Publications

a case of ehrlichia equi in an adult horse in british columbia.		1996	8681291
the first isolation, in vitro propagation, and genetic characterization of ehrlichia canis in israel.	ehrlichia canis, the etiologic agent of canine ehrlichiosis, was isolated in israel from a naturally infected dog with acute signs of the disease. the organism designated e. canis 611, was passaged experimentally to a beagle, from which it was propagated in primary canine monocytes. the organism was then grown in vitro in a continuous canine cell line, dh82. nine beagles subsequently injected with whole e. canis-infected blood all developed typical symptoms of ehrlichiosis. an indirect immunoflu ...	1996	8686178
human ehrlichiosis in the united states.		1996	8714253
tick-borne illness increasing in oklahoma.		1996	8720556
ehrlichial infections.		1996	8727132
laboratory diagnosis of rickettsial diseases.		1996	8727134
survey of ehrlichia canis antibodies among dogs in israel.	a seroepidemiological survey was made of the prevalence of antibodies reactive with ehrlichia canis in stray and pet dogs from five geographical regions of israel. serum samples from 410 dogs were assayed by an indirect fluorescent antibody test and serum reactive at a 1:20 dilution or greater was considered positive. the overall seroprevalence was 30 per cent with 23.9 per cent in pet dogs and 37.5 per cent in stray dogs. the seroprevalence in apparently healthy pets (17.6 per cent) was lower b ...	1996	8734508
isolation of ehrlichia canis from dogs following subcutaneous inoculation.	subcutaneous inoculation of dogs with ehrlichia canis was investigated as a more appropriate model of canine ehrlichiosis, which is naturally transmitted by arthropod vectors. a dose-dependent response occurred following subcutaneous inoculation of seven groups of dogs with log concentrations of e. canis-infected canine-origin cells. ehrlichial infection in dogs was defined as concurrence of an increased titer of anti-e. canis immunoglobulin g (igg) antibody in serum, a decreased platelet concen ...	1996	8735093
antibodies in cat sera from southern africa react with antigens of ehrlichia canis.		1996	8737264
canine infectious cyclic thrombocytopenia found in taiwan.	here were report the first canine infectious cyclic thrombocytopenia (cict) found in taiwan. platelet-specific inclusions were detected in the blood smear of a military working dog. to identify the etiologic agent, the patient's blood was transmitted to three six-month-old german shepherd dogs. the ehrlichia platys-like inclusions were observed six to eight days after inoculation. indirect fluorescent antibody test showed that the serum from the patient reacted specifically with the microorganis ...	1996	8741613
geographic, clinical, serologic, and molecular evidence of granulocytic ehrlichiosis, a likely zoonotic disease, in minnesota and wisconsin dogs.	seventeen minnesota and wisconsin dogs with granulocytic ehrlichosis were studied. the diagnoses were made by finding ehrlichia morulae in peripheral blood neutrophils. eight dogs were studied retrospectively, and nine dogs were studied prospectively. the medical records of all dogs were reviewed. eighty-eight percent of the dogs were purebred and 76% were spayed females. the median age was 8 years. sixty-five percent of the cases were diagnosed in october and november. fever and lethargy were t ...	1996	8748270
demonstration of vertical transmission of cowdria ruminantium, the causative agent of heartwater, from cows to their calves.	one of the most important questions about the epidemiology of heartwater in the field is how cowdria ruminatium is transmitted within vertebrate host populations. in this study vertical transmission of c. ruminantium from cows to their calves was demonstrated. twelve mixed-breed calves, born to dams living in a heartwater-endemic area of zimbabwe, were tested post-natally for the presence of c. ruminantium. vertical transmission was demonstrated to occur under natural field conditions using test ...	1996	8750689
colostrum from dams living in a heartwater-endemic area influences calfhood immunity to cowdria ruminantium.	two studies were carried out to determine whether colostrum from dams living in a heartwater-endemic area has an influence on calfhood immunity to cowdria ruminantium infection. the initial study was conducted using friesian calves originating from a heartwater-free herd. experimental groups consisted of calves receiving colostrum from dams living in a heartwater-endemic area and known to be exposed to c. ruminantium (as determined by the indirect fluorescent antibody test) and calves receiving ...	1996	8750690
[the brown dog tick, rhipicephalus sanguineus (ixodidae), in germany: an epidemiologic study and control measures].	between january and december 1995 infestations with rhipicephalus sanguineus were established in 22 dogs in germany. out of these 22 animals 2 originated from the endemic area of this tick species, spain and the dominican republic and 11 dogs accompanied their owner to the mediterranean countries, 5 to italy, 3 to france, 2 to spain and 1 animal to greece. six dogs had never left germany and with 3 dogs the way of infestation could not be reconstructed. in 16 cases an abundant occurrence of r. s ...	1996	8765542
progress and priorities in research on heartwater.		1996	8784481
uncharacterized ehrlichia spp. may contribute to clinical heartwater.		1996	8784482
amino acid and protein depletion in medium of cell cultures infected with cowdria ruminantium.	cowdria ruminantium (rickettsiales) causes heartwater in ruminants of africa, and some islands off africa and in the caribbean sea. the in vitro culture method for the organism devised in 1985, which provided for the first time a means for production of adequate quantities of live organisms and their products, is erratic and requires improvement. we studied depletion of amino acids (aas) and major proteins in culture medium taken daily from infected and uninfected ovine and bovine vascular endot ...	1996	8784483
recombinant expression and use in serology of a specific fragment from the cowdria ruminantium map1 protein.	the major antigenic protein (map1) of cowdria ruminantium was screened for immunogenic regions by expression of overlapping recombinant dna clones of the gene encoding the map1 protein. two regions, designated map1-a and map1-b, were recognized by all antisera to 9 different isolates of c. ruminantium. map1-a contained one or more epitopes responsible for false-positive reactions with ehrlichia antisera in several serological tests for cowdriosis. cross-reactivity with map1-b was limited to anti ...	1996	8784484
genetic resistance of creole goats to cowdriosis in guadeloupe. status in 1995.	a genetic predisposition to resistance (r)/susceptibility (s) has been demonstrated for cowdriosis in certain goal lines. in order to identify genetic markers of r/s and to follow their transmission to the offspring, 4 groups of sires and dams were crossbred in 1991, 1992, and 1993: rr, rs, sr, and ss. the offspring were challenged at the age of six months with subsequent challenge of the s parent. from 28 presumed s dams, 7 turned out r and from 2 presumed s sires, 1 was r and the other undefin ...	1996	8784485
artificial feeding systems for ixodid ticks as a tool for study of pathogen transmission.		1996	8784502
evaluation of anaplasma marginale major surface protein 3 (msp3) as a diagnostic test antigen.	an immunodominant surface protein, major surface protein 3 (msp3), has been proposed as an antigen suitable for use in the diagnosis of bovine anaplasmosis. we further characterized msp3 to examine its potential as a test antigen for the serological diagnosis of carrier cattle. the specificity of this antigen in detecting infected cattle as well as the conservation of msp3 between strains of anaplasma marginale was evaluated by using immunoblots of a. marginale proteins separated by one- and two ...	1996	8788999
equine granulocytic ehrlichiosis in connecticut caused by an agent resembling the human granulocytotropic ehrlichia.	the first recognized cases of equine granulocytic ehrlichiosis in new england are described. the dna sequence of the 16s rrna gene of the causative ehrlichia was found to be identical to that of the human granulocytotropic ehrlichia, the agent of human granulocytic ehrlichiosis.	1996	8789032
serosurvey for cowdria ruminantium, coxiella burnetii, and spotted fever group rickettsiae in ostriches (struthio camelus) from zimbabwe.	sera from 216 ostriches on nine farms around zimbabwe were examined by indirect fluorescent antibody (ifa) testing for the presence of antibodies reactive with cowdria ruminantium, coxiella burnetii, and rickettsia africae, a spotted fever group rickettsia. although no reactive antibodies could be detected to c. ruminantium or c. burnetii, 51/216 (35%) sera reacted with r. africae. the seroprevalence in ostriches from the south of zimbabwe was significantly higher than in birds from the north (p ...	1996	8790897
kinetics of serum antiplatelet antibodies in experimental acute canine ehrlichiosis.	the pattern of appearance of serum antiplatelet antibodies during the acute phase of experimental canine ehrlichiosis (ehrlichia canis) was investigated in six beagles and correlated with the development of thrombocytopenia. the earliest detection of serum antiplatelet antibodies was made on day 7 post-inoculation in one dog, on day 13 in three out of six dogs, and on day 17 post-inoculation in the remaining two dogs. thrombocytopenia developed in all infected dogs. the results of this study sug ...	1996	8797272
sequence heterogeneity of the major antigenic protein 1 genes from cowdria ruminantium isolates from different geographical areas.	the genes for the immunodominant major antigenic protein 1 (map1) of cowdria ruminantium from four african and two caribbean isolates were cloned, restriction mapped, and sequenced to identify conserved epitopes for development of serodiagnostic tools for heartwater. restriction length polymorphisms were observed among the respective map1 genes analyzed and were confirmed by sequencing. the sequence data generated for these isolates were compared with data for the previously reported senegal iso ...	1996	8807206
heartwater in ghana: implications for control of ticks.	heartwater, an often fatal rickettsial disease of domestic ruminants transmitted by amblyomma variegatum ticks, ranks with the a. variegatum-associated skin disease dermatophilosis as a major constraint to the upgrading of livestock productivity in ghana. an epidemiological survey, using new diagnostic tests, is being carried out to determine the incidence and distribution of heartwater and other tickborne diseases in ghanaian cattle, sheep and goats. preliminary results from a longitudinal surv ...	1996	8809994
the control of heartwater in west africa--present and future.	heartwater (hw) is the name given to the acute, febrile disease of ruminants caused by infection with the obligate intra-cellular rickettsia cowdria ruminantium. the effect of losses associated with hw and dermatophilosis are an important constraint to the sustainable use of non-indigenous breeds, but recent advances in heartwater and dermatophilosis research provide optimism that integrated control of these conditions can be achieved in west africa. the relevant advances in hw research are in m ...	1996	8809995
exposure to deer blood may be a cause of human granulocytic ehrlichiosis.		1996	8816164
necrotizing enterocolitis in horses: a retrospective study.	the clinical and clinicopathologic characteristics of fatal necrotizing enterocolitis were examined in 16 horses (age 4 months to 12 years). at initial presentation, 8 of 16 horses were pyrexic (median temperature, 38.4 degrees c; range, 33.8 to 40.6 degrees c); all 16 were tachycardic (median heart rate, 93 bpm, range, 66 to 138 bpm); 13 of 16 were tachypneic (median heart rate, 36 bpm, range, 16 to 80 bpm), dehydrated, and had discolored mucous membranes. all horses that were pyrexic were also ...	1996	8819053
post-therapy antibody titers in dogs with ehrlichiosis: follow-up study on 68 patients treated primarily with tetracycline and/or doxycycline.	the clinical and serological responses to therapy were evaluated for at least 1 year in 68 dogs with antibody titers positive for ehrlichia canis. treatments were of variable periods with primarily tetracycline hydorchloride and/or doxycycline. sixteen dogs had initial titers of 1:20 and, at the end of the year, were asymptomatic, no longer receiving medication, and had negative serology. the average length of treatment with tetracycline hcl and/or doxycycline was 85 days (range, 14 to 360 days) ...	1996	8819054
a recombinant antigen from the heartwater agent (cowdria ruminatium) reactive with antibodies in some southeastern united states white-tailed deer (odocoileus virginianus), but not cattle, sera.	recombinant baculovirus techniques were used to express the 260 amino acid carboxyterminal portion of the 32 kilodalton (kda) major antigenic protein (map 1) of cowdria ruminantium, the heartwater agent, as a fusion protein. the recombinant map 1 was fused to an aminoterminal independently antigenic octapeptide sequence (flag peptide). recombinant map 1 was used as an immunoblotting antigen to evaluate numerous reference antisera against organisms of the tribe ehrlichieae. monoclonal and polyclo ...	1996	8827667
polymerase chain reaction evidence of ehrlichia chaffeensis, an etiologic agent of human ehrlichiosis, in dogs from southeast virginia.	to ascertain whether dogs are naturally infected with ehrlichia chaffeensis.	1996	8836370
central nervous system manifestations of human ehrlichiosis.	since 1989, we have confirmed the diagnosis of human ehrlichiosis in 57 patients. although routine radiological studies of the central nervous system (cns) or analyses of cerebrospinal fluid (csf) samples were not done for these patients, primary care physicians detected symptoms or signs that prompted them to perform such studies. csf samples were examined for 15 of the 57 patients. findings in eight of the 15 csf samples were abnormal, and the most common abnormalities were lymphocytic pleocyt ...	1996	8842270
specific, nonradioactive detection of the nhp bacterium in penaeus vannamei by in situ hybridization.	necrotizing hepatopancreatitis (nhp) is a disease of farm-raised pacific white shrimp (penaeus vannamei) caused by a pleomorphic intracellular bacterium. a dna probe that is specific for the etiologic agent of necrotizing hepatopancreatitis was devised and tested in an in situ hybridization assay. a procedure was developed for labeling a single-stranded dna probe with digoxigenin by the polymerase chain reaction. the dna probe encompasses the v1 and v2 variable regions of the 16s ribosomal rna ( ...	1996	8844575
from the centers for disease control and prevention. human ehrlichiosis--maryland, 1994.		1996	8849737
ehrlichia equi infection associated with rhabdomyolysis.		1996	8853010
heartwater in sheep and goats: a review.	heartwater (cowdriosis) is an important, often fatal, tick-borne disease of domestic and wild ruminants in sub-saharan africa and some indian ocean and caribbean islands. the causal agent, cowdria ruminantium (cowdry 1925), is a rickettsia closely related to members of the genus ehrlichia, and is probably a part of a complex of genomic species. imported breeds of sheep and goats (especially angoras) are highly susceptible, but indigenous populations of endemic areas may be resistant to infection ...	1996	8856765
ehrlichia canis-like agent isolated from a man in venezuela: antigenic and genetic characterization.	we report the first isolation and molecular and antigenic characterization of a human ehrlichial species in south america. a retrospective study was performed with serum specimens from 6 children with clinical signs suggestive of human ehrlichiosis and 43 apparently healthy adults who had a close contact with dogs exhibiting clinical signs compatible with canine ehrlichiosis. the evaluation was performed by the indirect fluorescent-antibody assay with ehrlichia chaffeensis arkansas, ehrlichia ca ...	1996	8862572
a 16s rrna-based pcr assay for detection and identification of granulocytic ehrlichia species in dogs, horses, and cattle.	a pcr-based assay was developed for detecting dna of granulocytic ehrlichiae in blood samples from dogs, horses, and cattle, primers were designed from 16s rrna sequence information to specifically amplify dna from a newly identified swedish ehrlichia species. the 16s rrna nucleotide sequence of this swedish species differs in only two and three positions from the sequences of ehrlichia phagocytophila and ehrlichia equi, respectively, which were also amplified by this pcr system. for evaluation, ...	1996	8862579
human granulocytic ehrlichiosis: report of a case in northern california.		1996	8879806
impaired antigen specific responses and enhanced polyclonal stimulation in mice infected with ehrlichia muris.	the immune status of balb/c mice infected by intraperitoneal inoculation with ehrlichia muris was examined. the level of e. muris infection in both peritoneal cavity and spleen was greatest at day 10 postinoculation (pi). thereafter, the infection level was dramatically reduced while the organism persisted for up to 400 days pi. the greatest intraperitoneal infiltration of leukocytes, splenomegaly, and leukocytosis were observed on days 10, 15, and 20 pi, respectively. infected mice developed ma ...	1996	8887352
platelet dysfunction associated with experimental acute canine ehrlichiosis.	to determine whether platelet dysfunction occurs in canine ehrlichiosis, platelet aggregation studies in response to collagen/epinephrine, thrombin and adenosine diphosphate (adp) were carried out by the indirect method, using sera from six dogs experimentally infected with ehrlichia canis. samples of serum taken before infection and four and 20 days after infection were tested by incubation with platelet-rich plasma from a seronegative healthy dog. platelet aggregation was significantly inhibit ...	1996	8890464
the recombinant 120-kilodalton protein of ehrlichia chaffeensis, a potential diagnostic tool.	dna encoding two repeat units of 120-kda protein of ehrlichia chaffeensis was cloned into the expression vector pgex and expressed in escherichia coli. the sensitivity and specificity of a dot blot assay for detection of human antibodies with the recombinant protein were 86 and 100%, respectively, compared with an indirect immunofluorescence assay.	1996	8897200
human ehrlichiosis.	human ehrlichiosis is a newly emergent, tick-borne, zoonotic infection caused by members of the genus ehrlichia. these rickettsia-like, obligate intracellular, gram-negative bacteria produce two similar yet distinct diseases. human monocytic ehrlichiosis is caused by ehrlichia chaffeensis. human granulocytic ehrlichiosis is caused by an organism closely related to ehrlichia equi. the most common initial clinical findings include fever, malaise, myalgia, headaches and rigors, while the most commo ...	1996	8900357
lyme disease and ehrlichiosis.	this article provides the podiatric practitioner with current information about lyme disease and ehrlichlosis. the material presented assists podiatrists, particularly those practicing in rural areas, in recognizing these tick-bone diseases and in making informed decisions about treatment. the steady increase of these "new and emerging infectious diseases" places additional importance on health care providers, such as podiatrists, to inform the public and help prevent the incidences of tick born ...	1996	8902334
emergence of the ehrlichioses as human health problems.	ehrlichiae are small, gram-negative, obligately intracellular bacteria that reside within a phagosome. the first human ehrlichial infection was recognized in the united states in 1987. it was later shown to be caused by a new species, ehrlichia chaffeensis. in 1994, an ehrlichial pathogen within neutrophils that is closely related to the known veterinary pathogens e. equi and e. phagocytophila was found to infect humans. molecular methods were required to detect, characterize, and identify these ...	1996	8903194
isolation of the equine granulocytic ehrlichiosis agent, ehrlichia equi, in tick cell culture.	the equine granulocytic ehrlichiosis agent, ehrlichia equi, is closely related or identical to the human granulocytic ehrlichiosis (hge) agent. both are suspected of being transmitted by ticks. we have successfully isolated e. equi in a cell line, ide8, derived from a putative vector, the tick ixodes scapularis. peripheral blood leukocytes from an experimentally infected horse were inoculated onto ide8 monolayers. cultures were incubated in a candle jar at 34 degrees c in tick cell culture mediu ...	1996	8904434
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 ...	1996	8904446
ehrlichia platys infection in dogs.		1996	8905592
ixodes pacificus (acari: ixodidae) as a vector of ehrlichia equi (rickettsiales: ehrlichieae).	ehrlichia equi, a rickettsia described from horses in california 30 yr ago, causes equine granulocytic ehrlichiosis throughout the americas and possibly europe. here, we report experimental transmission of e. equi from infected to susceptible horses through bites of western blacklegged ticks, ixodes pacificus (cooley & kohls). in preliminary field studies, only i. pacificus consistently infested horses and vegetation at 3 locations with contemporary cases of equine ehrlichosis, and in particular ...	1996	8906897
site-specific geographic association between amblyomma americanum (acari: ixodidae) infestations and ehrlichia chaffeensis-reactive (rickettsiales: ehrlichieae) antibodies in white-tailed deer.	serum samples from white-tailed deer, odocoileus virginianus zimmermann, collected from 1982 through 1992 from the southeastern united states were tested for antibodies reactive to ehrlichia chaffeensis anderson, dawson, jones, & wilson, the causative agent of human ehrlichiosis. results were compared between areas based on known infestations of the lone star tick, amblyomma americanum l., a suspected vector of e. chaffeensis. one hundred and twenty-five of 300 (41.7%) deer tested positive (> or ...	1996	8906920
a case of concurrent presentation of human ehrlichiosis and lyme disease in connecticut.	this is a case of a long-term connecticut resident who presented with both human granulocytic ehrlichiosis and lyme disease. the etiologic agents and the probability of coinfection are discussed.	1996	8908776
persistent infection of c3h/hej mice by ehrlichia chaffeensis.	description of the pathobiology of the recently described zoonotic agent of human ehrlichiosis (ehrlichia chaffeensis) would be greatly facilitated by the availability of a convenient experimental animal model of infection. we determined whether c3h/hej mice could sustain persistent infection by this predominantly monocyte-inhabiting rickettsia. such mice rapidly produced an intense specific igg response upon inoculation of ehrlichiae, and high titers were demonstrable for more than 6 months the ...	1996	8914255
attempted transmission of ehrlichia canis by rhipicephalus sanguineus after passage in cell culture.	to compare the transmissibility by the brown dog tick, rhipicephalus sanguineus, of a recent isolate of ehrlichia canis (ebony) with that of another isolate (oklahoma) that had been passaged in cell culture, and to assess the genetic similarity of the 2 isolates as reflected in the nucleotide (nt) sequence of 16s rdna.	1996	8915436
[human ehrlichiosis: report of the 1st case in venezuela].	human ehrlichiosis is a zoonotic disease, caused by a rickettsia that infects leukocytes. it was described for the first time in the united states of america in 1986. more than 300 cases have been reported in that country. one case has been reported in portugal, two in france and one more in a tourist coming from mali (africa). in venezuela, a tropical country, where ehrlichiosis is endemic in dogs and horses, the first case of human ehrlichiosis is reported in a seventeen month old girl. she in ...	1996	8920030
absence of tumor necrosis factor alpha, interleukin-6 (il-6), and granulocyte-macrophage colony-stimulating factor expression but presence of il-1beta, il-8, and il-10 expression in human monocytes exposed to viable or killed ehrlichia chaffeensis.	ehrlichia chaffeensis is a recently isolated minute gram-negative obligatory intracellular bacterium of monocytes/macrophages and is the etiologic agent of human monocytic ehrlichiosis. it is not known how macrophages respond when they encounter ehrlichiae in terms of cytokine production. in this study, we examined cytokine mrna expression by incubating e. chaffeensis with thp-1 cells and performing competitive reverse transcription-pcr (rt-pcr). at 2 h postinfection, the levels of interleukin-1 ...	1996	8926090
human ehrlichiosis--maryland, 1994.	ehrlichiosis is an emerging tickborne infectious disease caused by obligate intracellular, gram-negative rickettsia that infect leukocytes. human monocytic ehrlichiosis (hme) is caused by ehrlichia chaffeensis and is believed to be transmitted by amblyomma americanum (the lone star tick). most hme cases have been reported in southeastern and south-central states. during may-july 1994, five cases of serologically confirmed hme were identified among residents of maryland. all five persons lived ne ...	1996	8926996
specific amplification of ehrlichia platys dna from blood specimens by two-step pcr.	a two-step pcr method for diagnosis of canine infectious cyclic thrombocytopenia was established. three primers derived from the 16s and rrna gene sequence were used to amplify genomic dna specifically from ehrlichia platys. two-round amplification with dna templates prepared from e. platys-infected blood specimens produced 742- and 385-bp fragments, but these products were not found when an ehrlichia canis-infected blood sample and escherichia coli were used. this method, for which the minimum ...	1996	8940461
recombinant bovine interferon gamma inhibits the growth of cowdria ruminantium but fails to induce major histocompatibility complex class ii following infection of endothelial cells.	recombinant bovine ifn gamma is a potent inhibitor of cowdria ruminantium growth in vitro irrespective of the rickettsial stock, or the origin of the endothelial cells. these results suggest an important role for ifn gamma in protective immune responses against c. ruminantium infections. here we also show that ifn gamma can induce the expression of mhc class ii molecules on the surface of endothelial cells. however, treatment of endothelial cells with ifn gamma following infection with cowdria f ...	1996	8941969
serological evidence of human granulocytic ehrlichiosis in norway.	human granulocytic ehriichoisis was first described in 1994. this tick-transmitted illness is increasingly recognized in the usa as well as in europe in areas where ixodes ticks and lyme borreliosis are endemic. blood samples from 58 norwegian patients with physician-diagnosed lyme borreliosis were examined for the presence of antibodies to ehrlichia equi, a surrogate marker of the agent of human granulocytic ehrlichiosis. the results indicated that 10.2% of the patients may have been co-infecte ...	1996	8950565
pcr detection of acute ehrlichia canis infection in dogs.	a polymerase chain reaction (pcr)-based detection assay that specifically detected ehrlichia canis in dogs with acute infections was developed. a region of the 16s ribosomal rna gene of e. canis was targeted for pcr amplification and chemiluminescent hybridization (ch) with a complementary internal 287-base pair (bp) oligonucleotide probe. the ch improved the pcr assay sensitivity 1,000-fold as compared with visualization on ethidium bromide-stained agarose gels. the pcr assay with ch (pcr/ch) d ...	1996	8953528
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 ...	1996	8953687
epitope mapping by expression of restriction enzyme or pcr fragments in bacterial plasmids.		1996	8959723
nested polymerase chain reaction for detection of ehrlichia equi genomic dna in horses and ticks (ixodes pacificus).	a nested polymerase chain reaction for detecting ehrlichia equi in horses and ticks (ixodes pacificus) was developed. a major second-round pcr product of 928 bp could be readily visualized in ethidium bromide-stained agarose minigels. an internal probe was used to verify the identity of the amplified product by non-radioactive (digoxigenin-based) southern blotting; additional confirmation was provided by dna sequence analysis. a dilution study testing the sensitivity of the pcr indicated that dn ...	1996	8966998
detection of ehrlichial antigen in plasma of beagle dogs with experimental acute ehrlichia canis infection.	six beagles were experimentally infected with ehrlichia canis. all dogs developed typical clinical signs of ehrlichiosis and sero-converted. ehrlichial antigenemia in the plasma of the infected dogs was detected using a sandwich enzyme-linked immunosorbent assay (elisa). ehrlichial antigen was present starting 15-20 days post-infection, after the development of clinical signs and antibody titre to ehrlichia canis. the appearance of ehrlichial antigen in the plasma for a relatively short and vari ...	1996	8966999
human granulocytic ehrlichiosis: a case series from a medical center in new york state.	human granulocytic ehrlichiosis (hge) is a newly described illness with few reports in the literature.	1996	8967671
human granulocytic ehrlichiosis in wisconsin and minnesota: a frequent infection with the potential for persistence.	human granulocytic ehrlichiosis (hge) is a tickborne illness caused by an agent closely related to ehrlichia equi and ehrlichia phagocytophila. the clinical presentation is nonspecific, and diagnosis is made infrequently. sixty-six sera were obtained from 54 patients in minnesota and wisconsin with undifferentiated fever during the summer and fall of 1993. serologic reactivity with e. equi was observed in 6 (11%), including 4 seroconversions, 1 stable titer, and 1 seroreversion. of the seroposit ...	1996	8603945
clinical and laboratory characteristics of human granulocytic ehrlichiosis.	to characterize the clinical and laboratory features observed in patients with human granulocytic ehrlichiosis (hge) and evaluate the utility of the diagnostic tools used to confirm the diagnosis.	1996	8604172
analysis and ultrastructural localization of ehrlichia chaffeensis proteins with monoclonal antibodies.	ehrlichia chaffeensis, an obligately intracellular bacterium with tropism for monocytes, is the etiologic agent of human monocytic ehrlichiosis. to determine the nature and ultrastructural location of e. chaffeensis antigens, monoclonal antibodies (mabs) to e. chaffeensis were developed. the mabs were used for immunofluorescence and western immunoblotting analysis of the antigens of density gradient-purified ehrlichiae. monoclonal antibody 6a1 recognized an epitope of a 30-kd protein. this antib ...	1996	8615456
apoptosis of gamma/delta t cells in human ehrlichiosis.	expansion of activated t cells expressing the t-cell receptor (tcr) gamma/delta, cd45ro, and hla-dr antigens is a prominent feature of acute infection with ehrlichia chaffeensis in humans. the fate of these activated cells and the resolution of the gamma/delta t-cell response with return to the usual alpha/beta t-cell populations in this disease are not clearly understood. at a morphologic level, apoptotic cells are present in the peripheral blood during the acute and resolution phases of the in ...	1996	8623774
ehrlichia-like 16s rdna sequence from wild white-tailed deer (odocoileus virginianus).	the reservoir hosts of ehrlichia chaffeensis, etiologic agent of human ehrlichiosis are unknown. initially, white-tailed deer (wtd) were serologically implicated as possible reservoirs of e. chaffeensis. subsequent studies showed that wtd were susceptible to infection with e. chaffeensis and that deer-to-deer transmission by a tick vector, amblyomma americanum, is possible under experimental conditions. to determine if wild wtd were infected with e. chaffeensis, whole blood was collected from 10 ...	1996	8627501
evaluation of vaccination of horses as a strategy to control equine monocytic ehrlichiosis.	to determine whether preferentially vaccinated horses were at risk for exposure to ehrlichia risticii, whether horses with equine monocytic ehrlichiosis (eme) were likely to have been nonvaccinated, and whether clinical severity and financial costs associated with care and treatment of eme were less for vaccinated horses with eme than for nonvaccinated horses with eme.	1996	8635974
integrated tick and tick-borne disease control trials in crossbred dairy cattle in malawi.	crossbred dairy heifers on a farm in an east coast fever (ecf) endemic area in malawi were immunised against theileria parva, anaplasma spp., babesia bigemina, babesia bovis and cowdria ruminantium. they were treated at infrequent intervals with chlorfenvinphos to limit infestation with adult ticks, without providing complete tick control. in one trial, which tested a threshold dipping regimen, 20 heifers were dipped only once in 6 months to control a flush of boophilus microplus. unimmunised co ...	1996	8983132
abortion in a heifer associated with the intra-uterine transmission of cowdria ruminantium-like organisms following heartwater vaccination.	a nguni heifer aborted a 6-month-old foetus 35 days after intravenous inoculation with onderstepoort heartwater vaccine. histopathological examination of the brain revealed numerous suspected cowdria ruminantium organisms in the endothelial cells of the blood vessels. the organisms were ultrastructurally and immunohistochemically compatible with cowdria ruminantium, although, owing to autolysis and cross-reactions, the possibility that they represent another rickettsial or related organism could ...	1996	9120863
evaluation of an improved pcr diagnostic assay for human granulocytic ehrlichiosis.	background: human granulocytic ehrlichiosis (hge) is a tick-borne disease caused by an agent similar to ehrlichia equi. the etiologic agent has only recently been cultivated, and clinical and laboratory findings are nonspecific. severity and fatal outcome are associated with delays in diagnosis and therapy. methods and results: the sensitivity of the polymerase chain reaction (pcr) technique for hge was enhanced at least 250-fold for identification of the 16s ribosomal rna gene of the hge agent ...	1996	10330196
direct cultivation of the causative agent of human granulocytic ehrlichiosis.	human granulocytic ehrlichiosis is a potentially fatal tick-borne infection that has recently been described. this acute febrile illness is characterized by myalgias, headache, thrombocytopenia, and elevated serum aminotransferase levels. the disease is difficult to diagnose because the symptoms are non-specific, intraleukocytic inclusions (morulae) may not be seen, and the serologic results are often initially negative. little is known about the causative agent because it has never been cultiva ...	1996	8531996
ehrlichiosis--in pursuit of an emerging infection.		1996	8532005
ehrlichia infection as a cause of severe respiratory distress.		1996	8532017
the interface between research and the diagnosis of an emerging tick-borne disease, human ehrlichiosis due to ehrlichia chaffeensis.	two new ehrlichial species that cause human disease have recently been identified: ehrlichia chaffeensis and the currently unnamed agent of human granulocytic ehrlichiosis. our objective was to review data on the clinical presentation, laboratory and epidemiological findings, therapy, and diagnostic procedures of patients with human ehrlichiosis due to e chaffeensis. from 1986 through 1994, 400 case patients were identified from 30 us states. most patients had a nonspecific illness, characterize ...	1996	8546547
addressing the challenges of emerging infectious disease.	through the recent examples of diphtheria in the former soviet union, plague in india, and trends in pneumonia mortality in the united states, the author, in this article, illustrates issues in emerging infectious diseases. the centers for disease control's plan, addressing emerging infectious disease threats: a prevention strategy for the united states, is summarized. initial efforts to implement this plan are described, with particular focus on the development of emerging infections programs, ...	1996	8571983
characterization of the sf agent, an ehrlichia sp. isolated from the fluke stellantchasmus falcatus, by 16s rrna base sequence, serological, and morphological analyses.	the organism designated the sf agent was originally isolated in japan in 1962 from stellantchasmus falcatus metacercaria parasitic on gray mullet fish. the sf agent resembles members of the genus ehrlichia morphologically and exhibits weak antigenic cross-reactivity with ehrlichia sennetsu. this organism causes mild clinical signs in dogs, but severe splenomegaly and lymphadenopathy in mice. this suggests that the sf agent may be similar to either neorickettsia helminthoeca, an intracellular par ...	1996	8573488
in vitro isolation and cultivation of cowdria ruminantium under serum-free culture conditions.	three stocks of cowdria ruminantium, the causative agent of heartwater in domestic ruminants, were propagated in bovine endothelial cells in a serum-free culture medium. the vosloo, welgevonden and senegal stocks were propagated for a period of more than 203, 134, and 43 days, respectively. two of the c ruminantium stocks (vosloo and senegal) were also successfully initiated under serum-free culture conditions. the serum-free medium consisted of a modified hl-1 medium. the senegal stock was succ ...	1997	9429251
emerging pathogens associated with tick-borne infections.	in recent years, several microbial agents have been identified that result in significant morbidity and mortality. the newly recognized tick borne infections, babesiosis and ehrlichiosis, may be transmitted by the same tick that transmits borrelia burgdorferi and simultaneous infections may occur. babesia are intraerythrocytic protozoa that may cause severe hemolytic anemia, whereas ehrlichia, depending on the species, may infect either monocytes or granulocytes, with associated leukopenia, thro ...	1997	11107234
cellular changes and induction of apoptosis in human promyelocytic hl-60 cells infected with the agent of human granulocytic ehrlichiosis (hge).	human granulocytic ehrlichiosis (hge) is an emerging and occasionally fatal human infectious disease whose pathogenesis is largely unknown. goodman et al. (1) recently described the successful cultivation of the hge infectious agent in human promyelocytic hl-60 leukemic cells. it was reported in the same study that infectivity invariably led to host cell death, although the mechanism by which hge infection triggers cellular self-destruction is as yet undetermined. in this communication, we show ...	1997	9125168
ehrlichiosis with systemic sepsis syndrome.	the diversity of presenting symptoms with ehrlichia infections makes diagnosis difficult. rash is infrequent. a febrile illness in the summer with thrombocytopenia should arouse suspicion of possible ehrlichiosis.	1997	9130874
development and use of specific polymerase reaction for the detection of an organism resembling ehrlichia sp. in white-tailed deer.	the role of white-tailed deer (odocoileus virginianus) in the epidemiology of ehrlichia chaffeensis and the agent of human granulocytic ehrlichiosis (hge) is not fully understood, and diagnostic procedures may be complicated by the recent detection of 16s rdna sequence from an ehrlichia sp.-like organism in wild deer. a specific forward primer (dga) and an ehrlichia spp. reverse primer (ga1ur) were constructed to amplify this new, distinct ehrlichia sp.-like 16s rdna. the dga primer, a forward p ...	1997	9131554
ultrastructural and antigenic characterization of a granulocytic ehrlichiosis agent directly isolated and stably cultivated from a patient in new york state.	a human granulocytic ehrlichiosis (hge) agent with 16s rdna sequence identical to the published sequence of hge agents was isolated from a patient from new york state by inoculation of the blood leukocyte fraction directly into a human promyelocytic leukemia cell line hl-60. the hge agent was also isolated from the leukocyte fraction of the blood and bone marrow of a mouse inoculated with the leukocyte fraction of the patient's blood. the isolate has been passaged in tissue culture 30 times over ...	1997	8985223
isolation of the causative agent of heartwater (cowdria ruminantium) from three amblyomma species in eight districts of kenya.	thirteen isolates of cowdria ruminantium were made from eight different districts of kenya by four different isolation methods. feeding adult amblyomma species ticks derived from nymphs collected in the field and the inoculation of homogenates prepared from adult field ticks had the highest success rate. the reattachment of adult ticks collected in the field was successful on only one of five attempts, and the subinoculation of blood from suspected heartwater carriers was unsuccessful. seven of ...	1997	9004475
ehrlichia chaffeensis inclusions are early endosomes which selectively accumulate transferrin receptor.	ehrlichia chaffeensis is an obligatory intracellular bacterium which infects macrophages and monocytes. double immunofluorescence labeling was used to characterize the nature of e. chaffeensis inclusion in the human promyelocytic leukemia cell line thp-1. e. chaffeensis was labeled with dog anti-e. chaffeensis serum and fluorescein isothiocyanate-conjugated anti-dog immunoglobulin g (igg). lissamine rhodamine-conjugated anti-mouse igg was used to label various mouse monoclonal antibodies. ehrlic ...	1997	9119487
dogs infected with a human granulocytotropic ehrlichia spp. (rickettsiales: ehrlichieae).	dogs were found to be susceptible to human granulocytotropic ehrlichia spp. infection was produced through the bite of ixodes scapularis say (= dammini spielman, clifford, piesman & corwin) nymphs and adults that acquired infection while feeding as larvae on experimentally infected mice. dogs were also infected by intravenous injection of mouse blood or dog blood from parasitemic donors. parasites were demonstrable in neutrophils within 8 or 9 d after nymphs began feeding; prepatent periods were ...	1997	9439127
[serologic studies on the occurrence of bovine ehrlichiosis in the cantons zürich, schaffhausen, thurgau, st. gallen and obwalden].	the purpose of this study was to investigate the geographical distribution of bovine ehrlichiosis in the cantons zürich, schaffhausen, thurgau, st. gallen and obwalden. to this end, an indirect immunofluorescence assay was established. the diagnostic sensitivity and specificity was estimated to be close to 100% based on the results obtained with several reference sera from the us national veterinary services laboratories and the seroconversion panels of 20 heifers and cows. blood samples from 25 ...	1997	9451917
[tropical animal and human rickettsial infections].	advances in molecular biology have provided tools that have greatly clarified our knowledge of rickettsial diseases. most rickettsias have been reclassified in the alpha subgroup of proteobacteria. four groups of rickettsias have been identified: the spotted fever group, the typhus group, ehrlichia, and bartonella. although still considered as a rickettsia, coxiella burnetti, the agent causing q fever, has been reclassified separately in the gamma subdivision of proteobacteria. recognition of ri ...	1997	9513175
conventional vaccines for tick-borne haemoparasitic diseases of sheep and goats.	of the many tick-borne haemoparasites of sheep and goats, three may be controlled by vaccination. a live virulent blood vaccine for cowdria ruminantium infection (heartwater) is used widely in southern africa in an infection and treatment procedure. a live vaccine for babesia ovis attenuated by passage in splenectomised sheep has been used extensively in bulgaria with good results. a live vaccine for theileria hirci, consisting of schizonts propagated in a lymphoid cell culture and attenuated by ...	1997	9530695
subunit vaccines for the control of tick-borne diseases: implications for the future.	tick-borne parasites are a major constraint to the improvement of livestock productivity in the developing world. these parasites include theileria parva, t. annulata, babesia bigemina, b. bovis, anaplasma marginale and cowdria ruminantium. the impact of these diseases is currently limited by the use of acaricides to decrease transmission by the tick vectors and immunization of the host animals using live vaccines. the use of acaricide is hampered by the development of acaricide resistance and l ...	1997	9530697
erythema migrans-like rash illness at a camp in north carolina: a new tick-borne disease?	borrelia burgdorferi, the causative agent of lyme disease, has never been isolated from a patient thought to have acquired lyme disease in any southeastern state.	1997	9531233
morphological evidence for infection of impala, aepyceros melampus, platelets by a rickettsia-like organism.	ultrastructural studies revealed the presence of a parasite, believed to be ehrlichia platys, in the blood platelets of impala. at the time of blood sampling all the animals appeared healthy. this is the first report on the presence of this rickettsia in these animals, previously described in canine platelets.	1997	9551485
analysis of t-cell responses in cattle immunized against heartwater by vaccination with killed elementary bodies of cowdria ruminantium.	cattle were successfully immunized against heartwater with a lysate of cowdria ruminantium formulated in freund's adjuvant. vaccinated animals proved fully resistant to virulent challenge 3 and 10 months after vaccination. for the first time a helper t lymphocyte response to cowdria antigens was observed and characterized. cowdria-specific t-cell lines generated from vaccinated animals by in vitro restimulation with cowdria lysates are 95 to 100% cd4+, are mhc class ii restricted, and produce ga ...	1997	8975917
isolation and characterization of ehrlichia chaffeensis strains from patients with fatal ehrlichiosis.	two new isolates of ehrlichia chaffeensis (designated jax and st. vincent) were obtained from patients with fatal ehrlichial infections. patients developed characteristic manifestations of severe disease due to e. chaffeensis, including marked thrombocytopenia, pulmonary insufficiency, and encephalopathy. primary isolation was achieved in dh82 cells; the jax and st. vincent isolates were detected within 19 and 8 days postinoculation, respectively. the isolates were characterized by molecular eva ...	1997	9316896
comparison of major antigenic proteins of six strains of the human granulocytic ehrlichiosis agent by western immunoblot analysis.	the etiologic agent of human granulocytic ehrlichiosis (hge) is an obligate intracellular bacterium. in 1996, blood specimens from 53 patients suspected of having hge were examined by indirect fluorescent antibody (ifa) testing with the hge agent no. 13 isolate as the antigen, by nested pcr, and by culture. all patients resided in westchester county, n.y. twelve patient specimens were positive for ifa (titer > or = 1:40). seven of these were also positive by pcr. of the seven specimens positive ...	1997	9316916
antigenic diversity of granulocytic ehrlichia isolates from humans in wisconsin and new york and a horse in california.	the agent of human granulocytic ehrlichiosis (hge), ehrlichia phagocytophila, and ehrlichia equi are very similar. hge is of variable severity. genetic and antigenic differences among 3 human isolates (webster, spooner, and ny-8) and 1 horse isolate (mrk) were evaluated. the 16s rrna gene sequences were identical in all human isolates. by use of 5 homologous antisera from these 3 humans and 1 horse and an additional 5 antisera in heterologous reactions, the immunodominant antigens of each isolat ...	1997	9333162