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Role of NK cells in host defense against pulmonary type A Francisella tularensis infection. Microbes Infect 2012; 15:201-11. [PMID: 23211929 DOI: 10.1016/j.micinf.2012.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/25/2012] [Accepted: 11/15/2012] [Indexed: 01/16/2023]
Abstract
Pneumonic tularemia is a potentially fatal disease caused by the Category A bioterrorism agent Francisella tularensis. Understanding the pulmonary immune response to this bacterium is necessary for developing effective vaccines and therapeutics. In this study, characterization of immune cell populations in the lungs of mice infected with the type A strain Schu S4 revealed a significant loss in natural killer (NK) cells over time. Since this decline in NK cells correlated with morbidity and mortality, we hypothesized these cells contribute to host defense against Schu S4 infection. Depletion of NK cells prior to Schu S4 challenge significantly reduced IFN-γ and granzyme B in the lung but had no effect on bacterial burden or disease progression. Conversely, increasing NK cell numbers with the anti-apoptotic cytokine IL-15 and soluble receptor IL-15Rα had no significant impact on Schu S4 growth in vivo. A modest decrease in median time to death, however, was observed in live vaccine strain (LVS)-vaccinated mice depleted of NK1.1+ cells and challenged with Schu S4. Therefore, NK cells do not appear to contribute to host defense against acute respiratory infection with type A F. tularensis in vivo, but they play a minor role in protection elicited by LVS vaccination.
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Dergousoff SJ, Chilton NB. Association of different genetic types of Francisella-like organisms with the rocky mountain wood tick (Dermacentor andersoni) and the American dog tick (Dermacentor variabilis) in localities near their northern distributional limits. Appl Environ Microbiol 2012; 78:965-71. [PMID: 22179251 PMCID: PMC3272999 DOI: 10.1128/aem.05762-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 12/03/2011] [Indexed: 11/20/2022] Open
Abstract
Dermacentor andersoni and Dermacentor variabilis from allopatric and sympatric populations near their northern distributional limits were examined for the presence of Francisella species using molecular techniques that targeted 373 bp of the 16S rRNA gene. Although there was no evidence for the presence of Francisella tularensis in any tick, Francisella-like endosymbionts (FLEs) were common in D. andersoni and D. variabilis adults and immatures. A significantly greater proportion of female ticks contained FLEs compared to male ticks. In addition, significantly more D. variabilis adult individuals contained multiple FLE sequence types than did D. andersoni adults. Ten different types of FLEs were identified based on the sequence data, which has implications for diagnostic tests and epidemiological studies of F. tularensis in tick populations in Canada. The three most prevalent types of FLEs have been detected previously in D. andersoni or D. variabilis from other parts of their distributional ranges, whereas the other seven FLE types have not been reported previously. A comparison of the FLEs from both allopatric and sympatric populations of these two tick species provided insight into the relative host-specificity and the modes of transmission of these tick-borne bacteria. In general, each FLE type was specific for one tick species, suggesting vertical transmission of each bacterium. However, there were a few instances of potential cross-transfer of two FLE types to the other tick species at locations where D. andersoni and D. variabilis occurred in sympatry, suggesting that there may be occasional horizontal transmission of some FLEs.
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Affiliation(s)
- Shaun J Dergousoff
- Department of Biology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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3
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Q Fever Presenting As Recurrent, Culture-negative Endocarditis with Aortic Prosthetic Valve Failure: A Case Report and Review of the Literature. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2011; 17:341-4. [PMID: 18382649 DOI: 10.1155/2006/152624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 06/27/2006] [Indexed: 11/17/2022]
Abstract
The present report describes a case of recurrent, culture-negative endocarditis presenting with aortic prosthetic valve dysfunction in a 62-year-old man who required four valve replacement surgeries. On each occasion, he presented with valve failure. Fever was only documented during his first presentation. Furthermore, no vegetations were detectable on his aortic valve at transesophageal echocardiography. On the occasion of his most recent presentation, a detailed history of animal exposure - including hunting and skinning deer, moose and other large animals with his bare hands - was the only clue to his diagnosis. Serum antibodies against Coxiella burnetii were strongly positive, and C burnetii DNA was detected by polymerase chain reaction from his resected aortic valve tissue. Q fever is a worldwide zoonotic infection with diverse reservoirs. This diagnosis should be considered when evaluating unexplained prosthetic valve dysfunction, particularly in the setting of animal exposure.
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Human granulocytic anaplasmosis: First reported case in Canada. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2011; 20:e100-2. [PMID: 20808448 DOI: 10.1155/2009/124173] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Human granulocytic anaplasmosis (HGA) is a tick-borne rickettsial infection of peripheral blood neutrophils caused by Anaplasma phagocytophilum. While this infection is increasingly recognized as endemic throughout much of the United States, no Canadian cases have been previously described, despite the agent being identified in Canadian ticks. Herein we present a case of HGA acquired in an urban Alberta centre. Canadian physicians must be aware of the possibility of tick-borne rickettsial diseases as etiology of fever in individuals presenting with leukopenia/lymphopenia, thrombocytopenia and elevated transaminases during periods of tick activity. Prompt recognition and treatment are important in minimizing resultant morbidity and mortality.
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Reese SM, Petersen JM, Sheldon SW, Dolan MC, Dietrich G, Piesman J, Eisen RJ. Transmission efficiency of Francisella tularensis by adult american dog ticks (Acari: Ixodidae). JOURNAL OF MEDICAL ENTOMOLOGY 2011; 48:884-890. [PMID: 21845949 DOI: 10.1603/me11005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The American dog tick, Dermacentor variabilis (Say) (Acari: Ixodidae), has been implicated as a potential bridging vector to humans of Francisella tularensis, the etiological agent of tularemia. Since the initial studies evaluating vector competency of D. variabilis were conducted, F. tularensis has been subdivided into subspecies and clades that differ in their geographical distribution in the United States and in the severity of infections caused in humans. Here, we demonstrate that D. variabilis nymphs efficiently acquire, transtadially maintain, and transmit each of the strains tested (clades A1b and A2, and type B). Transmission efficiency by adult females was similarly high among infection groups and ranged from 58% for type B to 89% for A2 infections. In addition, we demonstrated that transmission can occur shortly after tick attachment. These findings support the concept that D. variabilis adults may play a significant role in epizootic transmission of F. tularensis, and as a bridging vector to humans.
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Affiliation(s)
- Sara M Reese
- Bacterial Diseases Branch, Division of Vector Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3150 Rampart Road, Fort Collins, CO, USA
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6
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Dana AN. Diagnosis and treatment of tick infestation and tick-borne diseases with cutaneous manifestations. Dermatol Ther 2009; 22:293-326. [PMID: 19580576 DOI: 10.1111/j.1529-8019.2009.01244.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hard and soft ticks may be associated directly or indirectly with a number of dermatoses, both infectious and inflammatory in origin. Morbidity may occur as a result of tick bites, tick toxicosis, and even infestation. These arthropod vectors may transmit life-threatening protozoan, bacterial, rickettsial, and viral diseases with systemic and cutaneous findings. Additionally, ticks may transmit more than one pathogen with subsequent human coinfection. This article reviews the presentation of tick-borne illnesses and the medical management of these diseases. Among others, diseases such as ehrlichiosis, anaplasmosis, babesiosis, tularemia, borrelioses, tick-borne encephalitides, rickettsial spotted fevers, and tick typhus are discussed in this article. The recognition of skin manifestations associated with these diseases is paramount to early diagnosis and treatment initiation.
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Affiliation(s)
- Ali N Dana
- Department of Dermatology, Johns Hopkins University, Baltimore, Maryland, USA.
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Georgiev VS. Tick-Borne Bacterial, Rickettsial, Spirochetal, and Protozoal Diseases. NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES, NIH 2009. [PMCID: PMC7122040 DOI: 10.1007/978-1-60327-297-1_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Approximately 900 tick species exist worldwide, parasitizing a broad array of mammals, including humans, and thereby playing a significant role in the transmission of infectious diseases (1). In the United States, tick-borne diseases are generally seasonal and geographically distributed. They occur mostly during the spring and summer but can occur throughout the year.
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Acquisition of the vacuolar ATPase proton pump and phagosome acidification are essential for escape of Francisella tularensis into the macrophage cytosol. Infect Immun 2008; 76:2671-7. [PMID: 18390995 DOI: 10.1128/iai.00185-08] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The Francisella tularensis-containing phagosome (FCP) matures to a late-endosome-like phagosome prior to bacterial escape into the cytosols of macrophages, where bacterial proliferation occurs. Our data show that within the first 15 min after infection of primary human monocyte-derived macrophages (hMDMs), approximately 90% of the FCPs acquire the proton vacuolar ATPase (vATPase) pump and the lysomotropic dye LysoTracker, which concentrates in acidic compartments, similar to phagosomes harboring the Listeria monocytogenes control. The acquired proton vATPase pump and lysomotropic dye are gradually lost by 30 to 60 min postinfection, which coincides with bacterial escape into the cytosols of hMDMs. Colocalization of phagosomes harboring the iglD mutant with the vATPase pump and the LysoTracker dye was also transient, and the loss of colocalization was faster than that observed for the wild-type strain, which is consistent with the faster escape of the iglD mutant into the macrophage cytosol. In contrast, colocalization of both makers with phagosomes harboring the iglC mutant was persistent, which is consistent with fusion to the lysosomes and failure of the iglC mutant to escape into the macrophage cytosol. We have utilized a fluorescence microscopy-based phagosome integrity assay for differential labeling of vacuolar versus cytosolic bacteria, using antibacterial antibodies loaded into the cytosols of live hMDMs. We show that specific inhibition of the proton vATPase pump by bafilomycin A1 (BFA) blocks rapid bacterial escape into the cytosols of hMDMs, but 30% to 50% of the bacteria escape into the cytosol by 6 to 12 h after BFA treatment. The effect of BFA on the blocking of bacterial escape into the cytosol is completely reversible, as the bacteria escape after removal of BFA. We also show that the limited fusion of the FCP to lysosomes is not due to failure to recruit the late-endosomal fusion regulator Rab7. Therefore, within few minutes of its biogenesis, the FCP transiently acquires the proton vATPase pump to acidify the phagosome, and this transient acidification is essential for subsequent bacterial escape into the macrophage cytosol.
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Santic M, Molmeret M, Barker JR, Klose KE, Dekanic A, Doric M, Abu Kwaik Y. A Francisella tularensis pathogenicity island protein essential for bacterial proliferation within the host cell cytosol. Cell Microbiol 2007; 9:2391-403. [PMID: 17517064 DOI: 10.1111/j.1462-5822.2007.00968.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Francisella tularensis is an intracellular bacterial pathogen, and is a category A bioterrorism agent. Within quiescent human macrophages, the F. tularensis pathogenicity island (FPI) is essential for bacterial growth within quiescent macrophages. The F. tularensis-containing phagosome matures to a late endosome-like stage that does not fuse to lysosomes for 1-8 h, followed by gradual bacterial escape into the macrophage cytosol. Here we show that the FPI protein IglD is essential for intracellular replication in primary human monocyte-derived macrophages (hMDMs). While the parental strain replicates robustly in pulmonary, hepatic and splenic tissues of BALB/c mice associated with severe immunopathologies, the isogenic iglD mutant is severely defective. Within hMDMs, the iglD mutant-containing phagosomes mature to either a late endosome-like phagosome, similar to the parental strain, or to a phagolysosome, similar to phagosomes harbouring the iglC mutant control. Despite heterogeneity and alterations in phagosome biogenesis, the iglD mutant bacteria escape into the cytosol faster than the parental strain within hMDMs and pulmonary cells of BALB/c mice. Co-infections of hMDMs with the wild-type strain and the iglD mutant, or super-infection of iglD mutant-infected hMDMs with the wild-type strain show that the mutant strain replicates robustly within the cytosol of hMDMs coinhabited by the wild strain. However, when the wild-type strain-infected hMDMs are super-infected by the iglD mutant, the mutant fails to replicate in the cytosol of communal macrophages. This is the first demonstration of a F. tularensis novel protein essential for proliferation in the macrophage cytosol. Our data indicate that F. tularensis transduces signals to the macrophage cytosol to remodel it into a proliferative niche, and IglD is essential for transduction of these signals.
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Affiliation(s)
- Marina Santic
- Department of Microbiology and Immunology, University of Louisville, College of Medicine, Louisville, KY 40202, USA
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Eisen L. A call for renewed research on tick-borne Francisella tularensis in the Arkansas-Missouri primary national focus of tularemia in humans. JOURNAL OF MEDICAL ENTOMOLOGY 2007; 44:389-97. [PMID: 17547223 DOI: 10.1603/0022-2585(2007)44[389:acfrro]2.0.co;2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Arkansas-Missouri has emerged as the primary U.S. focus of tularemia, which is caused by the National Institute of Allergy and Infectious Diseases Category A Priority Pathogen Francisella tularensis, over the past 30 yr. There are several pieces of indirect evidence suggesting that a key role of ticks in the transmission of F. tularensis to humans in Arkansas-Missouri is the primary reason why tularemia has remained a prominent disease of humans in this two-state area while fading away from other central or eastern states after a general decline in rabbit-associated tularemia cases. The primary tick vector(s) in Arkansas-Missouri can, based on a comparison of seasonal patterns of human tularemia cases and peak host-seeking activity of commonly human-biting tick species and life stages, be narrowed down to Amblyomma americanum (L.) nymphs, A. americanum adults, or Dermacentor variabilis (Say) adults. Unfortunately, currently available data cannot be used to further elucidate the relative roles of these ticks as vectors of F. tularensis to humans in Arkansas-Missouri. To address the fact that we do not know which tick species is the primary vector of F. tularensis to humans in the most prominent U.S. focus of tularemia, we need to determine (1) relative contributions of different tick species and life stages as human biters in Arkansas-Missouri; (2) natural rates of infection with F. tularensis tularensis (type A) and F. tularensis holarctica (type B) of the most prominent human-biting ticks in areas of Arkansas-Missouri hyperendemic for tularemia; (3) experimental vector efficiency of these ticks for both F. tularensis tularensis and F. tularensis holarctica; and (4) presence of infection with F. tularensis tularensis or F tularensis holarctica in ticks collected from humans in Arkansas-Missouri.
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Affiliation(s)
- L Eisen
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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11
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Pappas G, Panagopoulou P, Christou L, Akritidis N. Category B Potential Bioterrorism Agents: Bacteria, Viruses, Toxins, and Foodborne and Waterborne Pathogens. Infect Dis Clin North Am 2006; 20:395-421, x. [PMID: 16762744 DOI: 10.1016/j.idc.2006.02.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Georgios Pappas
- Institute for Continuing Medical Education of Ioannina, Velissariou 15-19, 45221 Ioannina, Greece.
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12
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Fry DE. Disaster Planning for Unconventional Acts of Civilian Terrorism. Curr Probl Surg 2006; 43:253-315. [PMID: 16581341 DOI: 10.1067/j.cpsurg.2006.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Donald E Fry
- University of New Mexico School of Medicine, Albuquerque, USA
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13
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Santic M, Molmeret M, Klose KE, Abu Kwaik Y. Francisella tularensis travels a novel, twisted road within macrophages. Trends Microbiol 2005; 14:37-44. [PMID: 16356719 DOI: 10.1016/j.tim.2005.11.008] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Revised: 10/06/2005] [Accepted: 11/24/2005] [Indexed: 01/02/2023]
Abstract
Francisella tularensis is a highly infectious intracellular bacterium that causes fulminating disease and is a potential bioweapon. Although entry of the bacteria into macrophages is mediated by novel asymmetric, spacious pseudopod loops, the nascent phagosome becomes tight fitting within seconds of formation. Biogenesis of the Francisella-containing phagosome (FCP) is arrested for 2-4h at a unique stage within the endosomal-lysosomal degradation pathway, followed by gradual bacterial escape into the cytosol, where the microbe proliferates. By contrast, other intracellular pathogens either proliferate within an idiosyncratic phagosome or escape within minutes into the cytoplasm to avoid degradation. Thus, trafficking of the FCP defies the dogma of classification of intracellular pathogens into vacuolar or cytosolic. The Francisella pathogenicity island and its transcriptional regulator MglA are essential for arresting biogenesis of the FCP. Despite sophisticated microbial strategies to arrest phagosome biogenesis within quiescent macrophages, trafficking of F. tularensis and other intracellular pathogens within interferon-gamma-activated macrophages is similar, in that the bacterial phagosomes fuse to lysosomes. The potential use of F. tularensis as a bioweapon has generated interest in the study of its molecular pathogenesis to identify targets for therapy, vaccination and rapid diagnosis.
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Affiliation(s)
- Marina Santic
- Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
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Karadenizli A, Gurcan S, Kolayli F, Vahaboglu H. Outbreak of tularaemia in Golcuk, Turkey in 2005: report of 5 cases and an overview of the literature from Turkey. ACTA ACUST UNITED AC 2005; 37:712-6. [PMID: 16191887 DOI: 10.1080/00365540510012125] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Tularaemia was diagnosed by TaqMan RT-PCR and microagglutination tests in 5 patients, all from a new settlement constructed after the earthquake of 1999. During the follow-up, 129 more cases were found in this settlement (data from the local Health Care Authority). In this study, clinical features of 5 cases are presented briefly, and the Turkish literature on past outbreaks of tularaemia is reviewed.
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Affiliation(s)
- Aynur Karadenizli
- From the Mikrobiyoloji ve Klinik Mikrobiyoloji AD, Kocaeli Universitesi, Kocaeli.
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Daya M, Nakamura Y. Pulmonary Disease from Biological Agents: Anthrax, Plague, Q Fever, and Tularemia. Crit Care Clin 2005; 21:747-63, vii. [PMID: 16168313 DOI: 10.1016/j.ccc.2005.06.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Anthrax, plague, Q fever, and tularemia are all potential inhalational bioterrorism agents. The pulmonary manifestations of these agents can be readily confused with each other as well as other more common diseases such as influenza and atypical pneumonia. This article reviews the threat potential, microbiology, pathogenesis, clinical features, diagnosis, and treatment of each of these agents and highlights the similarities and differences between their pulmonary presentations.
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Affiliation(s)
- Mohamud Daya
- Department of Emergency Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd Portland, OR 97239-3098, USA.
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16
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Santic M, Molmeret M, Abu Kwaik Y. Modulation of biogenesis of the Francisella tularensis subsp. novicida-containing phagosome in quiescent human macrophages and its maturation into a phagolysosome upon activation by IFN-gamma. Cell Microbiol 2005; 7:957-67. [PMID: 15953028 DOI: 10.1111/j.1462-5822.2005.00529.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Francisella tularensis is a highly virulent facultative intracellular pathogen that has been categorized as a class A bioterrorism agent, and is classified into four subsp, tularensis, holarctica, mediasiatica and novicida. Although the ability of F. tularensis subsp. novicida to cause tularemia in mice is similar to the virulent subsp. tularensis and holarctica, it is attenuated in humans. It is not known whether attenuation of F. tularensis subsp. novicida in humans is resulting from a different route of trafficking within human macrophages, compared with the tularensis or holarctica subsp. Here we show that in quiescent human monocytes-derived macrophages (hMDMs), the F. tularensis subsp. novicida containing phagosome (FCP) matures into a late endosome-like stage that acquires the late endosomal marker LAMP-2 but does not fuse to lysosomes. This modulation of phagosome biogenesis by F. tularensis is followed by disruption of the phagosome at 4-12 h and subsequent bacterial escape into cytoplasm where the organism replicates. In IFN-gamma-activated hMDMs, intracellular replication of F. tularensis is completely inhibited, and is associated with failure of the organism to escape from the phagosome into the cytoplasm for up to 24 h after infection. In IFN-gamma-activated hMDMs, the FCPs acquire the lysosomal enzymes Cathepsin D, which is excluded in quiescent hMDMs. When the lysosomes of IFN-gamma-activated hMDMs are preload with Texas Red Ovalbumin or BSA-gold, the FCPs acquire both lysosomal tracers. In contrast, both lysosomal tracers are excluded from the FCPs within quiescent hMDMs. We conclude that although F. tularensis subsp. novicida is attenuated in humans, it modulates biogenesis of its phagosome into a late endosome-like compartment followed by bacterial escape into the cytoplasm within quiescent hMDMs, similar to the virulent subsp. tularensis. In IFN-gamma-activated hMDMs, the organism fails to escape into the cytoplasm and its phagosome fuses to lysosomes, similar to inert particles.
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Affiliation(s)
- Marina Santic
- Department of Microbiology and Immunology, Room 316, University of Louisville College of Medicine, 319 Abraham Flexner Way 55A, Louisville, KY 40202, USA
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Abstract
The incidence of skin disease secondary to infestation with the human bedbug, Cimex lectularius, has increased dramatically in the United States and in the United Kingdom. We describe a child with a recurrent pruritic eruption of urticarial, erythematous papules on the face, neck, and extremities. The etiology of her cutaneous lesions was discovered to be a bedbug infestation in the home. The epidemiology, entomology, presentation, and treatment of bedbugs and their bites are discussed.
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Affiliation(s)
- Maryanna C Ter Poorten
- Department of Dermatology, Medical University of South Carolina, Charleston, South Carolina, USA
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18
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Amsden JR, Warmack S, Gubbins PO. Tick-Borne Bacterial, Rickettsial, Spirochetal, and Protozoal Infectious Diseases in the United States: A Comprehensive Review. Pharmacotherapy 2005; 25:191-210. [PMID: 15767235 DOI: 10.1592/phco.25.2.191.56948] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Approximately 900 tick species exist worldwide, and they parasitize a variety of mammals, including humans; thus, ticks play a significant role in the transmission of infectious diseases. In the United States, tick-borne diseases are seasonally and geographically distributed; they typically occur during spring and summer but can occur throughout the year. Tick-borne diseases are endemic to a variety of geographic regions of the United States, depending on the species of tick commonly found in a specific locale. Specific tick-borne diseases are difficult to diagnose. Most patients have vague constitutional symptoms and nonspecific laboratory findings. Initially, serologic methods are of little benefit because they lack sensitivity early in the disease course. Therefore, a thorough history and physical examination are necessary for establishing a diagnosis. Antimicrobial regimens for tick-borne infections are poorly studied but well established. Tetracyclines and rifampin form the cornerstones of therapy for most tick-borne infections, but these agents may not be suitable for all patient populations. Therefore, no single agent can be chosen empirically to treat all tick-borne diseases. Because pharmacists are the most accessible health care providers, they are often asked how to treat tick-borne diseases. Thus, practitioners should be familiar with the ticks that inhabit their locale.
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Affiliation(s)
- Jarrett R Amsden
- Department of Pharmacy Practice, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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Abstract
Tularemia is a bacterial infection usually transmitted via arthropod vectors or direct contact with infected animals. Naturally occurring cases are relatively rare, and can result in six different clinical syndromes. Tularemia is also a potential agent of bioterrorism or biowarfare, and is categorized as a high-level threat. Effective antibiotic treatment is available, including potential use of oral antibiotics in a mass casualty situation. An awareness of potential clinical presentations of tularemia will facilitate timely intervention,appropriate diagnostic testing, and decreased morbidity in the event of a biologic attack with Francisella tularensis.
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Affiliation(s)
- Steven D Cronquist
- Department of Dermatology, Naval Hospital Great Lakes, 3001A Sixth Street, Great Lakes, IL 60088, USA.
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20
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Abstract
Infections due to Coxiella burnetii, the causative organism of Q fever, are extremely rare in North America. Endocarditis due to the organism has an unusual presentation and poses echocardiographic and laboratory challenges in establishing a diagnosis. We describe the presentation and clinical course of a 40-year-old American man with Q fever endocarditis and briefly discuss the salient issues regarding this entity.
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Affiliation(s)
- Apoor S Gami
- Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minn 55905, USA
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21
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Madariaga MG, Rezai K, Trenholme GM, Weinstein RA. Q fever: a biological weapon in your backyard. THE LANCET. INFECTIOUS DISEASES 2003; 3:709-21. [PMID: 14592601 DOI: 10.1016/s1473-3099(03)00804-1] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Coxiella burnetii, which causes Q fever, is a highly infectious agent that is widespread among livestock around the world. Although the culture process for coxiella is laborious, large amounts of infectious material can be produced. If used as an aerosolised biological weapon, coxiella may not cause high mortality, but could provoke acute disabling disease. In its late course, Q fever can be complicated by fatal (eg, endocarditis) or debilitating (eg, chronic fatigue syndrome) disorders. The diagnosis of Q fever might be delayed because of non-specific and protean presentations. Effective antibiotic treatment is available for the acute form of disease but not for the chronic complications. Vaccination and chemoprophylaxis in selected individuals may be used in the event of bioterrorism.
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Affiliation(s)
- Miguel G Madariaga
- Division of Infectious Disease, Cook County Hospital, Chicago and the Section of Infectious Diseases, Rush-Presbyterian-St Luke's Medical Center, Chicago, IL 60612, USA.
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Han SZ, Alfano MC, Psoter WJ, Rekow ED. Bioterrorism and catastrophe response: a quick-reference guide to resources. J Am Dent Assoc 2003; 134:745-52. [PMID: 12839411 DOI: 10.14219/jada.archive.2003.0261] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Dentists' responses to catastrophe have been redefined by bioterrorism. Informed response requires accurate information about agents and diseases that have the potential to be used as weapons. METHODS The authors reviewed information about the most probable bioterrorist weapons (those from the Center for Disease Control and Prevention's Category A) from the World Wide Web and print journals and distilled it into a resource list that is current, relevant to dentistry and noncommercial. The Web sites cited include those sponsored by federal agencies, academic institutions and professional organizations. The articles cited include those published in English within the last six years in refereed journals that are available in most higher education institutions. RESULTS The authors present the information in a table that provides a quick-reference guide to resources describing agents and diseases with the greatest potential for use as weapons: anthrax, botulism, plague, smallpox, tularemia and viral hemorrhagic fevers. This article presents Web site and journal citations for background and patient-oriented information (fact sheets), signs and symptoms, and prophylactic measures and treatment for each of the agents and diseases. The table facilitates quick access to this information, especially in an emergency. This article also points out guidelines for response should a suspected attack occur. CONCLUSIONS Armed with information about biological weapons, dentists can provide faster diagnosis, inform their patients about risks, prophylaxis or treatment and rethink their own role in terrorism response. CLINICAL IMPLICATIONS Fast, accurate diagnosis limits the spread of exceptionally contagious diseases. Providing accurate information to patients minimizes misinformation and the associated public fear and panic that, unchecked, could overwhelm health care systems.
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Affiliation(s)
- Susan Z Han
- Harvard School of Dental Medicine, Boston, USA
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