The Experts below are selected from a list of 11844 Experts worldwide ranked by ideXlab platform

Edward B Breitschwerdt - One of the best experts on this subject based on the ideXlab platform.

  • Candidatus Bartonella merieuxii, a Potential New Zoonotic Bartonella Species in Canids from Iraq
    PLOS Neglected Tropical Diseases, 2012
    Co-Authors: Bruno B Chomel, Rickie W Kasten, Matthew J. Stuckey, Audrey C. Mcmillan-cole, Shingo Sato, Soichi Maruyama, Pedro Paulo Vissotto De Paiva Diniz, Edward B Breitschwerdt
    Abstract:

    Bartonellae are emerging vector-borne pathogens infecting erythrocytes and endothelial cells of various domestic and wild mammals. Blood samples were collected from domestic and wild canids in Iraq under the United States Army zoonotic disease surveillance program. Serology was performed using an indirect immunofluorescent antibody test for B. henselae, B. clarridgeiae, B. vinsonii subsp. berkhoffii and B. bovis. Overall seroprevalence was 47.4% in dogs (n=97), 40.4% in jackals (n=57) and 12.8% in red foxes (n=39). Bartonella species DNA was amplified from whole blood and representative strains were sequenced. DNA of a new Bartonella species similar to but distinct from B. bovis, was amplified from 37.1% of the dogs and 12.3% of the jackals. B. vinsonii subsp. berkhoffii was also amplified from one jackal and no Bartonella DNA was amplified from foxes. Adjusting for age, the odds of dogs being Bartonella PCR positive were 11.94 times higher than for wild canids (95% CI: 4.55–31.35), suggesting their role as reservoir for this new Bartonella species. This study reports on the prevalence of Bartonella species in domestic and wild canids of Iraq and provides the first detection of Bartonella in jackals. We propose Candidatus Bartonella merieuxii for this new Bartonella species. Most of the Bartonella species identified in sick dogs are also pathogenic for humans. Therefore, seroprevalence in Iraqi dog owners and bacteremia in Iraqi people with unexplained fever or culture negative endocarditis requires further investigation as well as in United States military personnel who were stationed in Iraq. Finally, it will also be essential to test any dog brought back from Iraq to the USA for presence of Bartonella bacteremia to prevent any accidental introduction of a new Bartonella species to the New World.

  • Experimental Infection of Horses with Bartonella henselae and Bartonella bovis
    Journal of Veterinary Internal Medicine, 2012
    Co-Authors: J. Palmero, Henrijean Boulouis, Edward B Breitschwerdt, Rickie W Kasten, Natalie A Cherry, Nicola Pusterla, Samantha Mapes, Bruno B Chomel
    Abstract:

    Background Experimental infection of horses with Bartonella species is not documented. Objectives Determine clinical signs, hematologic changes, duration of bacteremia, and pattern of seroconversion in Bartonella henselae or Bartonella bovis-inoculated horses. Animals Twelve (2 groups of 6) randomly selected healthy adult horses seronegative and culture negative for Bartonella spp. Methods Experimental/observational study: Group I: B. henselae or saline control was inoculated intradermally into 4 naive and 2 sentinel horses, respectively. Group II: same design was followed by means of B. bovis. Daily physical examinations, once weekly CBC, immunofluorescent antibody assay serology, real-time polymerase chain reaction (PCR), and twice weekly blood cultures were performed for 6 weeks and at postinoculation day 80 and 139. Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment blood culture was performed for horses that seroconverted to B. henselae antigens. Results Transient clinical signs consistent with bartonellosis occurred in some Bartonella-inoculated horses, but hematological alterations did not occur. Three B. henselae-inoculated horses seroconverted, whereas 1 B. bovis-inoculated horse was weakly seropositive. In Group I, B. henselae was amplified and sequenced from BAPGM blood culture as well as a subculture isolate from 1 horse, blood from a 2nd horse, and BAPGM blood culture from a 3rd horse although a subculture isolate was not obtained. All sentinels remained PCR, culture, and serology negative. Conclusions Detection of Bartonella sp. in blood after experimental inoculation supports bacteremia and seroconversion. Culture with BAPGM may be required to detect Bartonella sp. Although mild clinical signs followed acute infection, no long-term effects were noted for 2 years postinoculation.

  • molecular and serological diagnosis of Bartonella infection in 61 dogs from the united states
    Journal of Veterinary Internal Medicine, 2011
    Co-Authors: Cristina Perez, Ricardo G Maggi, Pedro Paulo Vissotto De Paiva Diniz, Edward B Breitschwerdt
    Abstract:

    Molecular diagnosis of canine bartonellosis can be extremely challenging and often requires the use of an enrichment culture approach followed by PCR amplification of bacterial DNA. HYPOTHESES: (1) The use of enrichment culture with PCR will increase molecular detection of bacteremia and will expand the diversity of Bartonella species detected. (2) Serological testing for Bartonella henselae and Bartonella vinsonii subsp. berkhoffii does not correlate with documentation of bacteremia. ANIMALS: Between 2003 and 2009, 924 samples from 663 dogs were submitted to the North Carolina State University, College of Veterinary Medicine, Vector Borne Diseases Diagnostic Laboratory for diagnostic testing with the Bartonella α-Proteobacteria growth medium (BAPGM) platform. Test results and medical records of those dogs were retrospectively reviewed. METHODS: PCR amplification of Bartonella sp. DNA after extraction from patient samples was compared with PCR after BAPGM enrichment culture. Indirect immunofluorescent antibody assays, used to detect B. henselae and B. vinsonii subsp. berkhoffii antibodies, were compared with PCR. RESULTS: Sixty-one of 663 dogs were culture positive or had Bartonella DNA detected by PCR, including B. henselae (30/61), B. vinsonii subsp. berkhoffii (17/61), Bartonella koehlerae (7/61), Bartonella volans-like (2/61), and Bartonella bovis (2/61). Coinfection with more than 1 Bartonella sp. was documented in 9/61 dogs. BAPGM culture was required for PCR detection in 32/61 cases. Only 7/19 and 4/10 infected dogs tested by IFA were B. henselae and B. vinsonii subsp. berkhoffii seroreactive, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs were most often infected with B. henselae or B. vinsonii subsp. berkhoffii based on PCR and enrichment culture, coinfection was documented, and various Bartonella species were identified. Most infected dogs did not have detectable Bartonella antibodies.

  • Molecular Evidence of Perinatal Transmission of Bartonella vinsonii subsp. berkhoffii and Bartonella henselae to a Child
    Journal of Clinical Microbiology, 2010
    Co-Authors: Edward B Breitschwerdt, Ricardo G Maggi, Peter Farmer, Patricia E. Mascarelli
    Abstract:

    Bartonella vinsonii subsp. berkhoffii, Bartonella henselae, or DNA of both organisms was amplified and sequenced from blood, enrichment blood cultures, or autopsy tissues from four family members. Historical and microbiological results support perinatal transmission of Bartonella species in this family. It is of clinical relevance that Bartonella spp. may adversely influence human reproductive performance.

  • Infection and replication of Bartonella species within a tick cell line
    Experimental and Applied Acarology, 2009
    Co-Authors: Sarah A. Billeter, Edward B Breitschwerdt, Pedro Paulo V. P. Diniz, James M. Battisti, Ulrike G. Munderloh, Michael G Levy
    Abstract:

    Bartonella species are fastidious, gram negative bacteria, some of which are transmitted by arthropod vectors, including fleas, sandflies, and lice. There is very little information regarding the interaction and/or transmission capabilities of Bartonella species by ticks. In the present study, we demonstrate successful infection of the Amblyomma americanum cell line, AAE12, by seven Bartonella isolates and three Candidatus Bartonella species by electron or light microscopy. With the exception of Bartonella bovis , infection with all other examined Bartonella species induced cytopathic effects characterized by heavy cellular vacuolization and eventually cell lysis. Furthermore, using quantitative real time PCR (qPCR), we demonstrated significant amplification of two B. henselae genotype I isolates in the A. americanum cell line over a 5 days period. Ultimately, tick-cell derived Bartonella antigens may prove useful for the development of more sensitive diagnostic reagents and may assist in the development of an effective vaccine to prevent the further spread of disease caused by these organisms.

Didier Raoult - One of the best experts on this subject based on the ideXlab platform.

  • Detection of Bartonella spp. in fleas by MALDI-TOF MS.
    PLOS Neglected Tropical Diseases, 2018
    Co-Authors: Basma El Hamzaoui, Lionel Almeras, Jean Michel Bérenger, Maureen Laroche, Didier Raoult, Philippe Parola
    Abstract:

    Background Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) has recently emerged in the field of entomology as a promising method for the identification of arthropods and the detection of associated pathogens. Methodology/Principal findings An experimental model of Ctenocephalides felis (cat fleas) infected with Bartonella quintana and Bartonella henselae was developed to evaluate the efficacy of MALDI-TOF MS in distinguishing infected from uninfected fleas, and its ability to distinguish fleas infected with Bartonella quintana from fleas infected with Bartonella henselae. For B. quintana, two groups of fleas received three successive blood meals, infected or not. A total of 140 fleas (100 exposed fleas and 40 control fleas) were engorged on human blood, infected or uninfected with B. quintana. Regarding the second pathogen, two groups of fleas (200 exposed fleas and 40 control fleas) were fed in the same manner with human blood, infected or not with Bartonella henselae. Fleas were dissected longitudinally; one-half was used for assessment of B. quintana and B. henselae infectious status by real-time PCR, and the second half was subjected to MALDI-TOF MS analysis. Comparison of MS spectra from infected fleas and uninfected fleas revealed distinct MS profiles. Blind queries against our MALDI-TOF MS arthropod database, upgraded with reference spectra from B. quintana and B. henselae infected fleas but also non-infected fleas, provided the correct classification for 100% of the different categories of specimens tested on the first model of flea infection with Bartonella quintana. As for Bartonella henselae, 81% of exposed qPCR-positive fleas, 96% of exposed qPCR-negative fleas and 100% of control fleas were correctly identified on the second model of flea infection. MALDI-TOF MS successfully differentiated Bartonella spp.-infected and uninfected fleas and was also able to correctly differentiate fleas infected with Bartonella quintana and fleas infected with Bartonella henselae. MALDI-TOF MS correctly identified flea species as well as their infectious status, consistent with the results of real-time PCR. Conclusions/Significance MALDI-TOF is a promising tool for identification of the infection status of fleas infected with Bartonella spp., which allows new possibilities for fast and accurate diagnosis in medical entomology and vector surveillance.

  • Bartonella bovis and Candidatus Bartonella davousti in cattle from Senegal.
    Comparative Immunology Microbiology and Infectious Diseases, 2016
    Co-Authors: Mustapha Dahmani, Didier Raoult, Masse Sambou, Pierre Scandola, Florence Fenollar, Oleg Mediannikov
    Abstract:

    In Senegal, domestic ruminants play a vital role in the economy and agriculture and as a food source for people. Bartonellosis in animals is a neglected disease in the tropical regions, and little information is available about the occurrence of this disease in African ruminants. Human bartonellosis due to Bartonella quintana has been previously reported in Senegal. In this study, 199 domestic ruminants, including 104 cattle, 43 sheep, and 52 goats were sampled in villages from the Senegalese regions of Sine Saloum and Casamance. We isolated 29 Bartonella strains, all exclusively from cattle. Molecular and genetic characterization of isolated strains identified 27 strains as Bartonella bovis and two strains as potentially new species. The strains described here represent the first Bartonella strains isolated from domestic ruminants in Senegal and the first putative new Bartonella sp. isolated from cattle in Africa.

  • Identification of Novel Zoonotic Activity of Bartonella spp., France
    Emerging Infectious Diseases, 2016
    Co-Authors: Muriel Vayssier-taussat, Pierreedouard Fournier, Sara Moutailler, Frangoise Femenia, Philippe Raymond, Olivier Croce, Bernard La Scola, Didier Raoult
    Abstract:

    Certain Bartonella species are known to cause afebrile bacteremia in humans and other mammals, including B. quintana, the agent of trench fever, and B. henselae, the agent of cat scratch disease. Reports have indicated that animal-associated Bartonella species may cause paucisymptomatic bacteremia and endocarditis in humans. We identified potentially zoonotic strains from 6 Bartonella species in samples from patients who had chronic, subjective symptoms and who reported tick bites. Three strains were B. henselae and 3 were from other animal-associated Bartonella spp. (B. doshiae, B. schoenbuchensis, and B. tribocorum). Genomic analysis of the isolated strains revealed differences from previously sequenced Bartonella strains. Our investigation identifed 3 novel Bartonella spp. strains with human pathogenic potential and showed that Bartonella spp. may be the cause of undifferentiated chronic illness in humans who have been bitten by ticks.

  • pathogenicity and treatment of Bartonella infections
    International Journal of Antimicrobial Agents, 2014
    Co-Authors: Emmanouil Angelakis, Didier Raoult
    Abstract:

    Bartonella spp. are responsible for emerging and re-emerging diseases around the world. The majority of human infections are caused by Bartonella henselae, Bartonella quintana and Bartonella bacilliformis, although other Bartonella spp. have also been associated with clinical manifestations in humans. The severity of Bartonella infection correlates with the patient's immune status. Clinical manifestations can range from benign and self-limited to severe and life-threatening disease. Clinical conditions associated with Bartonella spp. include local lymphadenopathy, bacteraemia, endocarditis, and tissue colonisation resulting in bacillary angiomatosis and peliosis hepatis. Without treatment, Bartonella infection can cause high mortality. To date, no single treatment is effective for all Bartonella-associated diseases. In the absence of systematic reviews, treatment decisions for Bartonella infections are based on case reports that test a limited number of patients. Antibiotics do not significantly affect the cure rate in patients with Bartonella lymphadenopathy. Patients with Bartonella spp. bacteraemia should be treated with gentamicin and doxycycline, but chloramphenicol has been proposed for the treatment of B. bacilliformis bacteraemia. Gentamicin in combination with doxycycline is considered the best treatment regimen for endocarditis, and erythromycin is the first-line antibiotic therapy for the treatment of angioproliferative lesions. Rifampicin or streptomycin can be used to treat verruga peruana. In this review, we present recent data and recommendations related to the treatment of Bartonella infections based on the pathogenicity of Bartonella spp.

  • Bartonella rattaustraliani sp nov Bartonella queenslandensis sp nov and Bartonella coopersplainsensis sp nov identified in australian rats
    International Journal of Systematic and Evolutionary Microbiology, 2009
    Co-Authors: Vijay A K B Gundi, Didier Raoult, Carmel T Taylor, Bernard La Scola
    Abstract:

    A total of 11 Bartonella isolates were recovered from the blood of Melomys, Uromys and Rattus species in Australia and were characterized using phenotypic and genotypic methods. Comparison of 16S rRNA gene, ftsZ, gltA and 16S–23S rRNA internal transcribed spacer region sequences from the isolates indicated that they formed three sequence similarity groups that were distinct from one another and from the currently recognized Bartonella species. Phylogenetic analysis based on alignment of concatenated sequences inferred distinct evolutionary lineages for each of the three groups within the genus Bartonella. On the basis of these data, we propose the isolates be accommodated in three novel Bartonella species, namely Bartonella rattaustraliani sp. nov. (type strain AUST/NH4T =CIP 109051T =CCUG 52161T =CSUR B609T), Bartonella queenslandensis sp. nov. (type strain AUST/NH12T =CIP 109057T =CCUG 52167T =CSUR B617T) and Bartonella coopersplainsensis sp. nov. (type strain AUST/NH20T =CIP 109064T =CCUG 52174T =CSUR B619T).

Christoph Dehio - One of the best experts on this subject based on the ideXlab platform.

  • a translocated effector required for Bartonella dissemination from derma to blood safeguards migratory host cells from damage by co translocated effectors
    PLOS Pathogens, 2014
    Co-Authors: Rusudan Okujava, Muriel Vayssiertaussat, Patrick Guye, Yunyueh Lu, Claudia Mistl, Florine Polus, Cornelia Halin, Antonius G Rolink, Christoph Dehio
    Abstract:

    Numerous bacterial pathogens secrete multiple effectors to modulate host cellular functions. These effectors may interfere with each other to efficiently control the infection process. Bartonellae are Gram-negative, facultative intracellular bacteria using a VirB type IV secretion system to translocate a cocktail of Bartonella effector proteins (Beps) into host cells. Based on in vitro infection models we demonstrate here that BepE protects infected migratory cells from injurious effects triggered by BepC and is required for in vivo dissemination of bacteria from the dermal site of inoculation to blood. Human endothelial cells (HUVECs) infected with a ΔbepE mutant of B. henselae (Bhe) displayed a cell fragmentation phenotype resulting from Bep-dependent disturbance of rear edge detachment during migration. A ΔbepCE mutant did not show cell fragmentation, indicating that BepC is critical for triggering this deleterious phenotype. Complementation of ΔbepE with BepEBhe or its homologues from other Bartonella species abolished cell fragmentation. This cyto-protective activity is confined to the C-terminal Bartonella intracellular delivery (BID) domain of BepEBhe (BID2.EBhe). Ectopic expression of BID2.EBhe impeded the disruption of actin stress fibers by Rho Inhibitor 1, indicating that BepE restores normal cell migration via the RhoA signaling pathway, a major regulator of rear edge retraction. An intradermal (i.d.) model for B. tribocorum (Btr) infection in the rat reservoir host mimicking the natural route of infection by blood sucking arthropods allowed demonstrating a vital role for BepE in bacterial dissemination from derma to blood. While the Btr mutant ΔbepDE was abacteremic following i.d. inoculation, complementation with BepEBtr, BepEBhe or BIDs.EBhe restored bacteremia. Given that we observed a similar protective effect of BepEBhe on infected bone marrow-derived dendritic cells migrating through a monolayer of lymphatic endothelial cells we propose that infected dermal dendritic cells may be involved in disseminating Bartonella towards the blood stream in a BepE-dependent manner.

  • persistence of Bartonella spp stealth pathogens from subclinical infections to vasoproliferative tumor formation
    Fems Microbiology Reviews, 2012
    Co-Authors: Arto T Pulliainen, Christoph Dehio
    Abstract:

    Bartonella spp. are facultative intracellular bacteria that typically cause a long-lasting intraerythrocytic bacteremia in their mammalian reservoir hosts, thereby favoring transmission by blood-sucking arthropods. In most cases, natural reservoir host infections are subclinical and the relapsing intraerythrocytic bacteremia may last weeks, months or even years. In this review, we will follow the infection cycle of Bartonella spp. in a reservoir host, which typically starts with an intradermal inoculation of bacteria that are superficially scratched into the skin from arthropod feces and terminates with the pathogen exit by the blood-sucking arthropod. The current knowledge of bacterial countermeasures against mammalian immune response will be presented for each critical step of the pathogenesis. The prevailing models of the still-enigmatic primary niche, the anatomical location where bacteria reside, persist and are periodically seeded into the bloodstream to cause the typical relapsing Bartonella spp. bacteremia will also be critically discussed. The review will end up with a discussion of the ability of Bartonella spp., namely Bartonella henselae, Bartonella quintana and Bartonella bacilliformis, to induce tumor-like vascular deformations in humans having compromised immune response such as in AIDS patients.

  • intruders below the radar molecular pathogenesis of Bartonella spp
    Clinical Microbiology Reviews, 2012
    Co-Authors: Alexander Harms, Christoph Dehio
    Abstract:

    Summary: Bartonella spp. are facultative intracellular pathogens that employ a unique stealth infection strategy comprising immune evasion and modulation, intimate interaction with nucleated cells, and intraerythrocytic persistence. Infections with Bartonella are ubiquitous among mammals, and many species can infect humans either as their natural host or incidentally as zoonotic pathogens. Upon inoculation into a naive host, the Bartonellae first colonize a primary niche that is widely accepted to involve the manipulation of nucleated host cells, e.g., in the microvasculature. Consistently, in vitro research showed that Bartonella harbors an ample arsenal of virulence factors to modulate the response of such cells, gain entrance, and establish an intracellular niche. Subsequently, the bacteria are seeded into the bloodstream where they invade erythrocytes and give rise to a typically asymptomatic intraerythrocytic bacteremia. While this course of infection is characteristic for natural hosts, zoonotic infections or the infection of immunocompromised patients may alter the path of Bartonella and result in considerable morbidity. In this review we compile current knowledge on the molecular processes underlying both the infection strategy and pathogenesis of Bartonella and discuss their connection to the clinical presentation of human patients, which ranges from minor complaints to life-threatening disease.

  • conjugative dna transfer into human cells by the virb vird4 type iv secretion system of the bacterial pathogen Bartonella henselae
    Proceedings of the National Academy of Sciences of the United States of America, 2011
    Co-Authors: Gunnar Schroder, Ralf Schuelein, Maxime Quebatte, Christoph Dehio
    Abstract:

    Bacterial type IV secretion systems (T4SS) mediate interbacterial conjugative DNA transfer and transkingdom protein transfer into eukaryotic host cells in bacterial pathogenesis. The sole bacterium known to naturally transfer DNA into eukaryotic host cells via a T4SS is the plant pathogen Agrobacterium tumefaciens. Here we demonstrate T4SS-mediated DNA transfer from a human bacterial pathogen into human cells. We show that the zoonotic pathogen Bartonella henselae can transfer a cryptic plasmid occurring in the Bartonellae into the human endothelial cell line EA.hy926 via its T4SS VirB/VirD4. DNA transfer into EA.hy926 cells was demonstrated by using a reporter derivative of this Bartonella-specific mobilizable plasmid generated by insertion of a eukaryotic egfp-expression cassette. Fusion of the C-terminal secretion signal of the endogenous VirB/VirD4 protein substrate BepD with the plasmid-encoded DNA-transport protein Mob resulted in a 100-fold increased DNA transfer rate. Expression of the delivered egfp gene in EA.hy926 cells required cell division, suggesting that nuclear envelope breakdown may facilitate passive entry of the transferred ssDNA into the nucleus as prerequisite for complementary strand synthesis and transcription of the egfp gene. Addition of an eukaryotic neomycin phosphotransferase expression cassette to the reporter plasmid facilitated selection of stable transgenic EA.hy926 cell lines that display chromosomal integration of the transferred plasmid DNA. Our data suggest that T4SS-dependent DNA transfer into host cells may occur naturally during human infection with Bartonella and that these chronically infecting pathogens have potential for the engineering of in vivo gene-delivery vectors with applications in DNA vaccination and therapeutic gene therapy.

  • ecological fitness and strategies of adaptation of Bartonella species to their hosts and vectors
    Veterinary Research, 2009
    Co-Authors: Bruno B Chomel, Jane E Koehler, Henrijean Boulouis, Edward B Breitschwerdt, Rickie W Kasten, Muriel Vayssiertaussat, Richard L J Birtles, Christoph Dehio
    Abstract:

    Bartonella spp. are facultative intracellular bacteria that cause characteristic hostrestricted hemotropic infections in mammals and are typically transmitted by blood-sucking arthropods. In the mammalian reservoir, these bacteria initially infect a yet unrecognized primary niche, which seeds organisms into the blood stream leading to the establishment of a long-lasting intra-erythrocytic bacteremia as the hall-mark of infection. Bacterial type IV secretion systems, which are supra-molecular transporters ancestrally related to bacterial conjugation systems, represent crucial pathogenicity factors that have contributed to a radial expansion of the Bartonella lineage in nature by facilitating adaptation to unique mammalian hosts. On the molecular level, the type IV secretion system VirB/VirD4 is known to translocate a cocktail of different effector proteins into host cells, which subvert multiple cellular functions to the benefit of the infecting pathogen. Furthermore, bacterial adhesins mediate a critical, early step in the pathogenesis of the Bartonellae by binding to extracellular matrix components of host cells, which leads to firm bacterial adhesion to the cell surface as a prerequisite for the efficient translocation of type IV secretion effector proteins. The best-studied adhesins in Bartonellae are the orthologous trimeric autotransporter adhesins, BadA in Bartonella henselae and the Vomp family in Bartonella quintana. Genetic diversity and strain variability also appear to enhance the ability of Bartonellae to invade not only specific reservoir hosts, but also accidental hosts, as shown for B. henselae. Bartonellae have been identified in many different blood-sucking arthropods, in which they are typically found to cause extracellular infections of the mid-gut epithelium. Adaptation to specific vectors and reservoirs seems to be a common strategy of Bartonellae for transmission and host diversity. However, knowledge regarding arthropod specificity/rest

Bruno B Chomel - One of the best experts on this subject based on the ideXlab platform.

  • Pathology of Bartonella endocarditis in six dogs.
    Veterinary Pathology, 2020
    Co-Authors: Patricia A Pesavento, Bruno B Chomel, Rickie W Kasten, K. A. Mcdonald, Frederick C Mohr
    Abstract:

    In a 5-year retrospective study of dogs presenting to the Veterinary Medical Teaching Hospital at the University of California, Davis, there were 31 histologic diagnoses of valvular endocarditis. By poly- merase chain reaction (PCR) amplification of embedded valvular tissue, Bartonella organisms were exclusively associated with 6 out of 31 cases (19%). Confirmed Bartonella cases involved the aortic valve alone (five out of six) or in combination with the mitral valve (one of six). Microscopic features of Bartonella endocarditis were compared with valves from non-Bartonella endocarditis and with valvular change unrelated to infectious agents (endocardiosis). Features of Bartonella endocarditis included a combination of fibrosis, mineralization, endothelial proliferation, and neovascularization with variable inflammation. None of these features is specific; however, the combination is distinct both from endocarditis caused by culturable bacteria and from endocar- diosis. Ultrastructural analyses revealed both extracellular and intraendothelial bacteria. Clinical history, serol- ogy, and PCR are currently necessary to establish an etiologic diagnosis of Bartonella endocarditis.

  • Bartonella bovis and Bartonella chomelii infection in dairy cattle and their ectoparasites in Algeria.
    Comparative Immunology Microbiology and Infectious Diseases, 2020
    Co-Authors: G. Boularias, Bruno B Chomel, Nadia Haddad, Naouelle Azzag, C. Gandoin, C. Bouillin, Henrijean Boulouis
    Abstract:

    Abstract Bartonella are blood-borne and vector-transmitted bacteria, some of which are zoonotic. B. bovis and B. chomelii have been reported in cattle. However, no information has yet been provided on Bartonella infection in cattle in Algeria. Therefore, 313 cattle from 45 dairy farms were surveyed in Kabylia, Algeria, in order to identify Bartonella species infecting cattle using serological and molecular tests. In addition, 277 ticks and 33 Hippoboscidae flies were collected. Bartonella bovis and B. chomelii were identified as the two species infecting cattle. Bartonella DNA was also amplified from 6.8 % (n = 19) of ticks and 78.8 % (n = 26) of flies. Prevalence of B. bovis DNA in dairy cattle was associated both with age and altitude. This study is the first one to report of bovine bartonellosis in Algeria, both in dairy cattle and in potential Bartonella vectors, with the detection of B. bovis DNA in tick samples and B. chomelii in fly samples.

  • Detection of Bartonella species, including Candidatus Bartonella ovis sp. nov, in ruminants from Mexico and lack of evidence of Bartonella DNA in saliva of common vampire bats (Desmodus rotundus) predating on them.
    Veterinary Microbiology, 2018
    Co-Authors: Adam P. Raya, Bruno B Chomel, Matthew J. Stuckey, David A. Jaffe, Peter M. Tsou, Aaron Z. Davis, José Ignacio Olave-leyva, Guillermo Galvez-romero, Rickie W Kasten
    Abstract:

    Bartonella spp. have been identified in many bat species worldwide, including the zoonotic species, Candidatus Bartonella mayotimonensis. The common vampire bat (Desmodus rotundus) preys preferentially on livestock in Latin America and is frequently infected with Bartonella spp. To determine the potential role of D. rotundus in transmitting Bartonella to livestock, common vampire bats and bat-bitten domestic ruminants from Mexico were tested for Bartonella infection by blood culture or conventional PCR. Furthermore, to explore the possibility of bite transmission during blood feeding, saliva swabs from 35 D. rotundus known to be either Bartonella bacteremic (N = 17) or blood culture negative (N = 18) were tested by PCR to detect the presence of Bartonella DNA. Twenty (17.1%) of 117 sheep and 16 (34.8%) of 46 cattle were Bartonella bacteremic by PCR testing. However, none of them were infected with Bartonella strains previously isolated from vampire bats and none of the 35 D. rotundus saliva swabs tested were PCR positive for Bartonella. All but two animals among those which were Bartonella culture and/or PCR positive, were infected with either B. bovis (cattle) or B. melophagi (sheep). Two sheep were infected by a possible new species, Candidatus Bartonella ovis, being phylogenetically closer to B. bovis than B. melophagi. This study does not support the role of D. rotundus as a reservoir of Bartonella species infecting livestock, which could be transmitted via bite and blood feeding and therefore suggest limited risk of zoonotic transmission of Bartonella from common vampire bats to humans.

  • Bartonella, bats and bugs: A review.
    Comparative Immunology Microbiology and Infectious Diseases, 2017
    Co-Authors: Matthew J. Stuckey, Bruno B Chomel, Henrijean Boulouis, Eloi Claret De Fleurieu, Alvaro Aguilar-setién, Chao Chin Chang
    Abstract:

    Abstract Ecological, immunological, and epidemiological factors enable bats to transmit an increasingly recognized spectrum of zoonotic agents, and Bartonellae are among those emerging pathogens identified in bats and their arthropod ectoparasites. Current data reveal a multifaceted disease ecology where diverse host species distributed around the world interact with a number of Bartonella spp. and several potential vectors. This review summarizes the methods and findings of studies conducted since 2005 to illustrate that Bartonella bacteremia varies by bat species, location, and other potential variables, such as diet with a very high prevalence in hematophagous bats. Among bat families, Bartonella prevalence ranged from 7.3% among Nycteridae to 54.4% in Miniopteridae. Further research can build on these current data to better determine risk factors associated with Bartonella infection in bat populations and the role of their ectoparasites in transmission.

  • Candidatus Bartonella merieuxii, a Potential New Zoonotic Bartonella Species in Canids from Iraq
    PLOS Neglected Tropical Diseases, 2012
    Co-Authors: Bruno B Chomel, Rickie W Kasten, Matthew J. Stuckey, Audrey C. Mcmillan-cole, Shingo Sato, Soichi Maruyama, Pedro Paulo Vissotto De Paiva Diniz, Edward B Breitschwerdt
    Abstract:

    Bartonellae are emerging vector-borne pathogens infecting erythrocytes and endothelial cells of various domestic and wild mammals. Blood samples were collected from domestic and wild canids in Iraq under the United States Army zoonotic disease surveillance program. Serology was performed using an indirect immunofluorescent antibody test for B. henselae, B. clarridgeiae, B. vinsonii subsp. berkhoffii and B. bovis. Overall seroprevalence was 47.4% in dogs (n=97), 40.4% in jackals (n=57) and 12.8% in red foxes (n=39). Bartonella species DNA was amplified from whole blood and representative strains were sequenced. DNA of a new Bartonella species similar to but distinct from B. bovis, was amplified from 37.1% of the dogs and 12.3% of the jackals. B. vinsonii subsp. berkhoffii was also amplified from one jackal and no Bartonella DNA was amplified from foxes. Adjusting for age, the odds of dogs being Bartonella PCR positive were 11.94 times higher than for wild canids (95% CI: 4.55–31.35), suggesting their role as reservoir for this new Bartonella species. This study reports on the prevalence of Bartonella species in domestic and wild canids of Iraq and provides the first detection of Bartonella in jackals. We propose Candidatus Bartonella merieuxii for this new Bartonella species. Most of the Bartonella species identified in sick dogs are also pathogenic for humans. Therefore, seroprevalence in Iraqi dog owners and bacteremia in Iraqi people with unexplained fever or culture negative endocarditis requires further investigation as well as in United States military personnel who were stationed in Iraq. Finally, it will also be essential to test any dog brought back from Iraq to the USA for presence of Bartonella bacteremia to prevent any accidental introduction of a new Bartonella species to the New World.

Henrijean Boulouis - One of the best experts on this subject based on the ideXlab platform.

  • Bartonella bovis and Bartonella chomelii infection in dairy cattle and their ectoparasites in Algeria.
    Comparative Immunology Microbiology and Infectious Diseases, 2020
    Co-Authors: G. Boularias, Bruno B Chomel, Nadia Haddad, Naouelle Azzag, C. Gandoin, C. Bouillin, Henrijean Boulouis
    Abstract:

    Abstract Bartonella are blood-borne and vector-transmitted bacteria, some of which are zoonotic. B. bovis and B. chomelii have been reported in cattle. However, no information has yet been provided on Bartonella infection in cattle in Algeria. Therefore, 313 cattle from 45 dairy farms were surveyed in Kabylia, Algeria, in order to identify Bartonella species infecting cattle using serological and molecular tests. In addition, 277 ticks and 33 Hippoboscidae flies were collected. Bartonella bovis and B. chomelii were identified as the two species infecting cattle. Bartonella DNA was also amplified from 6.8 % (n = 19) of ticks and 78.8 % (n = 26) of flies. Prevalence of B. bovis DNA in dairy cattle was associated both with age and altitude. This study is the first one to report of bovine bartonellosis in Algeria, both in dairy cattle and in potential Bartonella vectors, with the detection of B. bovis DNA in tick samples and B. chomelii in fly samples.

  • Bartonella, bats and bugs: A review.
    Comparative Immunology Microbiology and Infectious Diseases, 2017
    Co-Authors: Matthew J. Stuckey, Bruno B Chomel, Henrijean Boulouis, Eloi Claret De Fleurieu, Alvaro Aguilar-setién, Chao Chin Chang
    Abstract:

    Abstract Ecological, immunological, and epidemiological factors enable bats to transmit an increasingly recognized spectrum of zoonotic agents, and Bartonellae are among those emerging pathogens identified in bats and their arthropod ectoparasites. Current data reveal a multifaceted disease ecology where diverse host species distributed around the world interact with a number of Bartonella spp. and several potential vectors. This review summarizes the methods and findings of studies conducted since 2005 to illustrate that Bartonella bacteremia varies by bat species, location, and other potential variables, such as diet with a very high prevalence in hematophagous bats. Among bat families, Bartonella prevalence ranged from 7.3% among Nycteridae to 54.4% in Miniopteridae. Further research can build on these current data to better determine risk factors associated with Bartonella infection in bat populations and the role of their ectoparasites in transmission.

  • Experimental Infection of Horses with Bartonella henselae and Bartonella bovis
    Journal of Veterinary Internal Medicine, 2012
    Co-Authors: J. Palmero, Henrijean Boulouis, Edward B Breitschwerdt, Rickie W Kasten, Natalie A Cherry, Nicola Pusterla, Samantha Mapes, Bruno B Chomel
    Abstract:

    Background Experimental infection of horses with Bartonella species is not documented. Objectives Determine clinical signs, hematologic changes, duration of bacteremia, and pattern of seroconversion in Bartonella henselae or Bartonella bovis-inoculated horses. Animals Twelve (2 groups of 6) randomly selected healthy adult horses seronegative and culture negative for Bartonella spp. Methods Experimental/observational study: Group I: B. henselae or saline control was inoculated intradermally into 4 naive and 2 sentinel horses, respectively. Group II: same design was followed by means of B. bovis. Daily physical examinations, once weekly CBC, immunofluorescent antibody assay serology, real-time polymerase chain reaction (PCR), and twice weekly blood cultures were performed for 6 weeks and at postinoculation day 80 and 139. Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment blood culture was performed for horses that seroconverted to B. henselae antigens. Results Transient clinical signs consistent with bartonellosis occurred in some Bartonella-inoculated horses, but hematological alterations did not occur. Three B. henselae-inoculated horses seroconverted, whereas 1 B. bovis-inoculated horse was weakly seropositive. In Group I, B. henselae was amplified and sequenced from BAPGM blood culture as well as a subculture isolate from 1 horse, blood from a 2nd horse, and BAPGM blood culture from a 3rd horse although a subculture isolate was not obtained. All sentinels remained PCR, culture, and serology negative. Conclusions Detection of Bartonella sp. in blood after experimental inoculation supports bacteremia and seroconversion. Culture with BAPGM may be required to detect Bartonella sp. Although mild clinical signs followed acute infection, no long-term effects were noted for 2 years postinoculation.

  • Bartonella japonica sp. nov. and Bartonella silvatica sp. nov., isolated from Apodemus mice
    International Journal of Systematic and Evolutionary Microbiology, 2010
    Co-Authors: Kai Inoue, Bruno B Chomel, Henrijean Boulouis, Michael Y. Kosoy, Hidenori Kabeya, Hatsumi Shiratori, Kenji Ueda, Soichi Maruyama
    Abstract:

    Two bacterial strains, Fuji 18-1T and Fuji 23-1T, were isolated from the blood of the small Japanese field mouse (Apodemus argenteus) and the large Japanese field mouse (Apodemus speciosus), respectively, specimens of which were captured in the forest of Mount Fuji, Japan. Phenotypic characterization (growth conditions, incubation periods, biochemical properties and cell morphologies), DNA G+C contents (40.1 mol% for strain Fuji 18-1T and 40.4 mol% for strain Fuji 23-1T) and sequence analyses of the 16S rRNA genes indicated that both strains were members of the genus Bartonella. Using rpoB and gltA sequencing analysis, the highest sequence similarities between strains Fuji 18-1T, Fuji 23-1T and other recognized species of the genus Bartonella showed values considerably lower than 91.4 % and 89.9 % in the rpoB gene and 89.1 % and 90.4 % in the gltA gene, respectively. It is known that similarities of 95.4 % for the rpoB gene and 96.0 % for the gltA gene can be applied as cut-off values for the designation of novel species of the genus Bartonella. In a phylogenetic tree based on the merged set of concatenated sequences of seven loci [16S rRNA, ftsZ, gltA, groEL, ribC and rpoB genes and the intergenic spacer region (ITS)], strains Fuji 18-1T and Fuji 23-1T formed a distinct clade from other recognized species of the genus Bartonella. These data support the classification of strains Fuji 18-1T and Fuji 23-1T as novel species of the genus Bartonella. The names Bartonella japonica sp. nov. and Bartonella silvatica sp. nov. are proposed for these novel species. The type strains of Bartonella japonica sp. nov. and Bartonella silvatica sp. nov. are Fuji 18-1T (=JCM 15567T=CIP 109861T) and Fuji 23-1T (=JCM 15566T=CIP 109862T), respectively.

  • The Trw Type IV Secretion System of Bartonella Mediates Host-Specific Adhesion to Erythrocytes
    PLoS Pathogens, 2010
    Co-Authors: Muriel Taussat, Henrijean Boulouis, Danielle Le Rhun, H.k. Deng, Francis Biville, Sandra Cescau, Antoine Danchin, Geneviève Marignac, Evelyne Lenaour, Arnaud Lionel Mavris
    Abstract:

    Bacterial pathogens typically infect only a limited range of hosts; however, the genetic mechanisms governing host-specificity are poorly understood. The alpha-proteobacterial genus Bartonella comprises 21 species that cause host-specific intraerythrocytic bacteremia as hallmark of infection in their respective mammalian reservoirs, including the human-specific pathogens Bartonella quintana and Bartonella bacilliformis that cause trench fever and Oroya fever, respectively. Here, we have identified bacterial factors that mediate host-specific erythrocyte colonization in the mammalian reservoirs. Using mouse-specific Bartonella birtlesii, human-specific Bartonella quintana, cat-specific Bartonella henselae and rat-specific Bartonella tribocorum, we established in vitro adhesion and invasion assays with isolated erythrocytes that fully reproduce the host-specificity of erythrocyte infection as observed in vivo. By signature-tagged mutagenesis of B. birtlesii and mutant selection in a mouse infection model we identified mutants impaired in establishing intraerythrocytic bacteremia. Among 45 abacteremic mutants, five failed to adhere to and invade mouse erythrocytes in vitro. The corresponding genes encode components of the type IV secretion system (T4SS) Trw, demonstrating that this virulence factor laterally acquired by the Bartonella lineage is directly involved in adherence to erythrocytes. Strikingly, ectopic expression of Trw of rat-specific B. tribocorum in cat-specific B. henselae or human-specific B. quintana expanded their host range for erythrocyte infection to rat, demonstrating that Trw mediates host-specific erythrocyte infection. A molecular evolutionary analysis of the trw locus further indicated that the variable, surface-located TrwL and TrwJ might represent the T4SS components that determine host-specificity of erythrocyte parasitism. In conclusion, we show that the laterally acquired Trw T4SS diversified in the Bartonella lineage to facilitate host-restricted adhesion to erythrocytes in a wide range of mammals.