scholarly journals Granulocytic Ehrlichiosis in Tick-Immune Guinea Pigs

1998 ◽  
Vol 66 (4) ◽  
pp. 1803-1805 ◽  
Author(s):  
Subrata Das ◽  
Kathleen Deponte ◽  
Nancy L. Marcantonio ◽  
Jacob W. Ijdo ◽  
Emir Hodzic ◽  
...  
Keyword(s):  
Lyme Borreliosis ◽  
Guinea Pigs ◽  
Ixodes Scapularis ◽  
Host Immunity ◽  
Granulocytic Ehrlichiosis ◽  
Human Granulocytic Ehrlichiosis

ABSTRACT We investigated whether Ixodes scapularis-mediated host immunity interrupts transmission of the agent of human granulocytic ehrlichiosis (aoHGE) to guinea pigs. Ticks infected with aoHGE readily transmitted aoHGE to tick-immune guinea pigs, despite incomplete tick engorgement and host attachment. Although tick immunity can prevent Lyme borreliosis, protection is not afforded against granulocytic ehrlichiosis.

Simultaneous Human Granulocytic Ehrlichiosis and Lyme Borreliosis

1997 ◽  
Vol 337 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Robert B. Nadelman ◽  
Harold W. Horowitz ◽  
Tze-chen Hsieh ◽  
Joseph M. Wu ◽  
Maria E. Aguero-Rosenfeld ◽  
...  
Keyword(s):  
Lyme Borreliosis ◽  
Granulocytic Ehrlichiosis ◽  
Human Granulocytic Ehrlichiosis

scholarly journals Human Granulocytic Ehrlichiosis Agent Infection in a Pony Vaccinated with a Borrelia burgdorferi Recombinant OspA Vaccine and Challenged by Exposure to Naturally Infected Ticks

2000 ◽  
Vol 7 (1) ◽  
pp. 68-71 ◽  
Author(s):  
Yung-Fu Chang ◽  
Sean P. McDonough ◽  
Chao-Fu Chang ◽  
Kwang-Soon Shin ◽  
William Yen ◽  
...  
Keyword(s):  
Borrelia Burgdorferi ◽  
Inclusion Bodies ◽  
Ixodes Scapularis ◽  
Clinical Signs ◽  
Buffy Coat ◽  
The Body ◽  
Granulocytic Ehrlichiosis ◽  
Flunixin Meglumine ◽  
Human Granulocytic Ehrlichiosis ◽  
Vector Dna

ABSTRACT A pony was vaccinated with recombinant OspA vaccine (rOspA) and then exposed 3 months later to Borrelia burgdorferi-infected ticks (Ixodes scapularis) collected in Westchester County, N.Y. At 2 weeks after tick exposure, the pony developed a high fever (105°F). Buffy coat smears showed that 20% of neutrophils contained ehrlichial inclusion bodies (morulae). Flunixin Meglumine (1 g daily) was given for 2 days, and the body temperature returned to normal. PCR for ehrlichial DNA was performed on blood samples for 10 consecutive days beginning when the pony was first febrile. This pony was monitored for another 3.5 months but developed no further clinical signs. The 44-kDa immunodominant human granulocytic ehrlichiosis antigen gene was amplified by PCR and cloned into a pCR2.1 vector. DNA sequence analysis of this gene showed it was only 8 bp different (99% identity) from the results reported by others (J.W. Ijdo et al., Infect. Immun. 66:3264–3269, 1998). Western blot analysis, growth inhibition assays, and repeated attempts to isolate B. burgdorferi all demonstrated the pony was protected against B. burgdorferi infection. These results highlight the potential for ticks to harbor and transmit several pathogens simultaneously, which further complicates the diagnosis and vaccination of these emerging tick-borne diseases.

scholarly journals Low rates of ehrlichiosis and Lyme borreliosis in English farmworkers

1998 ◽  
Vol 121 (3) ◽  
pp. 609-614 ◽  
Author(s):  
D. Rh. THOMAS ◽  
M. SILLIS ◽  
T. J. COLEMAN ◽  
S. M. KENCH ◽  
N. H. OGDEN ◽  
...  
Keyword(s):  
Rural Communities ◽  
Lyme Borreliosis ◽  
Companion Animals ◽  
Tick Bites ◽  
Serological Evidence ◽  
Granulocytic Ehrlichiosis ◽  
Human Granulocytic Ehrlichiosis ◽  
History Of ◽  
Delays In Diagnosis ◽  
Human Monocytic Ehrlichiosis

To determine the occupational significance of tick-borne zoonoses we sought serological evidence of Lyme borreliosis, human monocytic ehrlichiosis (HME) and human granulocytic ehrlichiosis (HGE) in a representative sample of farmworkers. Although around 20% reported ticks on their domestic and companion animals, few (<2% per year) reported being bitten by ticks. Seroprevalence of Lyme borreliosis (0·2%), HME (0·2%) and HGE (1·5%) was low. Those seropositive for HGE were no more likely to report tick bites nor more likely to report ticks on their animals. This study provides evidence that farmworkers in England are exposed to tick-borne zoonoses but that they are uncommon. Since the severity of these diseases is linked to delays in diagnosis and treatment, clinicians should be aware of these diagnoses in patients from rural communities, with or without a self-reported history of tick bite.

scholarly journals Acquisition of Coinfection and Simultaneous Transmission of Borrelia burgdorferi and Ehrlichia phagocytophila by Ixodes scapularis Ticks

2000 ◽  
Vol 68 (4) ◽  
pp. 2183-2186 ◽  
Author(s):  
Michael L. Levin ◽  
Durland Fish
Keyword(s):  
Lyme Disease ◽  
Borrelia Burgdorferi ◽  
Ixodes Scapularis ◽  
The Other ◽  
Infection Status ◽  
Granulocytic Ehrlichiosis ◽  
Ehrlichia Phagocytophila ◽  
Human Granulocytic Ehrlichiosis ◽  
Previous Infection ◽  
Prior Infection

ABSTRACT The agents of Lyme disease (Borrelia burgdorferi) and human granulocytic ehrlichiosis (Ehrlichia phagocytophila) are both transmitted by the tick Ixodes scapularis. In nature, ticks are often infected with both agents simultaneously. We studied whether previous infection with either Borrelia orEhrlichia in ticks would affect acquisition and transmission of a second pathogen. Ehrlichia-infectedI. scapularis nymphs were fed uponBorrelia-infected mice, and Borrelia-infectedI. scapularis nymphs were fed uponEhrlichia-infected mice. The efficiency with which previously infected nymphal ticks acquired a second pathogen from infected hosts was compared to that of uninfected ticks. An average of 51% ± 15% of ticks acquired Ehrlichia from infected mice regardless of their prior infection status with Borrelia. An average of 85% ± 10% of ticks acquired Borrelia from infected mice regardless of their prior infection status withEhrlichia. Also, we assessed the efficiency with which individual nymphs could transmit either agent alone, or both agents simultaneously, to individual susceptible hosts. An average of 76% ± 9% of Borrelia-infected ticks and 84% ± 10% ofEhrlichia-infected ticks transmitted these agents to mice regardless of the presence of the other pathogen. There was no evidence of interaction between the agents of Lyme disease and human granulocytic ehrlichiosis in I. scapularis ticks. The presence of either agent in the ticks did not affect acquisition of the other agent from an infected host. Transmission of the agents of Lyme disease and human granulocytic ehrlichiosis by individual ticks was equally efficient and independent. Dually infected ticks transmitted each pathogen to susceptible hosts as efficiently as ticks infected with only one pathogen.

scholarly journals Molecular Cloning and Sequencing of Three Granulocytic Ehrlichia Genes Encoding High-Molecular-Weight Immunoreactive Proteins

1998 ◽  
Vol 66 (4) ◽  
pp. 1356-1363 ◽  
Author(s):  
James R. Storey ◽  
Linda A. Doros-Richert ◽  
Cindy Gingrich-Baker ◽  
Kenneth Munroe ◽  
Thomas N. Mather ◽  
...  
Keyword(s):  
Genomic Library ◽  
Ixodes Scapularis ◽  
Pcr Primers ◽  
16S Rdna Sequence ◽  
Granulocytic Ehrlichiosis ◽  
Human Granulocytic Ehrlichiosis ◽  
Vaccine Antigens ◽  
Genes Encoding ◽  
Molecular Masses

ABSTRACT Granulocytic Ehrlichia was isolated from canine blood obtained from animals challenged with field-collected Ixodes scapularis and propagated in HL60 cells. PCR primers specific for the 16S ribosomal DNA (rDNA) of the Ehrlichia genogroup comprising E. equi, E. phagocytophila, and the agent of human granulocytic ehrlichiosis (HGE) amplified DNA from extracts of these cells. Sequence analysis of this amplified DNA revealed that it is identical to the 16S rDNA sequence of the HGE agent. A genomic library was constructed with DNA from granulocyticEhrlichia and screened with pooled sera from tick-challenged, granulocytic Ehrlichia-infected dogs. Several clones were isolated and sequenced. Three complete genes encoding proteins with apparent molecular masses of 100, 130, and 160 kDa were found. The recombinant proteins reacted with convalescent-phase sera from dogs and human patients recovering from HGE. This approach will be useful for identifying candidate diagnostic and vaccine antigens for granulocytic ehrlichiosis and aid in the classification of genogroup members.

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