total body length and width as well as the length and width of the scu ...19958551509
acquired resistance in dogs to repeated infestation with ixodes scapularis (acari: ixodidae) reduces tick viability and reproductive success.the purpose of this study was to determine whether dogs develop acquired resistance to adult ixodes scapularis infestation in an experimental model. five dogs were each infested with ten mating pairs of ticks every week for 7 consecutive weeks, another five dogs were each infested with ten mating pairs once every 2 weeks for 10 weeks and four dogs served as controls not exposed to ticks. all ticks were allowed to feed to repletion and were collected only after dropping from the host. several var ...19958556959
growth and migration of borrelia burgdorferi in ixodes ticks during blood feeding.we have studied the growth of borrelia burgdorferi in nymphal ticks (ixodes scapularis) feeding on mice using confocal fluorescence microscopy to follow the distribution of spirochetes. in starved nymphs, the bacteria were only detected in the midgut and each nymph had a mean of 496 spirochetes. upon attachment of nymphs to the host, the bacteria grew with a doubling time close to 4 hr and reached a mean of 7,848 spirochetes per nymph 15 hr after attachment. during this initial period (36 hr) of ...19957485694
incomplete protection of hamsters vaccinated with unlipidated ospa from borrelia burgdorferi infection is associated with low levels of antibody to an epitope defined by mab la-2.efforts to develop a recombinant vaccine for lyme disease have focused on using the outer surface protein a (ospa) of borrelia burgdorferi as an immunogen. we evaluated the effectiveness of an unlipidated recombinant ospa as a vaccine in hamsters. this molecule is soluble and can be produced in high yield in escherichia coli, characteristics that permit simple and relatively low cost production. vaccination with unlipidated ospa protected a substantial portion of animals--59-79%, depending on th ...19957491816
reservoir competence of the rice rat (rodentia: cricetidae) for borrelia burgdorferi.the reservoir competence of the rice rat, oryzomys palustris, for borrelia burgdorferi is described. infected ixodes scapularis say (i. dammini, spielman, clifford, piesman & corwin) nymphs were used to infect animals. borrelia infection was diagnosed by xenodiagnostic feeding of noninfected i. scapularis larvae and by reisolation of the spirochetes from blood and other tissues. rice rats acquired b. burgdorferi and maintained spirochete infection for 5-9 wk. b. burgdorferi were cultured from sa ...19957608919
recombinant ospa protects dogs against infection and disease caused by borrelia burgdorferi.twenty-two specific-pathogen-free beagles were vaccinated with recombinant ospa (ospa gene derived from borrelia burgdorferi b31) alone or with adjuvant (quila, montanide isa25, or aluminum hydroxide) at 6 weeks of age. thirteen dogs were used as nonvaccinated controls with or without adjuvant. three dogs were kept as contact controls and received neither vaccine nor challenge. six weeks or 6 months after the first vaccination, the vaccinated (20 of 22) and nonvaccinated dogs (13) were challenge ...19957642289
evaluation of ixodes scapularis, amblyomma americanum, and dermacentor variabilis (acari: ixodidae) from georgia as vectors of a florida strain of the lyme disease spirochete, borrelia burgdorferi.the ability of three common tick species from georgia to maintain and transmit the causative agent of lyme disease, borrelia burgdorferi, was compared under laboratory conditions. a b. burgdorferi cotton rat isolate (mi-6) from florida was selected as a strain from the south, and the sh2-82 isolate from new york was used as a positive control. amblyomma americanum (l.) and dermacentor variabilis (say) did not transmit the mi-6 isolate from inoculated hamsters to naive laboratory mice, and nympha ...19957650697
ticks (acari: ixodidae) infesting wild birds (aves) and white-footed mice in lyme, ct.birds were captured and recaptured (20.8% of 5,297) with japanese mist nets, and white-footed mice, peromyscus leucopus (rafinesque), were caught and recaught (69.1% of 355) with sherman box traps during the late spring, summer, and early fall from july 1989 through october 1991 to study tick-host relationships in lyme, ct. ixodes scapularis say, a vector of lyme disease spirochetes, borrelia burgdorferi sensu stricto johnson, schmid, hye, steigerwalt & brenner, infested 803 birds (15.2%) in 36 ...19957650706
dispersal of the lyme disease spirochete borrelia burgdorferi to salivary glands of feeding nymphal ixodes scapularis (acari: ixodidae).salivary gland explant cultures from 3/16 (19%) of unfed nymphal ixodes scapularis say contained lyme disease spirochetes, increasing to a maximum of 14/16 (88%) at 72 h of tick feeding. homogenates of tick salivary glands did not produce infection in laboratory white mice unless harvested from ticks attached for > or = 60 h. dispersal of spirochetes to the salivary glands appears to occur during the act of tick feeding, thus affecting the ability of ticks to transmit borrelia burgdorferi.19957650714
borrelia burgdorferi in eastern virginia: comparison between a coastal and inland locality.in virginia, borrelia burgdorferi was more prevalent in a site along the atlantic ocean, near maryland, than in an inland site near williamsburg and yorktown. at the coastal site on assateague island, b. burgdorferi was isolated from 4.2% of 475 animals sampled, including four species of small mammals. serologic tests indicated that 25-37% of the small rodents assayed had been exposed to b. burgdorferi. immunofluorescence antibody assays specific for b. burgdorferi showed spirochete infection in ...19957677212
protection of dogs from lyme disease with a vaccine containing outer surface protein (osp) a, ospb, and the saponin adjuvant qs21.a vaccine consisting of purified escherichia coli-expressed recombinant full-length outer surface proteins a (ospa) and b (ospb) and the saponin adjuvant qs21 was evaluated for protection against borrelia burgdorferi infection. eleven beagles were vaccinated twice and then challenged with 10 field-collected adult female ixodes scapularis. xenodiagnosis revealed that all 11 nonvaccinated control dogs and 2 of 10 vaccinated dogs were infected with b. burgdorferi. six of 11 control dogs also develo ...19957706788
molecular typing of borrelia burgdorferi sensu lato by pcr-restriction fragment length polymorphism analysis.the etiologic agent of lyme borreliosis, borrelia burgdorferi sensu lato, has been isolated from many biologic sources in north america and eurasia, and isolates have been divided into three distinct genospecies (b. burgdorferi sensu stricto, borrelia garinii, and borrelia afzelii). in order to explore the possible association of genospecies with disease manifestation, 60 isolates of b. burgdorferi sensu lato were subjected to 5s rdna-linked restriction fragment length polymorphism (rflp) analys ...19957751362
borrelia burgdorferi in an urban environment: white-tailed deer with infected ticks and antibodies.ticks and blood samples were collected from white-tailed deer (odocoileus virginianus) in forests located in an insular, urban area of bridgeport, conn., and in rural south central connecticut during 1992 and 1993. immature and adult ixodes scapularis ticks were tested for borrelia burgdorferi, the etiologic agent of lyme borreliosis, by indirect fluorescent-antibody staining methods. deer sera were analyzed for antibodies to this bacterium by an enzyme-linked immunosorbent assay. infected ticks ...19957751354
chronic lyme disease in the rhesus monkey.we have previously reported the clinical, pathologic, and immunologic features of "early" borrelia burgdorferi infection in rhesus monkeys (3). we have now evaluated these features during the chronic phase of lyme disease in this animal model.19957853849
natural occurrence and characterization of the lyme disease spirochete, borrelia burgdorferi, in cotton rats (sigmodon hispidus) from georgia and florida.this is the first report of natural infection by borrelia burgdorferi in the cotton rat sigmodon hispidus. nine b. burgdorferi isolates were obtained from ear tissues, urinary bladders, or both, by culturing tissues in bskii medium. the rat from which the si-3 isolate was cultured was from the same site (sapelo island, georgia) as an infected cotton mouse peromyscus gossypinus and ixodes scapularis tick reported previously. the 8 b. burgdorferi isolates from rats in florida included 1 (ai-1) fro ...19957876974
suppression of acute ixodes scapularis-induced borrelia burgdorferi infection using tumor necrosis factor-alpha, interleukin-2, and interferon-gamma.down-regulation of mammalian cytokine production has been demonstrated during tick feeding. to examine the hypothesis that reconstitution of cytokines during tick feeding could facilitate immune containment of borrelia burgdorferi, the following experiments were done. c3h/hej mice were given cytokines for 10 days after ixodes scapularis attachment. at day 21, ear biopsies were analyzed for b. burgdorferi. polymerase chain reaction analysis indicated a protection rate of 95% in mice receiving tum ...19968537658
acquired resistance and antibody response of raccoons (procyon lotor) to sequential feedings of ixodes scapularis (acari: ixodidae).captive-bred raccoons (procyon lotor) developed immune resistance to infestation by the larval stage of the ixodid tick, ixodes scapularis, the vector of borrelia burgdorferi, following repeated applications of both nymphs and larvae. resistance was expressed as a significant decrease in the proportion of engorged larvae recovered from each cohort. resistance to nymphs was not noted, but, only two such cohorts were applied. utilizing an enzyme-linked immunosor-bent assay (elisa) developed to det ...19968966995
lyme borreliosis in the southern united states: a review.lyme borreliosis (lyme disease) is the most often reported arthropod transmitted disease in humans in the u.s.a. although it has been reported from 43 states, cases are especially abundant in the mid-atlantic and northeastern regions. borrelia burgdorferi, the etiologic agent, is transmitted primarily by the western blacklegged tick (ixodes pacificus) in far western north america, and by the blacklegged tick (ixodes scapularis) in eastern north america. although lyme disease cases have been repo ...19968973401
safety, efficacy, and immunogenicity of a recombinant osp subunit canine lyme disease vaccine.a subunit canine lyme disease vaccine formulated with recombinant lipidated osp a and ospb and saponin qs21 was assessed for safety, protective efficacy, and immunogenicity. ten normal beagles were subcutaneously vaccinated twice at age 12 and 16 weeks, respectively. three months after the second vaccination, the vaccinates and another 10 nonvaccinated control beagles were challenged by feeding ticks on each dog for 5 days using eight field-collected adult female and six adult male ixodes scapul ...19969004447
population genetics of ixodes scapularis (acari: ixodidae) based on mitochondrial 16s and 12s genes.blacklegged tick, ixodes scapularis say, is the principal vector of borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner in the eastern half of the united states. populations exhibit extreme variation in morphology, host usage, development time, and behavior. we examined sequence variation in the 16s and 12s mitochondrial ribosomal dna genes to determine genetic relationships among i. scapularis collections from throughout its range. single strand conformation polymorphism analysis ...19968906909
ability of experimentally infected chickens to infect ticks with the lyme disease spirochete, borrelia burgdorferi.chickens were used as a laboratory model to determine the conditions affecting the ability of birds to infect ticks with lyme disease spirochetes. chicks (gallus gallus) were exposed to 12 nymphal ixodes scapularis at one week or three weeks of age. xenodiagnostic larval ticks fed these birds at weekly intervals thereafter. chicks exposed to infected nymphs at one week of age infected 87% of larvae at three weeks of age, but only infected 3% of larvae at four weeks and 0% of larvae at five weeks ...19968600769
reservoir competence of the southeastern five-lined skink (eumeces inexpectatus) and the green anole (anolis carolinensis) for borrelia burgdorferi.the reservoir competence of two lizard species, the southeastern five-lined skink (eumeces inexpectatus) and the green anole (anolis carolinesis), for borrelia burgdorferi was evaluated. skinks and anoles were exposed by needle inoculation or tick bite to b. burgdorferi. xenodiagnosis with larval ixodes scapularis and culture of tissues were used to asses infection and the ability of infected lizards to infect attached ticks. both lizard species were susceptible to b. burgdorferi by both routes ...19968651379
role of bird migration in the long-distance dispersal of ixodes dammini, the vector of lyme disease.to evaluate the role of migratory birds in the long-distance dispersal of ixodes dammini ticks and in the spread of lyme disease, a 6-year study of migrating birds to an offshore new england island was conducted during 1989-1994. i. dammini are not endemic on this island, therefore allowing assessment of long-distance tick dispersal rather than local infestation. of 11,324 spring migrants examined, 1.2% were infested with i. dammini. of 8607 fall migrants examined, 0.2% were infested. of nymphal ...19968656000
ixodes (ixodes) scapularis (acari:ixodidae): redescription of all active stages, distribution, hosts, geographical variation, and medical and veterinary importance.the blacklegged tick, ixodes (ixodes) scapularis say, 1821, is redescribed, based on laboratory reared specimens originating in bulloch county, georgia. information on distribution, host associations, morphological variation, and medical/veterinary importance is also presented. a great deal of recent work has focused on this species because it is the principal vector of the agent of lyme disease (borrelia burgdorferi johnson, schmidt, hyde, steigerwaldt & brenner) in eastern north america. its d ...19968667375
lyme disease spirochetes in ticks collected from birds in midwestern united states.in a tick-spirochete survey conducted from all 1989 through fall 1992 in north-western wisconsin, 4,256 birds (composed of 91 species) were examined for ticks. infestations were recorded for 400 birds (composed of 30 species). of 1,184 ticks taken from 335 birds (composed of 26 species), 60 (5%) haemaphysalis leporispalustris (packard) from 8 species of birds were infected with the lyme disease spirochete. borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner. similar surveys conduct ...19968667384
experimental infection of the raccoon (procyon lotor) with borrelia burgdorferi.the reservoir competence of the raccoon (procyon lotor) for the lyme disease spirochete (borrelia burgdorferi) was evaluated in the laboratory during september 1991 to april 1993. five raccoons were exposed to spirochete-infected (jd1 and wisconsin 210 wise strains) ixodes scapularis nymphs (20/raccoon). a second feeding of spirochete-infected (wisconsin 210 wise strain) nymphs (20/raccoon) was performed with four of the original raccoons. xenodiagnosis with cohorts of i. scapularis larvae (300/ ...19968722269
the effect of infection with lyme disease spirochetes (borrelia burgdorferi) on the phototaxis, activity, and questing height of the tick vector ixodes scapularis.little is known about the effects of infection with borrelia burgdorferi, the bacterium that causes lyme disease, on its tick vectors. the purpose of this study was to determine the behavioural and ecological effects of infection by the bacterium in nymphal and adult black-legged (ixodes scapularis) ticks. we found that the effects of infection were more pronounced in adults than in nymphs. compared to uninfected adults, infected adults were less able to overcome physical obstacles, avoided vert ...19968760310
ticks and borrelia: model systems for investigating pathogen-arthropod interactions.blood-feeding arthropods transmit numerous types of infectious agent and parasite that have a tremendous impact on human health and mortality throughout the world. these vector-borne pathogens display a wide array of evolutionary patterns that allow them to infect and to be successfully transmitted by ticks, mites, and hematophagous insects. the vector's method of feeding, type of development, and host preference are also critical factors for the transfer of zoonotic agents from wild animal rese ...19968805079
methods for evaluating lyme disease risks using geographic information systems and geospatial analysis.lyme disease is a tick-transmitted borreliosis of humans and domestic animals emerging as one of the most significant threats to public health in north temperate regions of the world. however, despite a myriad of studies into symptomology, causes, and treatment of the disease, few researchers have addressed the spatial aspects of lyme disease transmission. using statewide data collected in rhode island (united states) as a test case, we demonstrated that exposure to deer ticks and the risk of co ...19968840676
spread of ixodes scapularis (acari:ixodidae) in indiana: collections of adults in 1991-1994 and description of a borrelia burgdorferi-infected population.collection records for the adult black legged tick, ixodes scapularis say, in indiana for the period 1991-1994 are presented and a new, established population of borrelia burgdorferi-infected i. scapularis is described. the number of i. scapularis adults collected in indiana increased progressively from 19 in 1991 to > 200 in 1994, and the number of indiana counties reporting at least 1 adult increased from 13 to 29. also, during this period, 4 countries in northwestern indiana yielded > 10 spec ...19968840696
novel borrelia burgdorferi isolates from ixodes scapularis and ixodes dentatus ticks feeding on humans.seven cultures of borrelia burgdorferi differing from strains b31 and zs7 were identified from among 99 isolates from ixodes scapularis ticks and from white-footed mice (peromyscus leucopus) and 1 isolate from an ixodes dentatus tick. five of the six novel isolates from i. scapularis and the isolate from i. dentatus were from ticks feeding on humans. the six isolates from i. scapularis lacked ospa and ospb, four possessed an ospd band, and two reacted with an anti-ospc monoclonal antibody. restr ...19968904407
multiple infections of ixodes scapularis ticks by borrelia burgdorferi as revealed by single-strand conformation polymorphism analysis.the genetic heterogeneity of the spirochete borrelia burgdorferi within single adult black-legged ticks from shelter island, n.y., was determined by cold, single-strand conformation polymorphism (sscp) analysis. the central region of the ospa gene of b. burgdorferi from infected ticks was amplified by nested pcr. amplified product of the correct size was obtained from 20 to 45 ticks (44%). this is the fraction of ticks that is expected to be infected with b. burgdorferi. four variant classes wer ...19968904432
immunoserologic evidence of coinfection with borrelia burgdorferi, babesia microti, and human granulocytic ehrlichia species in residents of wisconsin and minnesota.in wisconsin and minnesota, ixodes scapularis (ixodes dammini) ticks are the vector of three microorganisms that may cause significant disease in humans and lower mammals. these diseases include lyme borreliosis, which is caused by borrelia burgdorferi, babesiosis, which is caused by babesia microti, and human granulocytic ehrlichiosis (hge), which is caused by an apparently new species in the genus ehrlichia. immunoserologic testing was performed on sera from patients with a diagnosis of one of ...19968904446
borrelia burgdorferi-infected ixodes scapularis (acari: ixodidae) and peromyscus leucopus in northeastern wisconsin.populations of the blacklegged tick, ixodes scapularis say, are established in western and central wisconsin in the upper midwestern united states, but appear to be expanding geographically there. here, we report a previously unknown population in northeastern wisconsin. questing i. scapularis nymphs and adults were collected by flagging vegetation from a riverine site in marinette county, wisconsin, in spring of 1993 and 1994. dissection and culture of tick guts in modified barbour-stoenner-kel ...19968906923
presence of ixodiphagus hookeri (hymenoptera: encyrtidae) in two connecticut populations of ixodes scapularis (acari: ixodidae).two connecticut populations of the black-legged tick, ixodes scapularis (say), the vector of lyme disease spirochetes, borrelia bugrdorferi sensu stricto johnson, schmid, hyde, steigerwalt & brenner, in the northeastern united states, are parasitized by the encyrtid wasp ixodiphagus hookeri (howard), formerly hunterellus hookeri. the wasp was first detected in ticks from a forested site in bridgeport in 1992. i. hookeri was reared from 18.6% of 148 host-seeking i. scapularis nymphs. in 1993 and ...19968906928
resistance to tick-borne spirochete challenge induced by borrelia burgdorferi strains that differ in expression of outer surface proteins.hamsters were immunized with thimerosal-killed borrelia burgdorferi 297 or a mutant of 297 (m297) that lacks the 49-kb linear plasmid and expression of outer surface proteins a and b (ospa and ospb). ixodes scapularis nymphs infected with either the b. burgdorferi sensu stricto strain 297 or jmnt, similar in ospa and ospb but differing in ospc expression, were used to evaluate protection. in a homologous challenge, 24 hamsters were vaccinated, 8 each with 297 or m297 and 8 sham (adjuvant)-vaccin ...19968926082
a case of concurrent lyme meningitis with ehrlichiosis.we report on a case of concurrent lyme meningitis and ehrlichiosis in a patient with occupational exposure to ticks as a logger. the patient had a febrile illness with a reticulate erythematous rash on his upper torso, meningoencephalitis, thrombocytopenia, and hepatitis. acute and convalescent serologies were consistent with a dual infection with lyme disease and ehrlichiosis. ixodes scapularis is the tick that is associated with lyme disease in our area and this tick has also been reported to ...19968953687
absence of lyme disease spirochetes in larval progeny of naturally infected ixodes scapularis (acari:ixodidae) fed on dogs.i determined whether transovarial passage of lyme disease spirochetes occurred more efficiently in ixodes scapularis say fed on reservoir-competent dogs. unlike deerfed ticks, spirochetes are not diminished in dog-fed ticks, and significantly higher transovarial infection rates have been reported for the latter. females of field-infected i. scapularis (north salem strain) were used to induce experimental lyme disease in specific pathogen-free dogs as part of another study. seventy-four (48 of 65 ...19979086711
vector competence of ixodes scapularis, i. spinipalpis, and dermacentor andersoni (acari:ixodidae) in transmitting borrelia burgdorferi, the etiologic agent of lyme disease.this report describes the vector competence of 3 ixodid tick species, ixodes scapularis (say), i. spinipalpis (nuttall), and dermacentor andersoni (stiles), for borrelia burgdorferi in colorado. the study was based on preliminary field work performed in 6 colorado counties, where rodents and ticks were collected and assayed for the presence of b. burgdorferi. four of the 6 counties produced 52 rodent and 39 i. spinipalpis isolates of b. burgdorferi. two b. burgdorferi isolates were tested under ...19979103755
characterization of an immunoreactive protein from the agent of human granulocytic ehrlichiosis.a gene that is homologous to the ehrlichia chaffeensis groel operon was recovered and characterized by broad-range pcr amplification of whole blood from patients with human granulocytic ehrlichiosis (hge) and from infected hl60 cell cultures. sequence analysis of an 820-bp dna fragment recovered directly from human blood showed 76.5 and 76.3% identity with cognate sequences from e. chaffeensis and cowdria ruminantium, respectively. analysis of a 1.6-kb dna fragment derived from an hge agent-infe ...19979114402
inhibition of efficient polymerase chain reaction amplification of borrelia burgdorferi dna in blood-fed ticks.polymerase chain reaction (pcr) analysis is a widely used method for detection of borrelia burgdorferi dna in biological specimens, including ticks. studies have demonstrated that substances present in mammalian blood can inhibit pcr amplification. this would limit the utility of pcr for determination of b. burgdorferi infection in engorged ticks that have taken a blood meal from a human or other animal host. to systematically assess the potential for such inhibition, nymphal ixodes scapularis, ...19979129540
human disease in europe caused by a granulocytic ehrlichia species.human granulocytic ehrlichiosis (hge) was recently described in north america. it is caused by an ehrlichia species closely related to ehrlichia phagocytophila and ehrlichia equi, recognized to infect mostly ruminants and horses, respectively. the vector in north america is the tick ixodes scapularis, which is also the vector of the lyme disease agent, borrelia burgdorferi. previous serologic studies in patients with a diagnosis of lyme borreliosis indicate that hge may exist in europe. we repor ...19979163481
transmission of the agent of human granulocytic ehrlichiosis by host-seeking ixodus scapularis (acari:ixodidae) in southern new york state.ixodes scapularis say nymphs collected from a natural focus of human granulocytic ehrlichiosis (hge) in westchester county, new york, transmitted the hge agent to uninfected mice in the laboratory. infection was demonstrated in 3 of 8 mice by polymerase chain reaction analysis of whole blood and microscopic examination of blood smears for morulae. two of these mice were also positive by xenodiagnosis. positive xenodiagnostic larvae maintained infection through molting and transferred infection t ...19979220669
ability of the lyme disease spirochete borrelia burgdorferi to infect rodents and three species of human-biting ticks (blacklegged tick, american dog tick, lone star tick) (acari:ixodidae).the infectivity of a diverse collection of borrelia burgdorferi strains from north america for mice was determined as a prelude to vector competence experiments with the 3 primary human-biting tick species in the eastern united states (ixodes scapularis say, dermacentor variabilis (say), amblyomma americanum (l.)]. of the 34 b. burgdorferi strains inoculated into mice, 29 were infectious; the exceptions were 5 isolates from texas. vector competence experiments were conducted with 2 strains from ...19979220680
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