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Hemeg HA, Albulushi HO, Ozbak HA, Ali HM, Alahmadi EK, Almutawif YA, Alhuofie ST, Alaeq RA, Alhazmi AA, Najim MA, Hanafy AM. Evaluating the Sensitivity of Different Molecular Techniques for Detecting Mycobacterium tuberculosis Complex in Patients with Pulmonary Infection. Pol J Microbiol 2023; 72:421-431. [PMID: 37934050 PMCID: PMC10725165 DOI: 10.33073/pjm-2023-040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 10/04/2023] [Indexed: 11/08/2023] Open
Abstract
This study aimed to evaluate the accuracy of detecting drug-resistant Mycobacterium tuberculosis complex (MTBC)-specific DNA in sputum specimens from 48 patients diagnosed with pulmonary tuberculosis. The presence of MTBC DNA in the specimens was validated using the GeneXpert MTB/RIF system and compared with a specific PCR assay targeting the IS6110 and the mtp40 gene sequence fragments. Additionally, the results obtained by multiplex PCR assays to detect the most frequently encountered rifampin, isoniazid, and ethambutol resistance-conferring mutations were matched with those obtained by GeneXpert and phenotypic culture-based drug susceptibility tests. Of the 48 sputum samples, 25 were positive for MTBC using the GeneXpert MTB/RIF test. Nevertheless, the IS6110 and mtp40 single-step PCR revealed the IS6110 in 27 of the 48 sputum samples, while the mtp40 gene fragment was found in only 17 of them. Furthermore, multiplex PCR assays detected drug-resistant conferring mutations in 21 (77.8%) of the 27 samples with confirmed MTBC DNA, 10 of which contained single drug-resistant conferring mutations towards ethambutol and two towards rifampin, and the remaining nine contained double-resistant mutations for ethambutol and rifampin. In contrast, only five sputum specimens (18.5%) contained drug-resistant MTBC isolates, and two contained mono-drug-resistant MTBC species toward ethambutol and rifampin, respectively, and the remaining three were designated as multi-drug resistant toward both drugs using GeneXpert and phenotypic culture-based drug susceptibility tests. Such discrepancies in the results emphasize the need to develop novel molecular tests that associate with phenotypic non-DNA-based assays to improve the detection of drug-resistant isolates in clinical specimens in future studies.
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Affiliation(s)
- Hassan A. Hemeg
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Hamzah O. Albulushi
- Biology Department, College of Science, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Hani A. Ozbak
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Hamza M. Ali
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Emad K. Alahmadi
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Yahya A. Almutawif
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Sari T. Alhuofie
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Rana A. Alaeq
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Areej A. Alhazmi
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Mustafa A. Najim
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
| | - Ahmed M. Hanafy
- Biology Department, College of Science, Taibah University, Al-Madinah, Kingdom of Saudi Arabia
- Department of Microbiology, Faculty of Science, Ain Shams University, Cairo, Egypt
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Verble K, Hallerman EM, Alexander KA. Urban landscapes increase dispersal, gene flow, and pathogen transmission potential in banded mongoose ( Mungos mungo) in northern Botswana. Ecol Evol 2021; 11:9227-9240. [PMID: 34306619 PMCID: PMC8293740 DOI: 10.1002/ece3.7487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 06/01/2020] [Accepted: 06/04/2020] [Indexed: 11/09/2022] Open
Abstract
Disease transmission can be strongly influenced by the manner in which conspecifics are connected across a landscape and the effects of land use upon these dynamics. In northern Botswana, the territorial and group-living banded mongoose (Mungos mungo) lives across urban and natural landscapes and is infected with a novel Mycobacterium tuberculosis complex pathogen, M. mungi. Using microsatellite markers amplified from DNA derived from banded mongoose fecal and tissue samples (n = 168), we evaluated population genetic structure, individual dispersal, and gene flow for 12 troops. Genetic structure was detectable and moderately strong across groups (F ST = 0.086), with K = 7 being the best-supported number of genetic clusters. Indications of admixture in certain troops suggest formation of new groups through recent fusion events. Differentiation was higher for troops inhabiting natural areas (F ST = 0.102) than for troops in urban landscapes (F ST = 0.081). While this suggests increased levels of gene flow between urban-dwelling troops, the inclusion of a smaller number of study troops from natural land types may have influenced these findings. Of those individuals confirmed infected with M. mungi, the majority (73%, n = 11) were assigned to their natal group which is consistent with previous observations linking lower levels of dispersal with infection. Twenty-one probable dispersing individuals were identified, with all suspected migrants originating from troops within the urban landscape. Findings suggest that urbanized landscapes may increase gene flow and dispersal behavior with a concomitant increase in the risk of pathogen spread. As urban landscapes expand, there is an increasing need to understand how land use and pathogen infection may change wildlife behavior and disease transmission potential.
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Affiliation(s)
- Kelton Verble
- Department of Fish and Wildlife ConservationVirginia TechBlacksburgVAUSA
- Present address:
Department of Biological SciencesUniversity of AlabamaTuscaloosaALUSA
| | - Eric M. Hallerman
- Department of Fish and Wildlife ConservationVirginia TechBlacksburgVAUSA
| | - Kathleen A. Alexander
- Department of Fish and Wildlife ConservationVirginia TechBlacksburgVAUSA
- Chobe Research InstituteCARACALKasaneBotswana
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Allen AR, Ford T, Skuce RA. Does Mycobacterium tuberculosis var. bovis Survival in the Environment Confound Bovine Tuberculosis Control and Eradication? A Literature Review. Vet Med Int 2021; 2021:8812898. [PMID: 33628412 PMCID: PMC7880718 DOI: 10.1155/2021/8812898] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/12/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Bovine tuberculosis (bTB) is one of the globe's most common, multihost zoonoses and results in substantial socioeconomic costs for governments, farming industries, and tax payers. Despite decades of surveillance and research, surprisingly, little is known about the exact mechanisms of transmission. In particular, as a facultative intracellular pathogen, to what extent does survival of the causative agent, Mycobacterium tuberculosis var. bovis (M. bovis), in the environment constitute an epidemiological risk for livestock and wildlife? Due largely to the classical pathology of cattle cases, the received wisdom was that bTB was spread by direct inhalation and exchange of bioaerosols containing droplets laden with bacteria. Other members of the Mycobacterium tuberculosis complex (MTBC) exhibit differing host ranges, an apparent capacity to persist in environmental fomites, and they favour a range of different transmission routes. It is possible, therefore, that infection from environmental sources of M. bovis could be a disease transmission risk. Recent evidence from GPS-collared cattle and badgers in Britain and Ireland suggests that direct transmission by infectious droplets or aerosols may not be the main mechanism for interspecies transmission, raising the possibility of indirect transmission involving a contaminated, shared environment. The possibility that classical pulmonary TB can be simulated and recapitulated in laboratory animal models by ingestion of contaminated feed is a further intriguing indication of potential environmental risk. Livestock and wildlife are known to shed M. bovis onto pasture, soil, feedstuffs, water, and other fomites; field and laboratory studies have indicated that persistence is possible, but variable, under differing environmental conditions. Given the potential infection risk, it is timely to review the available evidence, experimental approaches, and methodologies that could be deployed to address this potential blind spot and control point. Although we focus on evidence from Western Europe, the concepts are widely applicable to other multihost bTB episystems.
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Affiliation(s)
- Adrian R. Allen
- Agri-Food and Biosciences Institute, Veterinary Sciences Division, Bacteriology Branch, Stoney Road Stormont, Belfast BT4 3SD, Northern Ireland, UK
| | - Tom Ford
- Agri-Food and Biosciences Institute, Veterinary Sciences Division, Bacteriology Branch, Stoney Road Stormont, Belfast BT4 3SD, Northern Ireland, UK
| | - Robin A. Skuce
- Agri-Food and Biosciences Institute, Veterinary Sciences Division, Bacteriology Branch, Stoney Road Stormont, Belfast BT4 3SD, Northern Ireland, UK
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Utility of xpert® MTB/RIF ultra assay in the rapid diagnosis of bovine tuberculosis in wildlife and livestock animals from South Africa. Prev Vet Med 2020; 177:104980. [PMID: 32268223 DOI: 10.1016/j.prevetmed.2020.104980] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/14/2020] [Accepted: 03/24/2020] [Indexed: 12/30/2022]
Abstract
Members of the Mycobacterium tuberculosis complex (MTBC) bacteria, mainly Mycobacterium bovis (M. bovis), cause bovine tuberculosis (bTB) in livestock and wildlife animals. Confirmation of the disease is through culture and verification of the causative agent by molecular tests. In this study, we assessed the utility of the Xpert ® MTB/RIF Ultra assay, an automated molecular test originally designed to improve the detection of tuberculosis (TB) and rifampicin resistance in clinical sputum samples of human origin, by conducting a comparative evaluation with a culture based method routinely used at the Onderstepoort Veterinary Research (OVR). A total of 167 samples (tissue, n = 165; pus, n = 1; abscess, n = 1) from different wildlife and livestock animals (from 65 individual animals) were analyzed. Mycobacterium tuberculosis complex species was isolated in 63 (37.72 %) of the 167 samples, and was detected in 79 (47.3 %) of the samples by Xpert ® MTB/RIF Ultra assay. Based on the standard culture test, the diagnostic sensitivity and specificity of the Xpert ® MTB/RIF Ultra assay was found to be 95.24 % and 82 % respectively. All animals that were confirmed bTB positive by culture method were also found to be positive with the Xpert ® MTB/RIF Ultra assay in at least one sample (indicating a 100 % sensitivity of the method at the animal level). Non-tuberculous mycobacteria were isolated in 9 (3.4 %) of the samples analysed and none were detected by Xpert ® MTB/RIF Ultra assay, highlighting that this molecular test is highly specific. Xpert ® MTB/RIF Ultra assay was found to have great potential for the rapid diagnosis of the bTB in animals, hence allowing early intervention by regulatory authorities.
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Larsen MH, Lacourciere K, Parker TM, Kraigsley A, Achkar JM, Adams LB, Dupnik KM, Hall-Stoodley L, Hartman T, Kanipe C, Kurtz SL, Miller MA, Salvador LCM, Spencer JS, Robinson RT. The Many Hosts of Mycobacteria 8 (MHM8): A conference report. Tuberculosis (Edinb) 2020; 121:101914. [PMID: 32279870 PMCID: PMC7428850 DOI: 10.1016/j.tube.2020.101914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/07/2020] [Accepted: 02/09/2020] [Indexed: 12/18/2022]
Abstract
Mycobacteria are important causes of disease in human and animal hosts. Diseases caused by mycobacteria include leprosy, tuberculosis (TB), nontuberculous mycobacteria (NTM) infections and Buruli Ulcer. To better understand and treat mycobacterial disease, clinicians, veterinarians and scientists use a range of discipline-specific approaches to conduct basic and applied research, including conducting epidemiological surveys, patient studies, wildlife sampling, animal models, genetic studies and computational simulations. To foster the exchange of knowledge and collaboration across disciplines, the Many Hosts of Mycobacteria (MHM) conference series brings together clinical, veterinary and basic scientists who are dedicated to advancing mycobacterial disease research. Started in 2007, the MHM series recently held its 8th conference at the Albert Einstein College of Medicine (Bronx, NY). Here, we review the diseases discussed at MHM8 and summarize the presentations on research advances in leprosy, NTM and Buruli Ulcer, human and animal TB, mycobacterial disease comorbidities, mycobacterial genetics and 'omics, and animal models. A mouse models workshop, which was held immediately after MHM8, is also summarized. In addition to being a resource for those who were unable to attend MHM8, we anticipate this review will provide a benchmark to gauge the progress of future research concerning mycobacteria and their many hosts.
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Affiliation(s)
- Michelle H Larsen
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Karen Lacourciere
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA
| | - Tina M Parker
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA
| | - Alison Kraigsley
- Center for Infectious Disease Research and Policy, University of Minnesota, Minneapolis, MN, USA
| | - Jacqueline M Achkar
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Linda B Adams
- Department of Health and Human Services, Health Resources and Services Administration, Healthcare Systems Bureau, National Hansen's Disease Programs, Baton Rouge, LA, USA
| | - Kathryn M Dupnik
- Center for Global Health, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Luanne Hall-Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Travis Hartman
- Center for Global Health, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Carly Kanipe
- Department of Immunobiology, Iowa State University, Ames, IA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA; Bacterial Diseases of Livestock Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA, USA
| | - Sherry L Kurtz
- Laboratory of Mucosal Pathogens and Cellular Immunology, Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Washington, DC, USA
| | - Michele A Miller
- DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Liliana C M Salvador
- Department of Infectious Diseases, University of Georgia, Athens, GA, USA; Institute of Bioinformatics, University of Georgia, Athens, GA, USA; Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - John S Spencer
- Department of Microbiology, Immunology, and Pathology, Mycobacteria Research Laboratories, Colorado State University, Fort Collins, CO, USA
| | - Richard T Robinson
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA.
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Laver PN, Ganswindt A, Ganswindt SB, Alexander KA. Effect of food limitation and reproductive activity on fecal glucocorticoid metabolite levels in banded mongooses. BMC Ecol 2020; 20:12. [PMID: 32070331 PMCID: PMC7027037 DOI: 10.1186/s12898-020-00280-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 02/05/2020] [Indexed: 11/10/2022] Open
Abstract
Background Glucocorticoids mediate responses to perceived stressors, thereby restoring homeostasis. However, prolonged glucocorticoid elevation may cause homeostatic overload. Using extensive field investigations of banded mongoose (Mungos mungo) groups in northern Botswana, we assessed the influence of reproduction, predation risk, and food limitation on apparent homeostatic overload (n=13 groups, 1542 samples from 268 animals). We experimentally manipulated reproduction and regulated food supply in captive mongooses, and compared their glucocorticoid responses to those obtained from free-living groups. Results At the population level, variation in glucocorticoid levels in free-living mongooses was explained by food limitation: fecal organic matter, recent rainfall, and access to concentrated anthropogenic food resources. Soil macrofauna density and reproductive events explained less and predation risk very little variation in glucocorticoid levels. Reproduction and its associated challenges alone (under regulated feeding conditions) increased glucocorticoid levels 19-fold in a captive group. Among free-living groups, glucocorticoid elevation was seasonal (occurring in late dry season or early wet season when natural food resources were less available), but the timing of peak glucocorticoid production was moderated by access to anthropogenic resources (groups with fewer anthropogenic food sources had peaks earlier in dry seasons). Peak months represented 12- and 16-fold increases in glucocorticoids relative to nadir months with some animals exhibiting 100-fold increases. Relative to the captive group nadir, some free-living groups exhibited 60-fold increases in peak glucocorticoid levels with some animals exhibiting up to 800-fold increases. Most of these animals exhibited 1- to 10-fold increases relative to the captive animal peak. Conclusions Banded mongooses exhibit seasonal chronic glucocorticoid elevation, associated primarily with food limitation and secondarily with reproduction. Magnitude and duration of this elevation suggests that this may be maladaptive for some animals, with possible fitness consequences. In late dry season, this population may face a convergence of stressors (food limitation, agonistic encounters at concentrated food resources, evictions, estrus, mate competition, parturition, and predation pressure on pups), which may induce homeostatic overload.
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Affiliation(s)
- Pete N Laver
- Biodiversity and Development Institute, 4 Gunner's Park, Grenville Avenue, Epping 1, Cape Town, 7460, South Africa.
| | - André Ganswindt
- Mammal Research Institute, Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa.,Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.,Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa
| | - Stefanie B Ganswindt
- Mammal Research Institute, Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa.,Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa
| | - Kathleen A Alexander
- Department of Fish and Wildlife Conservation, Virginia Tech, 100 Cheatham Hall, Blacksburg, VA, 24061-0321, USA
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Palmer MV, Thacker TC, Rabideau MM, Jones GJ, Kanipe C, Vordermeier HM, Ray Waters W. Biomarkers of cell-mediated immunity to bovine tuberculosis. Vet Immunol Immunopathol 2019; 220:109988. [PMID: 31846797 DOI: 10.1016/j.vetimm.2019.109988] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 11/15/2019] [Accepted: 11/28/2019] [Indexed: 10/25/2022]
Abstract
Whole blood based assays, particularly interferon gamma (IFN-γ) release assays (IGRAs), are used for the diagnosis of both bovine and human tuberculosis (TB). The aim of the current study was to evaluate a panel of cytokines and chemokines for potential use as diagnostic readouts indicative of Mycobacterium bovis (M. bovis) infection in cattle. A gene expression assay was used to determine the kinetics of the response to M. bovis purified protein derivative and a fusion protein consisting of ESAT-6, CFP10, and Rv3615c upon aerosol infection with ∼104 cfu of M. bovis. The panel of biomarkers included: IFN-γ, CXCL9, CXCL10, CCL2, CCL3, TNF-α, IL-1α, IL-1β, IL-1Ra, IL-22, IL-21 and IL-13. Protein levels of IFN-γ, CXCL9, and CXCL10 were determined by ELISA. Findings suggest that CXCL9, CXCL10, IL-21, IL-13, and several acute phase cytokines may be worth pursuing as diagnostic biomarkers of M. bovis infection in cattle.
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Affiliation(s)
- Mitchell V Palmer
- National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture (USDA), Ames, Iowa, USA.
| | - Tyler C Thacker
- National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture (USDA), Ames, Iowa, USA
| | - Meaghan M Rabideau
- National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture (USDA), Ames, Iowa, USA
| | - Gareth J Jones
- TB Immunology and Vaccinology, Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surry UK
| | - Carly Kanipe
- National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture (USDA), Ames, Iowa, USA; Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - H Martin Vordermeier
- TB Immunology and Vaccinology, Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surry UK
| | - W Ray Waters
- National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture (USDA), Ames, Iowa, USA
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Mongoose ( Herpestes auropunctatus) May Not Be Reservoir Hosts for Mycobacterium bovis in Fiji Despite High Population Density and Direct Contact with Cattle. Vet Sci 2019; 6:vetsci6040085. [PMID: 31652969 PMCID: PMC6958361 DOI: 10.3390/vetsci6040085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 11/29/2022] Open
Abstract
The presence of a wildlife reservoir for Mycobacterium bovis complicates the eradication of bovine tuberculosis (BTB) from domestic cattle populations. For the BTB eradication program in Fiji, there is concern about the small Indian mongoose (Herpestes auropunctatus), which is overabundant and in direct contact with cattle. Consequently, a survey of mongooses trapped on three BTB affected dairy farms led to necropsy of 85 mongooses during January–February 2017. Thirty (35%) mongooses had gross pathological changes including possible granulomas detected at necropsy, and tissues from these animals were taken for histopathological examination. Granulomatous lesions were present in 53% of animals examined histopathologically but acid-fast bacilli were not observed and the majority of lesions in lung and kidney were associated with the nematodes Pulmostrongylus herpestis and Capillaria sp., respectively. Nevertheless, assuming test sensitivity of 35% for the current study, from this sample of 85 mongooses it can be concluded with 95% confidence that if present in the mongoose population susceptible to trapping, M. bovis prevalence was ≤10%. The prevalence of intercurrent lesions raised concerns about gross pathology as a screening test for M. bovis infection in mongooses in Fiji, and therefore pathogen detection methods such as bacterial culture and direct tissue PCR are recommended for future surveys. These are needed to completely rule out the mongoose as a reservoir host for M. bovis in Fiji.
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Fieweger RA, Wilburn KM, VanderVen BC. Comparing the Metabolic Capabilities of Bacteria in the Mycobacterium tuberculosis Complex. Microorganisms 2019; 7:E177. [PMID: 31216777 PMCID: PMC6617402 DOI: 10.3390/microorganisms7060177] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/10/2019] [Accepted: 06/15/2019] [Indexed: 02/06/2023] Open
Abstract
Pathogenic mycobacteria are known for their ability to maintain persistent infections in various mammals. The canonical pathogen in this genus is Mycobacterium tuberculosis and this bacterium is particularly successful at surviving and replicating within macrophages. Here, we will highlight the metabolic processes that M. tuberculosis employs during infection in macrophages and compare these findings with what is understood for other pathogens in the M. tuberculosis complex.
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Affiliation(s)
- Rachael A Fieweger
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
| | - Kaley M Wilburn
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
| | - Brian C VanderVen
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
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