Publications

ixodes dammini as a potential vector of human granulocytic ehrlichiosis.	little is known about the epidemiology and mode of transmission of the agent of human granulocytic ehrlichiosis (hge). analyses of an engorged female ixodes dammini tick removed from an hge patient and 101 field-collected i. dammini and dermacentor variabilis from three wisconsin counties for borrelia burgdorferi and ehrlichia phagocytophila/ehrlichia equi dna revealed that the patient tick and 7 of 68 i. dammini ticks from washburn county collected in 1982 and 1991 were positive for ehrlichial ...	1995	7561173
human granulocytic ehrlichiosis in the upper midwest united states. a new species emerging?	to characterize the clinical presentation and course, laboratory findings, and treatment outcome of 12 patients with human granulocytic ehrlichiosis.	1994	8022040
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
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
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
prevalence of granulocytic ehrlichia infection among white-tailed deer in wisconsin.	human granulocytic ehrlichiosis (hge) is caused by an agent that is nearly indistinguishable from the veterinary pathogens ehrlichia equi and ehrlichia phagocytophila. the deer tick, ixodes scapularis, is a vector of the hge agent, and the white-tailed deer is the primary host for adult ixodes ticks. we assessed the distribution of granulocytic ehrlichia infection among deer living within (wisconsin) and outside (western and southern iowa) the geographic range of l. scapularis. whole-blood sampl ...	1997	9163463
serologic evidence of infection with ehrlichia spp. in wild rodents (muridae: sigmodontinae) in the united states.	rodent (muridae: sigmodontinae) blood and sera collected from 14 states were tested for seroreactivity to a cultured isolate of the human granulocytic ehrlichiosis (hge) agent by using an indirect immunofluorescence assay. of the 1,240 samples tested, 136 (11%) were found to be reactive at titers of > or = 32. rodents with hge agent-specific antibodies were found in new york (23% of 491 samples; geometric mean endpoint titer [gmt] = 441), connecticut (11% of 100 samples; gmt = 481), california ( ...	1998	9508298
serologic evidence of a natural infection of white-tailed deer with the agent of human granulocytic ehrlichiosis in wisconsin and maryland.	white-tailed deer participate in the maintenance of the ixodes tick life cycle and are reservoirs for some tick-borne infectious agents. deer may be useful sentinels for tick-transmitted agents, such as ehrlichiae. in order to determine whether white-tailed deer are markers of natural transmission or are reservoirs for the human granulocytic ehrlichiosis (hge) agent, we performed indirect immunofluorescent-antibody (ifa) tests and immunoblotting with the hge agent and ehrlichia chaffeensis on se ...	1998	9801331
seroprevalence of human granulocytic ehrlichiosis among permanent residents of northwestern wisconsin.	four-hundred seventy-five permanent residents of wisconsin were tested for antibodies to the agent of human granulocytic ehrlichiosis (hge) by indirect immunofluorescent antibody (ifa) testing with ehrlichia equi as antigen marker. each resident completed a standard survey questionnaire about outdoor activities, animal and tick exposure, and any febrile illness during the preceding 12 months. seventy-one serum samples (14.9%) contained e. equi antibodies. the mean ifa titer for seropositive resi ...	1998	9868666
serologic testing for human granulocytic ehrlichiosis at a national referral center.	an indirect immunofluorescence assay (ifa) was used to identify patients with antibodies reactive to the human granulocytic ehrlichiosis (hge) agent. serum samples collected from clinically ill individuals were submitted to the centers for disease control and prevention by physicians via state health departments from throughout the united states and tested against a panel of ehrlichial and rickettsial pathogens. antibodies reactive to the hge agent were detected in 142 (8.9%) of 1,602 individual ...	1999	9986812
ehrlichia equi infection of horses from minnesota and wisconsin: detection of seroconversion and acute disease investigation.	equine granulocytic ehrlichiosis (ege) is caused by infection with ehrlichia equi. ege has been reported primarily in northern california, where e equi is transmitted by the tick ixodes pacificus. reports of ege and the emergence of human granulocytic ehrlichia in minnesota prompted a seroprevalence study of e equi in horses of minnesota and wisconsin. tick (ixodes scapularis) endemic areas of minnesota and wisconsin were compared to nonendemic regions of minnesota. indirect fluorescent antibody ...	2000	10830537
tickborne infections as a cause of nonspecific febrile illness in wisconsin.	lyme disease, human granulocytic ehrlichiosis (hge), and babesiosis are tickborne infections that are indigenous to wisconsin. to assess their importance as a cause of nonspecific fever, we recruited patients with febrile illness at 10 clinics in northwestern wisconsin from may through august of both 1997 and 1998. eligible patients had a temperature >38.0 degrees c but no rash or other localizing source. acute and convalescent serological tests were performed for borrelia burgdorferi, babesia m ...	2001	11317244
seroprevalence of antibodies that react with anaplasma phagocytophila, the agent of human granulocytic ehrlichiosis, in different populations in westchester county, new york.	we determined the frequencies of antibodies to anaplasma phagocytophila, the agent of human granulocytic ehrlichiosis (hge), in different groups of adults and children from westchester county, new york. the groups included 159 adult blood donors and 215 children who were seronegative for borrelia burgdorferi antibodies, 118 adult patients and 57 children who were seropositive for b. burgdorferi antibodies, and 42 adult patients with culture-confirmed erythema migrans. eighteen (11.3%) of the blo ...	2002	12089287
relationship between tick bites and the seroprevalence of babesia microti and anaplasma phagocytophila (previously ehrlichia sp.) in blood donors.	tick-borne diseases, particularly babesiosis and ehrlichiosis, represent recently emerging infections. despite an increased recognition of the threat tick-borne agents pose to blood safety, our understanding of the prevalence and transmissibility of these agents in blood donors is limited.	2002	12473139
antibiotic susceptibilities of anaplasma (ehrlichia) phagocytophilum strains from various geographic areas in the united states.	we tested the antibiotic susceptibilities of eight strains of anaplasma phagocytophilum (the agent of human granulocytic ehrlichiosis) collected in various geographic areas of the united states, including minnesota, wisconsin, california, and new york. the results are homogeneous and show that doxycycline, rifampin, and levofloxacin are the most active antibiotics against these strains in vitro.	2003	12499227
importance of primer specificity for pcr detection of anaplasma phagocytophila among ixodes scapularis ticks from wisconsin.		2003	12904445
presence of borrelia burgdorferi (spirochaetales: spirochaetaceae) in southern kettle moraine state forest, wisconsin, and characterization of strain w97f51.	lyme disease, caused by borrelia burgdorferi johnson, schmidt, hyde, steigerwalt & brenner; babesiosis, caused by babesia microti franca; and human granulocytic ehrlichiosis, caused by anaplasma phagocytophilum bakken & dumler have been reported in wisconsin, mainly in the endemic areas of the northwestern part of the state. people exposed to blacklegged ticks, ixodes scapularis say, from this region can potentially contract one or all of these diseases concurrently. within the past several year ...	2005	15962800
anaplasma phagocytophilum in central and western wisconsin: a molecular survey.	anaplasma phagocytophilum is an obligate intracellular bacterium that is transmitted to humans through the bite of ixodes spp. ticks, and causes a febrile disease known as human granulocytic anaplasmosis. the presence of a. phagocytophilum in wisconsin white-tailed deer blood and in deer ticks was assessed using pcr and dna sequencing. sampling sites in the western part of the state (buffalo county) and central region (waushara, waupaca, and green lake counties) were used. in buffalo county, 5.6 ...	2006	16738890
infection and co-infection rates of anaplasma phagocytophilum variants, babesia spp., borrelia burgdorferi, and the rickettsial endosymbiont in ixodes scapularis (acari: ixodidae) from sites in indiana, maine, pennsylvania, and wisconsin.	in total, 394 questing adult blacklegged ticks, ixodes scapularis say (acari: ixodidae), collected at four sites were analyzed by polymerase chain reaction (pcr) for five microbial species: anaplasma phagocytophilum, babesia microti, babesia odocoilei, borrelia burgdorferi, and the rickettsial i. scapularis endosymbiont. identities of genetic variants of a. phagocytophilum were determined by sequencing a portion of the 16s dna. in 55% of infected ticks (193/351), a single agent was detected. in ...	2008	18402145
anaplasma phagocytophilum infection in dogs: 34 cases (2000-2007).	objective- to determine demographic characteristics of dogs from the upper midwest infected with anaplasma phagocytophilum and identify clinical and clinicopathologic abnormalities and response to treatment. design- retrospective case series and owner telephone survey. animals- 34 dogs with granulocytic anaplasmosis. procedures- records were reviewed for information on signalment, history, physical examination findings, clinicopathologic and serologic findings, and treatment. owners were contact ...	2009	19527130
rhabdomyolysis-induced acute kidney injury secondary to anaplasma phagocytophilum and concomitant statin use.	we report the case of a patient with rhabdomyolysis-induced acute renal failure occurring in the setting of anoplasma phagocytophilum infection based on the presence of morulae in neutrophils and concomitant statin use. although the pathogenesis is unknown, we believe the combination of concurrent statin use in the setting of the infection promoted this complication. we describe proposed mechanisms including cytokine activation, alteration of the muscle membrane components, and ionic balance as ...	2011	21560563
Expansion of the Midwestern focus for human granulocytic anaplasmosis into the region surrounding La Crosse, Wisconsin.	Anaplasma phagocytophilum, the causative agent of human granulocytic anaplasmosis (HGA), shares the same enzootic life cycle as Borrelia burgdorferi, the causative agent of Lyme disease. Although La Crosse, WI, is a well-recognized Lyme disease focus with an abundance of Ixodes scapularis vector ticks and the first documentation of HGA occurred in patients from northwestern Wisconsin, local transmission of A. phagocytophilum has not to date been documented. In this study, we evaluated DNA extrac ...	2011	21918026
prevalence of borrelia burgdorferi and anaplasma phagocytophilum in ixodes scapularis (acari: ixodidae) nymphs collected in managed red pine forests in wisconsin.	changes in the structure of managed red pine forests in wisconsin caused by interacting root- and stem-colonizing insects are associated with increased abundance of the blacklegged tick, ixodes scapularis say, in comparison with nonimpacted stands. however, the frequency and variability of the occurrence of tick-borne pathogens in this coniferous forest type across wisconsin is unknown. red pine forests were surveyed from 2009 to 2013 to determine the prevalence of borrelia burgdorferi and anapl ...	2014	24897864
human infection with ehrlichia muris-like pathogen, united states, 2007-2013(1).	an ehrlichia muris-like (eml) pathogen was detected among 4 patients in minnesota and wisconsin during 2009. we characterized additional cases clinically and epidemiologically. during 2004-2013, blood samples from 75,077 patients from all 50 united states were tested by pcr from the groel gene for ehrlichia spp. and anaplasma phagocytophilum. during 2007-2013, samples from 69 (0.1%) patients were positive for the eml pathogen; patients were from 5 states: indiana (1), michigan (1), minnesota (33 ...	2015	26402378
prevalence and distribution of human and tick infections with the ehrlichia muris-like agent and anaplasma phagocytophilum in wisconsin, 2009-2015.	ehrlichiosis and anaplasmosis are important emerging tickborne zoonoses that affect both humans and animals. knowledge of the geographic distribution and prevalence of ehrlichia spp. and anaplasma phagocytophilum in wisconsin is important information as a baseline for future comparisons. reported human cases between 2009 and 2015 were identified using the wisconsin electronic disease surveillance system (wedss) and mapped by county of residence. vector surveillance was established using ticks co ...	2017	28055326