1
|
Li L, Maboni G, Lack A, Gomez DE. Nontuberculous Mycobacteria in Horses: A Narrative Review. Vet Sci 2023; 10:442. [PMID: 37505847 PMCID: PMC10384023 DOI: 10.3390/vetsci10070442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023] Open
Abstract
Nontuberculous mycobacteria (NTM) infections are increasing in human and veterinary medicine. Although horses were initially thought to be resistant to NTM infection, reports of horses suffering from gastrointestinal, respiratory, and reproductive diseases associated with NTM have increased in the last few decades. The aim of this literature review is to summarize the mycobacteria species found in horses, describe clinical manifestations, diagnostic and treatment approaches, and public health concerns of NTM infection in horses. Clinical manifestations of NTM in horses include pulmonary disease, lymphadenitis, soft tissue, bone infections, and disseminated disease. NTM are also linked to granulomatous enteritis, placentitis, and abortions. Currently, diagnostic methods for NTM are limited and include acid-fast microscopy, bacterial cultures, species-specific PCR assays, and gene sequencing. In humans, NTM treatment guidelines are available, but their application appears inadequate and inconsistent. In horses, treatment guidelines for NTM infections are not available. NTM are a serious public health threat as 70% of people with untreated acquired immunodeficiency syndrome (AIDS) have a chronic pulmonary disease caused by NTM. Thus, it is essential that we gain a better understanding of NTM infections in horses and their zoonotic potential.
Collapse
Affiliation(s)
- Lynna Li
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Grazieli Maboni
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Amy Lack
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Diego E Gomez
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada
| |
Collapse
|
2
|
Vandelannoote K, Buultjens AH, Porter JL, Velink A, Wallace JR, Blasdell KR, Dunn M, Boyd V, Fyfe JAM, Tay EL, Johnson PDR, Windecker SM, Golding N, Stinear TP. Statistical modeling based on structured surveys of Australian native possum excreta harboring Mycobacterium ulcerans predicts Buruli ulcer occurrence in humans. eLife 2023; 12:e84983. [PMID: 37057888 PMCID: PMC10154024 DOI: 10.7554/elife.84983] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 04/13/2023] [Indexed: 04/15/2023] Open
Abstract
Background Buruli ulcer (BU) is a neglected tropical disease caused by infection of subcutaneous tissue with Mycobacterium ulcerans. BU is commonly reported across rural regions of Central and West Africa but has been increasing dramatically in temperate southeast Australia around the major metropolitan city of Melbourne, with most disease transmission occurring in the summer months. Previous research has shown that Australian native possums are reservoirs of M. ulcerans and that they shed the bacteria in their fecal material (excreta). Field surveys show that locales where possums harbor M. ulcerans overlap with human cases of BU, raising the possibility of using possum excreta surveys to predict the risk of disease occurrence in humans. Methods We thus established a highly structured 12 month possum excreta surveillance program across an area of 350 km2 in the Mornington Peninsula area 70 km south of Melbourne, Australia. The primary objective of our study was to assess using statistical modeling if M. ulcerans surveillance of possum excreta provided useful information for predicting future human BU case locations. Results Over two sampling campaigns in summer and winter, we collected 2,282 possum excreta specimens of which 11% were PCR positive for M. ulcerans-specific DNA. Using the spatial scanning statistical tool SaTScan, we observed non-random, co-correlated clustering of both M. ulcerans positive possum excreta and human BU cases. We next trained a statistical model with the Mornington Peninsula excreta survey data to predict the future likelihood of human BU cases occurring in the region. By observing where human BU cases subsequently occurred, we show that the excreta model performance was superior to a null model trained using the previous year's human BU case incidence data (AUC 0.66 vs 0.55). We then used data unseen by the excreta-informed model from a new survey of 661 possum excreta specimens in Geelong, a geographically separate BU endemic area to the southwest of Melbourne, to prospectively predict the location of human BU cases in that region. As for the Mornington Peninsula, the excreta-based BU prediction model outperformed the null model (AUC 0.75 vs 0.50) and pinpointed specific locations in Geelong where interventions could be deployed to interrupt disease spread. Conclusions This study highlights the One Health nature of BU by confirming a quantitative relationship between possum excreta shedding of M. ulcerans and humans developing BU. The excreta survey-informed modeling we have described will be a powerful tool for the efficient targeting of public health responses to stop BU. Funding This research was supported by the National Health and Medical Research Council of Australia and the Victorian Government Department of Health (GNT1152807 and GNT1196396).
Collapse
Affiliation(s)
- Koen Vandelannoote
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of MelbourneMelbourneAustralia
- Bacterial Phylogenomics Group, Institut Pasteur du CambodgePhnom PenhCambodia
| | - Andrew H Buultjens
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of MelbourneMelbourneAustralia
| | - Jessica L Porter
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of MelbourneMelbourneAustralia
| | - Anita Velink
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of MelbourneMelbourneAustralia
| | - John R Wallace
- Department of Biology, Millersville UniversityMillersvilleUnited States
| | - Kim R Blasdell
- Health and Biosecurity, Commonwealth Scientific and Industrial Research OrganisationGeelongAustralia
| | - Michael Dunn
- Health and Biosecurity, Commonwealth Scientific and Industrial Research OrganisationGeelongAustralia
| | - Victoria Boyd
- Health and Biosecurity, Commonwealth Scientific and Industrial Research OrganisationGeelongAustralia
| | - Janet AM Fyfe
- Victorian Infectious Diseases Reference Laboratory, Doherty Institute for Infection and ImmunityMelbourneAustralia
| | - Ee Laine Tay
- Health Protection branch, Department of HealthVictoriaAustralia
| | - Paul DR Johnson
- North Eastern Public Health Unit (NEPHU), Austin HealthMelbourneAustralia
| | - Saras M Windecker
- School of Ecosystem and Forest Sciences, University of MelbourneMelbourneAustralia
| | - Nick Golding
- Telethon Kids Institute, Perth Children’s HospitalNedlandsAustralia
- Curtin School of Population Health, Curtin UniversityBentleyAustralia
- Melbourne School of Population and Global Health, University of MelbourneMelbourneAustralia
| | - Timothy P Stinear
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of MelbourneMelbourneAustralia
| |
Collapse
|
3
|
Blasdell KR, McNamara B, O’Brien DP, Tachedjian M, Boyd V, Dunn M, Mee PT, Clayton S, Gaburro J, Smith I, Gibney KB, Tay EL, Hobbs EC, Waidyatillake N, Lynch SE, Stinear TP, Athan E. Environmental risk factors associated with the presence of Mycobacterium ulcerans in Victoria, Australia. PLoS One 2022; 17:e0274627. [PMID: 36099259 PMCID: PMC9469944 DOI: 10.1371/journal.pone.0274627] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/01/2022] [Indexed: 11/18/2022] Open
Abstract
In recent years reported cases of Buruli ulcer, caused by Mycobacterium ulcerans, have increased substantially in Victoria, Australia, with the epidemic also expanding geographically. To develop an understanding of how M. ulcerans circulates in the environment and transmits to humans we analyzed environmental samples collected from 115 properties of recent Buruli ulcer cases and from 115 postcode-matched control properties, for the presence of M. ulcerans. Environmental factors associated with increased odds of M. ulcerans presence at a property included certain native plant species and native vegetation in general, more alkaline soil, lower altitude, the presence of common ringtail possums (Pseudocheirus peregrinus) and overhead powerlines. However, only overhead powerlines and the absence of the native plant Melaleuca lanceolata were associated with Buruli ulcer case properties. Samples positive for M. ulcerans were more likely to be found at case properties and were associated with detections of M. ulcerans in ringtail possum feces, supporting the hypothesis that M. ulcerans is zoonotic, with ringtail possums the strongest reservoir host candidate. However, the disparity in environmental risk factors associated with M. ulcerans positive properties versus case properties indicates the involvement of human behavior or the influence of other environmental factors in disease acquisition that requires further study.
Collapse
Affiliation(s)
- Kim R. Blasdell
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
- * E-mail:
| | - Bridgette McNamara
- Department of Infectious Diseases, Barwon Health, Geelong, Victoria, Australia
- Centre of Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Daniel P. O’Brien
- Department of Infectious Diseases, Barwon Health, Geelong, Victoria, Australia
- Department of Health, Victorian State Government, Melbourne, Victoria, Australia
| | - Mary Tachedjian
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
| | - Victoria Boyd
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
| | - Michael Dunn
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
| | - Peter T. Mee
- Agriculture Victoria Research, AgriBio Centre for AgriBiosciences, Bundoora, Victoria, Australia
| | - Simone Clayton
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
| | - Julie Gaburro
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia
| | - Ina Smith
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Canberra, Australian Capital Territory, Australia
| | - Katherine B. Gibney
- Department of Infectious Diseases, Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Ee Laine Tay
- Department of Health, Victorian State Government, Melbourne, Victoria, Australia
| | - Emma C. Hobbs
- Department of Infectious Diseases, Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | | | - Stacey E. Lynch
- Agriculture Victoria Research, AgriBio Centre for AgriBiosciences, Bundoora, Victoria, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Eugene Athan
- Department of Infectious Diseases, Barwon Health, Geelong, Victoria, Australia
- Geelong Centre for Emerging Infectious Diseases, Geelong, Victoria, Australia
| |
Collapse
|
4
|
Loukil A, Lalaoui R, Bogreau H, Regoui S, Drancourt M, Hammoudi N. Mycobacterium ulcerans Experimental Dormancy. Am J Trop Med Hyg 2022; 107:tpmd211327. [PMID: 35405654 PMCID: PMC9294675 DOI: 10.4269/ajtmh.21-1327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/15/2022] [Indexed: 11/07/2022] Open
Abstract
Whether Mycobacterium ulcerans, the etiological agent of Buruli ulcer in numerous tropical countries, would exist in a dormant state as reported for closely related Mycobacterium species, has not been established. Six M. ulcerans strains were exposed to a progressive depletion in oxygen for 2 months, using the Wayne model of dormancy previously described for M. tuberculosis, and further examined by microscopy after staining of dynamic, dormant, and dead mycobacteria (DDD staining), microcalorimetry and subculture in the presence of dead and replicative M. ulcerans as controls. Mycobacterium ulcerans CU001 strain died during the progressive oxygen depletion and four of five remaining strains exhibited Nile red-stained intracellular lipid droplets and a 14- to 20-day regrowth when exposed to ambient air, consistent with dormancy. A fifth M. ulcerans 19423 strain stained negative in DDD staining and slowly regrew in 27 days. Three tested M. ulcerans strains yielded microcalorimetric pattern similar to that of the negative (dead) homologous controls, differing from that of the homologous positive (replicative) controls. The relevance of these experimental observations, suggesting a previously unreported dormancy state of M. ulcerans, warrants further investigations in the natural ecological niches where M. ulcerans thrive as well as in Buruli ulcer lesions.
Collapse
Affiliation(s)
- Ahmed Loukil
- Aix Marseille Univ., IRD, APHM, MEPHI, Marseille, France
| | - Rym Lalaoui
- Aix Marseille Univ., IRD, APHM, MEPHI, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
| | - Hervé Bogreau
- IHU-Méditerranée Infection, Marseille, France
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, IHU Méditerranée Infection, Marseille, France
- Aix Marseille Univ., IRD, SSA, AP-HM, VITROME, Marseille, France
| | | | - Michel Drancourt
- Aix Marseille Univ., IRD, APHM, MEPHI, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
| | - Nassim Hammoudi
- Aix Marseille Univ., IRD, APHM, MEPHI, Marseille, France
- IHU-Méditerranée Infection, Marseille, France
| |
Collapse
|
5
|
Receveur JP, Bauer A, Pechal JL, Picq S, Dogbe M, Jordan HR, Rakestraw AW, Fast K, Sandel M, Chevillon C, Guégan JF, Wallace JR, Benbow ME. A need for null models in understanding disease transmission: the example of Mycobacterium ulcerans (Buruli ulcer disease). FEMS Microbiol Rev 2022; 46:fuab045. [PMID: 34468735 PMCID: PMC8767449 DOI: 10.1093/femsre/fuab045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 08/12/2021] [Indexed: 01/19/2023] Open
Abstract
Understanding the interactions of ecosystems, humans and pathogens is important for disease risk estimation. This is particularly true for neglected and newly emerging diseases where modes and efficiencies of transmission leading to epidemics are not well understood. Using a model for other emerging diseases, the neglected tropical skin disease Buruli ulcer (BU), we systematically review the literature on transmission of the etiologic agent, Mycobacterium ulcerans (MU), within a One Health/EcoHealth framework and against Hill's nine criteria and Koch's postulates for making strong inference in disease systems. Using this strong inference approach, we advocate a null hypothesis for MU transmission and other understudied disease systems. The null should be tested against alternative vector or host roles in pathogen transmission to better inform disease management. We propose a re-evaluation of what is necessary to identify and confirm hosts, reservoirs and vectors associated with environmental pathogen replication, dispersal and transmission; critically review alternative environmental sources of MU that may be important for transmission, including invertebrate and vertebrate species, plants and biofilms on aquatic substrates; and conclude with placing BU within the context of other neglected and emerging infectious diseases with intricate ecological relationships that lead to disease in humans, wildlife and domestic animals.
Collapse
Affiliation(s)
- Joseph P Receveur
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
| | - Alexandra Bauer
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
| | - Jennifer L Pechal
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
| | - Sophie Picq
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
| | - Magdalene Dogbe
- Department of Biological Sciences, Mississippi State University, Starkville, MS, USA
| | - Heather R Jordan
- Department of Biological Sciences, Mississippi State University, Starkville, MS, USA
| | - Alex W Rakestraw
- Department of Biological and Environmental Sciences, The University of West Alabama, Livingston, AL, USA
| | - Kayla Fast
- Department of Biological and Environmental Sciences, The University of West Alabama, Livingston, AL, USA
| | - Michael Sandel
- Department of Biological and Environmental Sciences, The University of West Alabama, Livingston, AL, USA
| | - Christine Chevillon
- Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier (UM), Centre National de la Recherche Scientifique (CNRS), Institut pour la Recherche et le Développement, Montpellier, France
| | - Jean-François Guégan
- Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier (UM), Centre National de la Recherche Scientifique (CNRS), Institut pour la Recherche et le Développement, Montpellier, France
- UMR Animal, santé, territoires, risques et écosystèmes, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Centre de coopération internationale en recherche agronomique pour le développement (Cirad), Université de Montpellier (UM), Montpellier, France
| | - John R Wallace
- Department of Biology, Millersville University, Millersville, PA, USA
| | - M Eric Benbow
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
- Ecology, Evolution and Behavior Program, Michigan State University, East Lansing, MI, USA
- AgBioResearch, Michigan State University, East Lansing, MI, USA
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, MI, USA
| |
Collapse
|
6
|
Muleta AJ, Lappan R, Stinear TP, Greening C. Understanding the transmission of Mycobacterium ulcerans: A step towards controlling Buruli ulcer. PLoS Negl Trop Dis 2021; 15:e0009678. [PMID: 34437549 PMCID: PMC8389476 DOI: 10.1371/journal.pntd.0009678] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of Buruli ulcer, a rare but chronic debilitating skin and soft tissue disease found predominantly in West Africa and Southeast Australia. While a moderate body of research has examined the distribution of M. ulcerans, the specific route(s) of transmission of this bacterium remain unknown, hindering control efforts. M. ulcerans is considered an environmental pathogen given it is associated with lentic ecosystems and human-to-human spread is negligible. However, the pathogen is also carried by various mammals and invertebrates, which may serve as key reservoirs and mechanical vectors, respectively. Here, we examine and review recent evidence from these endemic regions on potential transmission pathways, noting differences in findings between Africa and Australia, and summarising the risk and protective factors associated with Buruli ulcer transmission. We also discuss evidence suggesting that environmental disturbance and human population changes precede outbreaks. We note five key research priorities, including adoption of One Health frameworks, to resolve transmission pathways and inform control strategies to reduce the spread of Buruli ulcer. Buruli ulcer is a debilitating skin and soft tissue disease characterised by large ulcerative wounds that are treated with antibiotics or with adjunctive surgery for advanced cases. Found predominantly in West Africa and Southeast Australia, the causative agent is the environmental bacterial pathogen Mycobacterium ulcerans. Lack of understanding of transmission pathways, combined with the absence of a vaccine, has hindered efforts to control the spread of M. ulcerans. Here, in order to identify probable transmission pathways and inform future studies, we review literature linking M. ulcerans to environmental reservoirs, mammalian hosts, and potential invertebrate vectors. We also summarise factors and behaviours that reduce the risk of developing Buruli ulcer, to inform effective prevention strategies and further shed light on transmission pathways.
Collapse
Affiliation(s)
- Anthony J. Muleta
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Rachael Lappan
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
| | - Chris Greening
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
- Centre to Impact AMR, Monash University, Melbourne, Australia
- * E-mail:
| |
Collapse
|
7
|
Blume GR, Eloi RSA, Oliveira LB, Moraes ELSC, Seeger MG, Cargnelutti JF, de Sant'Ana FJF. Non-tuberculous Mycobacterial Granulomatous Dermatitis in an African Pygmy Hedgehog (Atelerix albiventris). J Comp Pathol 2020; 182:22-26. [PMID: 33494903 DOI: 10.1016/j.jcpa.2020.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/25/2020] [Accepted: 11/04/2020] [Indexed: 11/26/2022]
Abstract
A 2-year-old female African pygmy hedgehog (Atelerix albiventris) with a cutaneous nodular lesion on the dorsal surface of the right forelimb was presented for clinical examination. Histopathological findings included granulomatous dermatitis with extensive necrosis. Long and slender acid-fast bacilli were seen within the cytoplasm of macrophages and in extracellular spaces. Bacteriological culture of skin revealed acid-fast bacilli and non-tuberculous mycobacterial infection was confirmed by gene sequencing and identity analysis using the BLAST tool. To our knowledge, this is the first report of non-tuberculous granulomatous dermatitis in hedgehogs.
Collapse
Affiliation(s)
- Guilherme R Blume
- Laboratório de Diagnóstico Patológico Veterinário, Universidade de Brasília, Brasilia
| | - Rômulo S A Eloi
- Laboratório Histopato-Análise Anatomopatológica Veterinária, Brasilia
| | | | - Elber L S C Moraes
- Clínica Veterinária Mundo Silvestre, Brasília, Distrito Federal, Brasilia
| | - Marlane G Seeger
- Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - Juliana F Cargnelutti
- Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil; Laboratório de Diagnóstico Patológico Veterinário, Universidade de Brasília, Brasilia
| | | |
Collapse
|
8
|
The diversity of mycolactone-producing mycobacteria. Microb Pathog 2020; 149:104362. [PMID: 32702376 DOI: 10.1016/j.micpath.2020.104362] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/22/2020] [Indexed: 02/08/2023]
Abstract
Mycolactone-producing mycobacteria (MPM) form an intriguing group of environmental opportunistic pathogens of mammals and human patients in whom they cause cutaneous and subcutaneous ulcers known as "Buruli ulcer" when they occur in humans. We reviewed whole genome sequence data and ecological and phenotypic characteristics from 44 MPMs and closely related Mycobacterium marinum. This analysis indicated that all the 24 M. marinum isolates were delineated into seven taxa and our comprehensive, polyphasic taxonomic approach led to the proposal of delineating M. marinum genomospecies, 01-07. Likewise, 20 MPMs isolates were delineated into seven additional M. ulcerans genomospecies, 01-07. A taxonomic card explaining the ecology, hosts of isolation and the plasmid harboured is provided for each taxon.
Collapse
|
9
|
Chung J, Ince D, Ford BA, Wanat KA. Cutaneous Infections Due to Nontuberculosis Mycobacterium: Recognition and Management. Am J Clin Dermatol 2018; 19:867-878. [PMID: 30168084 DOI: 10.1007/s40257-018-0382-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Nontuberculous mycobacteria (NTM) are a diverse group of organisms that are ubiquitous in the environment, and the incidence of cutaneous infections due to NTM has been steadily increasing. Cutaneous infections due to NTM can be difficult to diagnose, due to their wide spectrum of clinical presentations and histopathological findings that are often nonspecific. A variety of modalities including tissue culture and polymerase chain reaction (PCR) assays may be necessary to identify the organism. Treatment can also be challenging, as it can depend on multiple factors, including the causative organism, the patient's immunological status, and the extent of disease involvement. In this review, we discuss the common presentations of cutaneous NTM infections, diagnostic tools, and treatment recommendations. A multi-disciplinary approach that involves good communication between the clinician, the histopathologist, the microbiologist, and infectious disease specialists can help lead to successful diagnosis and management.
Collapse
Affiliation(s)
- Jina Chung
- Department of Dermatology, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Dilek Ince
- Division of Infectious Disease, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Bradley A Ford
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Karolyn A Wanat
- Department of Dermatology, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
| |
Collapse
|
10
|
Otuh PI, Soyinka FO, Ogunro BN, Akinseye V, Nwezza EE, Iseoluwa-Adelokiki AO, Adeyemo OK. Perception and incidence of Buruli ulcer in Ogun State, South West Nigeria: intensive epidemiological survey and public health intervention recommended. Pan Afr Med J 2018; 29:166. [PMID: 30050630 PMCID: PMC6057600 DOI: 10.11604/pamj.2018.29.166.10110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 02/13/2018] [Indexed: 10/31/2022] Open
Abstract
Introduction Buruli ulcer (BU) is a highly ranked neglected tropical disease (NTD) of global health importance with increasing incidence in sub-Saharan Africa yet there is paucity of information on the epidemiology of BU in Nigeria. Incidentally, highly BU endemic Benin Republic shares proximity with Nigeria. This study was carried out to establish presence of BU and ascertain the level of BU perception among rural populace in Ogun State, south-west Nigeria. Methods Secondary data (2009-2012) on incidence of BU was collected from a reference hospital. A cross-sectional survey using structured questionnaire administered to rural people and healthcare practitioners was conducted in three purposively chosen Local Government Areas (LGAs) in Ogun State based on unpublished reports of BU presence. Results Data collected revealed 27 hospital confirmed BU cases between 2009-2012 across four LGAs (Obafemi Owode, Abeokuta North, Yewa North and Yewa South) while 14%(21/150) chronic ulcers (suspected to be BU) were discovered during the cross-sectional survey carried out in Odeda, Yewa South and North LGAs. Healthcare practitioners 63.6% (42/66) and 54.7% (82/150) rural people demonstrated poor level of BU perception respectively. Conclusion This study provides evidence that BU exists in Ogun State and evaluates the poor perception that the affected rural populace has on the disease. This pilot study presents baseline information on BU in a rural setting in Ogun State South-west Nigeria hence the vital need for prompt public health involvement and further research on the epidemiology of BU.
Collapse
Affiliation(s)
- Patricia Ihuaku Otuh
- Department of Veterinary Public Health and Preventive Medicine, University Of Ibadan, Ibadan, Oyo state, Nigeria.,Veterinary Teaching Hospital, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Festus Olukayode Soyinka
- Ogun State Tuberculosis, Leprosy and Buruli Ulcer Control Programme, Ministry of Health, Abeokuta, Ogun State, Nigeria
| | - Bamidele Nyemike Ogunro
- Department of Veterinary Public Health and Preventive Medicine, University Of Ibadan, Ibadan, Oyo state, Nigeria.,Veterinary Teaching Hospital, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Victor Akinseye
- Veterinary Teaching Hospital, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Elebe Emmanuel Nwezza
- Department of Mathematics/Computer Science/Statistics and informatics, Federal University Ndufu Alike Ikwo, Ebonyi State, Nigeria
| | | | - Olanike Kudirat Adeyemo
- Department of Veterinary Public Health and Preventive Medicine, University Of Ibadan, Ibadan, Oyo state, Nigeria
| |
Collapse
|
11
|
Djouaka R, Zeukeng F, Bigoga JD, Kakou-Ngazoa SE, Akoton R, Tchigossou G, Coulibaly DN, Tchebe SJE, Aboubacar S, Nguepdjo CN, Tossou E, Adeoti R, Ngo Nsonga TM, Akpo Y, Djegbe I, Tamo M, Mbacham WF, Ablordey A. Domestic animals infected with Mycobacterium ulcerans-Implications for transmission to humans. PLoS Negl Trop Dis 2018; 12:e0006572. [PMID: 29965961 PMCID: PMC6044547 DOI: 10.1371/journal.pntd.0006572] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 07/13/2018] [Accepted: 05/30/2018] [Indexed: 11/18/2022] Open
Abstract
Background The environmental pathogen, Mycobacterium ulcerans (MU) can infect both humans and animals and cause Buruli ulcer (BU) disease. However, its mode(s) of transmission from the colonized environment to human/animal hosts remain unclear. In Australia, MU can infect both wildlife and domestic mammals. Till date, BU-like lesions have only been reported in wildlife in Africa. This warrants a thorough assessment of possible MU in domestic animals in Africa. Here, we screened roaming domesticated animals that share the human microhabitat in two different BU endemic sites, Sedje-Denou in Benin and Akonolinga in Cameroon, for MU lesions. Methodology/Principal findings We screened roaming mammals and birds across 3 endemic villages of Sedje-Denou in Southern Benin and 6 endemic villages of Akonolinga in Cameroon. After approval from relevant authorities, specimens (wound swabs and tissue fragments) were collected from animals with open or active lesion and systematically screened to detect the presence of MU though the diagnostic DNA targets IS2404, IS2606 and KR-B. Out of 397 animals surveyed in Akonolinga, 44 (11.08%) carried skin lesions and all were negative for MU DNA. For Sedje-Denou, only 25 (6.93%) out of 361 animals surveyed carried external skin lesions of which 2 (8%) were positive for MU DNA targets. These MU infected lesions were found in two different villages on a goat (abdominal part) and on a dog (nape area of the neck). Source-tracking of MU isolates within infected animal lesions was performed using VNTR genotyping and further confirmed with sequencing. One MU VNTR genotype (Z) was successfully typed from the goat lesion. The evolutionary history inferred from sequenced data revealed a clustering of animal MU isolates within isolates from human lesions. Conclusion/Significance This study describes the first report of two MU infected lesions in domestic animals in Africa. Their DNA sequence analyses show close relationship to isolates from human cases. It suggests that MU infection should be suspected in domestic hosts and these could play a role in transmission. The findings further support the hypothesis that MU is a ubiquitous environmental pathogen found in endemic areas, and probably involved in a multiple transmission pathway. Buruli ulcer (BU) remains a major Public Health problem in rural communities in sub-Saharan Africa. There are several reports of the occurrence of BU in Wildlife as well as domestic animals in Australia leading to the suggestion that animals may play a role in the transmission of MU to humans. Report of BU in animals is however scanty in Africa and no significant link has been made between BU in humans and animals. BU-like lesions were investigated in 397 and 361 roaming domestic animals respectively from Sedje-Denou and Akonolinga. Wound swabs, and tissue fragments were collected from animals with active lesions. Overall, 2 (8%) type I (<5 cm) animal lesions (localized on the abdominal part of a goat and the nape area of a dog) were colonized by MU in Benin. MU VNTR genotypes Z (4, 1, 2, 2) and C- (3, 1, 2, 0) were identified in the lesions of the goat and dog respectively. Significant homology was found between orthologous sequences of MU strains infecting animals and humans. The evolutionary history inferred from sequenced data revealed a clustering of animal MU isolates within isolates from human lesions. New reservoirs of MU were found through this study and allowed to a new interpretation of the life cycle of this mycobacterium from the risk environment to humans in Africa.
Collapse
Affiliation(s)
- Rousseau Djouaka
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
| | - Francis Zeukeng
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
- Faculty of Science, Department of Biochemistry, University of Yaoundé I, Yaoundé, Cameroon
- * E-mail:
| | - Jude Daiga Bigoga
- Faculty of Science, Department of Biochemistry, University of Yaoundé I, Yaoundé, Cameroon
| | - Solange E. Kakou-Ngazoa
- Department of Technics and Technology, Platform of Molecular Biology, Pasteur Institute Abidjan, Abidjan, Côte d’Ivoire
| | - Romaric Akoton
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
- University of Abomey-Calavi, Faculty of Science and Technics, Calavi, Benin
| | - Genevieve Tchigossou
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
- University of Abomey-Calavi, Faculty of Science and Technics, Calavi, Benin
| | - David N’golo Coulibaly
- Department of Technics and Technology, Platform of Molecular Biology, Pasteur Institute Abidjan, Abidjan, Côte d’Ivoire
| | | | - Sylla Aboubacar
- Department of Technics and Technology, Platform of Molecular Biology, Pasteur Institute Abidjan, Abidjan, Côte d’Ivoire
| | | | - Eric Tossou
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
- University of Abomey-Calavi, Faculty of Science and Technics, Calavi, Benin
| | - Razack Adeoti
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
| | | | - Yao Akpo
- Faculty of Agronomy, University of Parakou, Laboratory of Ecology, Health and Animal Production (LESPA), Parakou, Bénin
| | - Innocent Djegbe
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
| | - Manuele Tamo
- The AgroEcoHealth Platform, International Institute of Tropical Agriculture (IITA), Cotonou, Bénin
| | - Wilfred Fon Mbacham
- Faculty of Science, Department of Biochemistry, University of Yaoundé I, Yaoundé, Cameroon
| | - Anthony Ablordey
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana
| |
Collapse
|
12
|
Singh A, McBride WJH, Govan B, Pearson M. Potential Animal Reservoir of Mycobacterium ulcerans: A Systematic Review. Trop Med Infect Dis 2018; 3:tropicalmed3020056. [PMID: 30274452 PMCID: PMC6073983 DOI: 10.3390/tropicalmed3020056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/10/2018] [Accepted: 05/24/2018] [Indexed: 11/16/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of Buruli ulcer, also known in Australia as Daintree ulcer or Bairnsdale ulcer. This destructive skin disease is characterized by extensive and painless necrosis of the skin and soft tissue with the formation of large ulcers, commonly on the leg or arm. To date, 33 countries with tropical, subtropical and temperate climates in Africa, the Americas, Asia and the Western Pacific have reported cases of Buruli ulcer. The disease is rarely fatal, although it may lead to permanent disability and/or disfigurement if not treated appropriately or in time. It is the third most common mycobacterial infection in the world after tuberculosis and leprosy. The precise mode of transmission of M. ulcerans is yet to be elucidated. Nevertheless, it is possible that the mode of transmission varies with different geographical areas and epidemiological settings. The knowledge about the possible routes of transmission and potential animal reservoirs of M. ulcerans is poorly understood and still remains patchy. Infectious diseases arise from the interaction of agent, host and environment. The majority of emerging or remerging infectious disease in human populations is spread by animals: either wildlife, livestock or pets. Animals may act as hosts or reservoirs and subsequently spread the organism to the environment or directly to the human population. The reservoirs may or may not be the direct source of infection for the hosts; however, they play a major role in maintenance of the organism in the environment, and in the mode of transmission. This remains valid for M. ulcerans. Possums have been suggested as one of the reservoir of M. ulcerans in south-eastern Australia, where possums ingest M. ulcerans from the environment, amplify them and shed the organism through their faeces. We conducted a systematic review with selected key words on PubMed and INFORMIT databases to aggregate available published data on animal reservoirs of M. ulcerans around the world. After certain inclusion and exclusion criteria were implemented, a total of 17 studies was included in the review. A variety of animals around the world e.g., rodents, shrews, possums (ringtail and brushtail), horses, dogs, alpacas, koalas and Indian flap-shelled turtles have been recorded as being infected with M. ulcerans. The majority of studies included in this review identified animal reservoirs as predisposing to the emergence and reemergence of M. ulcerans infection. Taken together, from the selected studies in this systematic review, it is clear that exotic wildlife and native mammals play a significant role as reservoirs for M. ulcerans.
Collapse
Affiliation(s)
- Avishek Singh
- Cairns Clinical School, College of Medicine and Dentistry, James Cook University, Cairns City, QLD 4870, Australia.
| | - William John Hannan McBride
- Cairns Clinical School, College of Medicine and Dentistry, James Cook University, Cairns City, QLD 4870, Australia.
| | - Brenda Govan
- College of Public Health, Medical & Vet Sciences, James Cook University, Townsville, QLD 4811, Australia.
| | - Mark Pearson
- Australian Institute of Tropical Health & Medicine, James Cook University, Smithfield, QLD 4878, Australia.
| |
Collapse
|
13
|
Buruli Ulcer, a Prototype for Ecosystem-Related Infection, Caused by Mycobacterium ulcerans. Clin Microbiol Rev 2017; 31:31/1/e00045-17. [PMID: 29237707 DOI: 10.1128/cmr.00045-17] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Buruli ulcer is a noncontagious disabling cutaneous and subcutaneous mycobacteriosis reported by 33 countries in Africa, Asia, Oceania, and South America. The causative agent, Mycobacterium ulcerans, derives from Mycobacterium marinum by genomic reduction and acquisition of a plasmid-borne, nonribosomal cytotoxin mycolactone, the major virulence factor. M. ulcerans-specific sequences have been readily detected in aquatic environments in food chains involving small mammals. Skin contamination combined with any type of puncture, including insect bites, is the most plausible route of transmission, and skin temperature of <30°C significantly correlates with the topography of lesions. After 30 years of emergence and increasing prevalence between 1970 and 2010, mainly in Africa, factors related to ongoing decreasing prevalence in the same countries remain unexplained. Rapid diagnosis, including laboratory confirmation at the point of care, is mandatory in order to reduce delays in effective treatment. Parenteral and potentially toxic streptomycin-rifampin is to be replaced by oral clarithromycin or fluoroquinolone combined with rifampin. In the absence of proven effective primary prevention, avoiding skin contamination by means of clothing can be implemented in areas of endemicity. Buruli ulcer is a prototype of ecosystem pathology, illustrating the impact of human activities on the environment as a source for emerging tropical infectious diseases.
Collapse
|
14
|
O'Brien CR, Malik R, Globan M, Reppas G, McCowan C, Fyfe JA. Feline leprosy due to Candidatus 'Mycobacterium tarwinense':Further clinical and molecular characterisation of 15 previously reported cases and an additional 27 cases. J Feline Med Surg 2017; 19:498-512. [PMID: 28438086 DOI: 10.1177/1098612x17706467] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES This paper, the first in a series of three on 'feline leprosy', provides a detailed description of disease referable to Candidatus 'Mycobacterium tarwinense', the most common cause of feline leprosy in Victoria, Australia. METHODS Cases were sourced retrospectively and prospectively for this observational study, describing clinical, geographical and molecular microbiological data for cats definitively diagnosed with Candidatus 'M tarwinense' infection. RESULTS A total of 145 cases of feline leprosy were scrutinised; 114 'new' cases were sourced from the Victorian Infectious Diseases Reference Laboratory records, veterinary pathology laboratories or veterinarians, and 31 cases were derived from six published studies. Forty-two cats were definitively diagnosed with Candidatus 'M tarwinense' infection. Typically, cats were between 3 and 11 years of age, with no gender predilection, and were generally systemically well. All had outdoor access. Most cats underwent surgical resection of lesions with adjunctive medical therapy, often utilising a combination of oral clarithromycin and rifampicin for at least 3 months. Prognosis for recovery was generally good. Resolution of lesions was not observed in the absence of treatment, but a number of untreated cats continued to enjoy an acceptable quality of life despite persistence of the disease, which extended locally but did not appear to disseminate to internal organs. Preliminary results of draft genome sequencing confirmed that the species is a member of the Mycobacterium simiae complex. CONCLUSIONS AND RELEVANCE Candidatus 'M tarwinense', a fastidious member of the M simiae complex, is capable of causing feline leprosy with a tendency to produce lesions on the head, particularly involving the eyes and periocular skin. The disease has an indolent clinical course and generally responds favourably to therapy despite lesions often containing large numbers of organisms. Detailed genomic analysis may yield clues as to the environmental niche and culture requirement of this elusive organism. Prospective treatment trials and/or drug susceptibility testing in specialised systems would further inform treatment recommendations.
Collapse
Affiliation(s)
- Carolyn R O'Brien
- 1 Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC 3030, Australia
| | - Richard Malik
- 2 Centre for Veterinary Education, The University of Sydney, NSW 2006, Australia
| | - Maria Globan
- 3 Victorian Infectious Diseases Reference Laboratory, Melbourne, VIC 3000, Australia
| | - George Reppas
- 4 Vetnostics, 60 Waterloo Road, North Ryde, NSW 2113, Australia
| | - Christina McCowan
- 1 Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC 3030, Australia.,5 Department of Environment and Primary Industries, Bundoora, VIC 3083, Australia
| | - Janet A Fyfe
- 3 Victorian Infectious Diseases Reference Laboratory, Melbourne, VIC 3000, Australia
| |
Collapse
|
15
|
Thirunavukkarasu S, Plain KM, de Silva K, Marais BJ, Whittington RJ. Applying the One Health Concept to Mycobacterial Research - Overcoming Parochialism. Zoonoses Public Health 2017; 64:401-422. [PMID: 28084673 DOI: 10.1111/zph.12334] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Indexed: 12/27/2022]
Abstract
Mycobacterial infections remain a public health problem. Historically important, globally ubiquitous and with a wide host range, we are still struggling to control mycobacterial infections in humans and animals. While previous reviews have focused on individual mycobacterial infections in either humans or animals, a comprehensive review of the zoonotic aspect of mycobacteria in the context of the One Health initiative is lacking. With the purpose of providing a concise and comprehensive resource, we have collated literature to address the zoonotic potential of different mycobacterial species and elaborate on the necessity for an inter-sectorial approach to attain a new vision to combat mycobacterial infections.
Collapse
Affiliation(s)
- S Thirunavukkarasu
- Faculty of Veterinary Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia.,Boise Veterans Affairs Medical Center, Boise, ID, USA
| | - K M Plain
- Faculty of Veterinary Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - K de Silva
- Faculty of Veterinary Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - B J Marais
- Marie Bashir Institute for Infectious Diseases and Biosecurity and the Centre for Research Excellence in Emerging Infections, University of Sydney, Sydney, NSW, Australia
| | - R J Whittington
- Faculty of Veterinary Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
16
|
Yotsu RR, Murase C, Sugawara M, Suzuki K, Nakanaga K, Ishii N, Asiedu K. Revisiting Buruli ulcer. J Dermatol 2015; 42:1033-41. [PMID: 26332541 DOI: 10.1111/1346-8138.13049] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 06/23/2015] [Indexed: 11/27/2022]
Abstract
Buruli ulcer (BU), or Mycobacterium ulcerans infection, is a new emerging infectious disease which has been reported in over 33 countries worldwide. It has been noted not only in tropical areas, such as West Africa where it is most endemic, but also in moderate non-tropical climate areas, including Australia and Japan. Clinical presentation starts with a papule, nodule, plaque or edematous form which eventually leads to extensive skin ulceration. It can affect all age groups, but especially children aged between 5 and 15 years in West Africa. Multiple-antibiotic treatment has proven effective, and with surgical intervention at times of severity, it is curable. However, if diagnosis and treatment is delayed, those affected may be left with life-long disabilities. The disease is not yet fully understood, including its route of transmission and pathogenesis. However, due to recent research, several important features of the disease are now being elucidated. Notably, there may be undiagnosed cases in other parts of the world where BU has not yet been reported. Japan exemplifies the finding that awareness among dermatologists plays a key role in BU case detection. So, what about in other countries where a case of BU has never been diagnosed and there is no awareness of the disease among the population or, more importantly, among health professionals? This article will revisit BU, reviewing clinical features as well as the most recent epidemiological and scientific findings of the disease, to raise awareness of BU among dermatologists worldwide.
Collapse
Affiliation(s)
- Rie R Yotsu
- Department of Dermatology, National Suruga Sanatorium, Shizuoka, Japan.,Department of Dermatology, National Center for Global Health and Medicine, Tokyo, Japan
| | - Chiaki Murase
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | | | - Koichi Suzuki
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan.,Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kazue Nakanaga
- Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Norihisa Ishii
- Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kingsley Asiedu
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| |
Collapse
|
17
|
Mycobacterium ulcerans Disease (Buruli Ulcer): Potential Reservoirs and Vectors. CURRENT CLINICAL MICROBIOLOGY REPORTS 2015. [DOI: 10.1007/s40588-015-0013-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
18
|
Abstract
PURPOSE OF REVIEW Skin and soft tissues infections (SSTIs) caused by nontuberculous mycobacteria (NTM) are underrecognized and difficult to treat. Controversies exist for optimal medical management and the role of surgery. Defining the epidemiology in the environment, in animals and in healthcare aids disease prevention. This review focuses on recent advances in epidemiology, risk factors, diagnostics and therapy. RECENT FINDINGS The increasing consumer appetite for cosmetic and body-modifying procedures (e.g. tattooing, mesotherapy, liposuction) has been associated with rises in sporadic cases and outbreaks of NTM SSTIs. In mainstream healthcare, recent epidemiological studies have helped to quantify the increased risk of NTM infection related to anti-tumour necrosis factor-α monoclonal antibody therapy. Cervicofacial lymphadenitis in children poses management dilemmas, but recent studies and resultant algorithms have simplified decision-making. Molecular studies have led to a better understanding of the epidemiology, therapy and course of Mycobacterium ulcerans infection (Buruli ulcer) that remains prevalent in many areas including sub-Saharan Africa and southeastern Australia. Apart from molecular methods, the widespread adoption of matrix-assisted laser desorption ionization-time of flight mass spectrometry by routine laboratories has potential to simplify and expedite the laboratory identification of NTMs. SUMMARY An improved understanding of the epidemiology of NTM SSTIs indicates a need to apply effective infection control and ensure regulation of cosmetic and related procedures associated with nonsterile fluids. Broader access to newer diagnostic methods will continue to improve recognition of NTM disease. Along with a paucity of therapeutic agents, there is need for more reliable methods to assess susceptibility and selection of effective combination therapy.
Collapse
|
19
|
Bolz M, Ruggli N, Ruf MT, Ricklin ME, Zimmer G, Pluschke G. Experimental infection of the pig with Mycobacterium ulcerans: a novel model for studying the pathogenesis of Buruli ulcer disease. PLoS Negl Trop Dis 2014; 8:e2968. [PMID: 25010421 PMCID: PMC4091941 DOI: 10.1371/journal.pntd.0002968] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 05/31/2014] [Indexed: 12/04/2022] Open
Abstract
Background Buruli ulcer (BU) is a slowly progressing, necrotising disease of the skin caused by infection with Mycobacterium ulcerans. Non-ulcerative manifestations are nodules, plaques and oedema, which may progress to ulceration of large parts of the skin. Histopathologically, BU is characterized by coagulative necrosis, fat cell ghosts, epidermal hyperplasia, clusters of extracellular acid fast bacilli (AFB) in the subcutaneous tissue and lack of major inflammatory infiltration. The mode of transmission of BU is not clear and there is only limited information on the early pathogenesis of the disease available. Methodology/Principal Findings For evaluating the potential of the pig as experimental infection model for BU, we infected pigs subcutaneously with different doses of M. ulcerans. The infected skin sites were excised 2.5 or 6.5 weeks after infection and processed for histopathological analysis. With doses of 2×107 and 2×106 colony forming units (CFU) we observed the development of nodular lesions that subsequently progressed to ulcerative or plaque-like lesions. At lower inoculation doses signs of infection found after 2.5 weeks had spontaneously resolved at 6.5 weeks. The observed macroscopic and histopathological changes closely resembled those found in M. ulcerans disease in humans. Conclusion/Significance Our results demonstrate that the pig can be infected with M. ulcerans. Productive infection leads to the development of lesions that closely resemble human BU lesions. The pig infection model therefore has great potential for studying the early pathogenesis of BU and for the development of new therapeutic and prophylactic interventions. Buruli ulcer caused by Mycobacterium ulcerans infection is a necrotizing disease of the skin and the underlying subcutaneous tissue. Since the skin of pigs (Sus scrofa) has striking structural and physiological similarities with human skin, we investigated whether it is possible to develop an experimental M. ulcerans infection model by subcutaneous injection of the mycobacteria into pig skin. Injection of 2×106 or 2×107 colony forming units of M. ulcerans led to the development of lesions that were both macroscopically and microscopically very similar to human Buruli ulcer lesions. In particular for the characterization of the pathogenesis of Buruli ulcer and of immune defence mechanisms against M. ulcerans, the pig model appears to be superior to the mouse foot pad model commonly used for the evaluation of the efficacy of chemotherapeutic regimens.
Collapse
Affiliation(s)
- Miriam Bolz
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nicolas Ruggli
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland
| | - Marie-Thérèse Ruf
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Meret E. Ricklin
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland
| | - Gert Zimmer
- Institute of Virology and Immunology (IVI), Mittelhäusern, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| |
Collapse
|
20
|
O'Brien CR, Handasyde KA, Hibble J, Lavender CJ, Legione AR, McCowan C, Globan M, Mitchell AT, McCracken HE, Johnson PDR, Fyfe JAM. Clinical, microbiological and pathological findings of Mycobacterium ulcerans infection in three Australian Possum species. PLoS Negl Trop Dis 2014; 8:e2666. [PMID: 24498451 PMCID: PMC3907337 DOI: 10.1371/journal.pntd.0002666] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 12/12/2013] [Indexed: 11/19/2022] Open
Abstract
Background Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans, with endemicity predominantly in sub-Saharan Africa and south-eastern Australia. The mode of transmission and the environmental reservoir(s) of the bacterium and remain elusive. Real-time PCR investigations have detected M. ulcerans DNA in a variety of Australian environmental samples, including the faeces of native possums with and without clinical evidence of infection. This report seeks to expand on previously published findings by the authors' investigative group with regards to clinical and subclinical disease in selected wild possum species in BU-endemic areas of Victoria, Australia. Methodology/Principal Findings Twenty-seven clinical cases of M. ulcerans infection in free-ranging possums from southeastern Australia were identified retrospectively and prospectively between 1998–2011. Common ringtail possums (Pseudocheirus peregrinus), a common brushtail possum (Trichosurus vulpecula) and a mountain brushtail possum (Trichosurus cunninghami) were included in the clinically affected cohort. Most clinically apparent cases were adults with solitary or multiple ulcerative cutaneous lesions, generally confined to the face, limbs and/or tail. The disease was minor and self-limiting in the case of both Trichosurus spp. possums. In contrast, many of the common ringtail possums had cutaneous disease involving disparate anatomical sites, and in four cases there was evidence of systemic disease at post mortem examination. Where tested using real-time PCR targeted at IS2404, animals typically had significant levels of M. ulcerans DNA throughout the gut and/or faeces. A further 12 possums without cutaneous lesions were found to have PCR-positive gut contents and/or faeces (subclinical cases), and in one of these the organism was cultured from liver tissue. Comparisons were made between clinically and subclinically affected possums, and 61 PCR-negative, non-affected individuals, with regards to disease category and the categorical variables of species (common ringtail possums v others) and sex. Animals with clinical lesions were significantly more likely to be male common ringtail possums. Conclusions/Significance There is significant disease burden in common ringtail possums (especially males) in some areas of Victoria endemic for M. ulcerans disease. The natural history of the disease generally remains unknown, however it appears that some mildly affected common brushtail and mountain brushtail possums can spontaneously overcome the infection, whereas some severely affected animals, especially common ringtail possums, may become systemically, and potentially fatally affected. Subclinical gut carriage of M. ulcerans DNA in possums is quite common and in some common brushtail and mountain brushtail possums this is transient. Further work is required to determine whether M. ulcerans infection poses a potential threat to possum populations, and whether these animals are acting as environmental reservoirs in certain geographical areas. Mycobacterium ulcerans causes skin disease predominantly in sub-Saharan Africa and southeastern Australia. The mode of transmission and the environmental reservoir(s) of the bacterium are unknown. Investigations have detected M. ulcerans DNA in a variety of Australian environmental samples, including the faeces of native possums. This report expands on these studies by detailing the clinical, pathological and microbiological findings in affected wild possum species in endemic areas. Twenty-seven clinically and 12 subclinically affected individuals were identified. Most clinical cases were adults with skin ulcers of the face, limbs and/or tail. The disease was mild and self-limiting in both Trichosurus spp. possums. In contrast, many of the common ringtail possums had multiple skin ulcers and in some there was evidence of internal disease. There were also significant levels of M. ulcerans DNA throughout the gut. Comparisons were made with regards to disease category, species and sex; with clinical cases more likely to be male common ringtail possums. Asymptomatic gut carriage of M. ulcerans DNA is quite common and may be transient in some individuals. Further work is needed to determine whether M. ulcerans infection poses a potential threat to possum populations, and whether these animals are acting as reservoirs in some areas.
Collapse
Affiliation(s)
- Carolyn R. O'Brien
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
- * E-mail: , co'
| | | | - Jennifer Hibble
- Newhaven Veterinary Clinic, Phillip Island, Victoria, Australia
| | - Caroline J. Lavender
- WHO Collaborating Centre for Mycobacterium ulcerans (Western Pacific Region), Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia
| | - Alistair R. Legione
- Department of Zoology, The University of Melbourne, Parkville, Victoria, Australia
| | - Christina McCowan
- Department of Environment and Primary Industries, Veterinary Diagnostic Services, Bundoora, Victoria, Australia
- The University of Melbourne Veterinary Hospital, Werribee, Victoria, Australia
| | - Maria Globan
- WHO Collaborating Centre for Mycobacterium ulcerans (Western Pacific Region), Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia
| | - Anthony T. Mitchell
- Department of Environment and Primary Industries, Orbost, Victoria, Australia
| | | | - Paul D. R. Johnson
- WHO Collaborating Centre for Mycobacterium ulcerans (Western Pacific Region), Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia
- Department of Infectious Diseases, Austin Health, Heidelberg, Victoria, Australia
| | - Janet A. M. Fyfe
- WHO Collaborating Centre for Mycobacterium ulcerans (Western Pacific Region), Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia
| |
Collapse
|
21
|
Carson C, Lavender CJ, Handasyde KA, O'Brien CR, Hewitt N, Johnson PDR, Fyfe JAM. Potential wildlife sentinels for monitoring the endemic spread of human buruli ulcer in South-East australia. PLoS Negl Trop Dis 2014; 8:e2668. [PMID: 24498452 PMCID: PMC3907424 DOI: 10.1371/journal.pntd.0002668] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 12/12/2013] [Indexed: 11/18/2022] Open
Abstract
The last 20 years has seen a significant series of outbreaks of Buruli/Bairnsdale Ulcer (BU), caused by Mycobacterium ulcerans, in temperate south-eastern Australia (state of Victoria). Here, the prevailing view of M. ulcerans as an aquatic pathogen has been questioned by recent research identifying native wildlife as potential terrestrial reservoirs of infection; specifically, tree-dwelling common ringtail and brushtail possums. In that previous work, sampling of environmental possum faeces detected a high prevalence of M. ulcerans DNA in established endemic areas for human BU on the Bellarine Peninsula, compared with non-endemic areas. Here, we report research from an emergent BU focus recently identified on the Mornington Peninsula, confirming associations between human BU and the presence of the aetiological agent in possum faeces, detected by real-time PCR targeting M. ulcerans IS2404, IS2606 and KR. Mycobacterium ulcerans DNA was detected in 20/216 (9.3%) ground collected ringtail possum faecal samples and 4/6 (66.6%) brushtail possum faecal samples. The distribution of the PCR positive possum faecal samples and human BU cases was highly focal: there was a significant non-random cluster of 16 M. ulcerans positive possum faecal sample points detected by spatial scan statistics (P<0.0001) within a circle of radius 0.42 km, within which were located the addresses of 6/12 human cases reported from the area to date; moreover, the highest sample PCR signal strength (equivalent to ≥10(6) organisms per gram of faeces) was found in a sample point located within this cluster radius. Corresponding faecal samples collected from closely adjacent BU-free areas were predominantly negative. Possums may be useful sentinels to predict endemic spread of human BU in Victoria, for public health planning. Further research is needed to establish whether spatial associations represent evidence of direct or indirect transmission between possums and humans, and the mechanism by which this may occur.
Collapse
Affiliation(s)
- Connor Carson
- Victorian Infectious Diseases Reference Laboratory (VIDRL), North Melbourne, Victoria, Australia
| | - Caroline J. Lavender
- Victorian Infectious Diseases Reference Laboratory (VIDRL), North Melbourne, Victoria, Australia
| | | | - Carolyn R. O'Brien
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Nick Hewitt
- Communicable Disease Prevention and Control, Department of Health, Melbourne, Victoria, Australia
- Infectious Diseases Department, Austin Health, Heidelberg, Victoria, Australia
| | - Paul D. R. Johnson
- Infectious Diseases Department, Austin Health, Heidelberg, Victoria, Australia
| | - Janet A. M. Fyfe
- Victorian Infectious Diseases Reference Laboratory (VIDRL), North Melbourne, Victoria, Australia
| |
Collapse
|
22
|
Malik R, Smits B, Reppas G, Laprie C, O'Brien C, Fyfe J. Ulcerated and nonulcerated nontuberculous cutaneous mycobacterial granulomas in cats and dogs. Vet Dermatol 2013; 24:146-53.e32-3. [PMID: 23331691 DOI: 10.1111/j.1365-3164.2012.01104.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Mycobacterial granulomas of the skin and subcutis can be caused by one of a number of pathogens. This review concentrates on noncultivable species that cause diseases characterized by focal granuloma(s), namely leproid granuloma (in dogs) and feline leprosy (in cats). Clinically indistinguishable lesions can be caused by tuberculous organisms (Mycobacterium bovis and Mycobacterium microti) and members of the Mycobacterium avium complex. Rapidly growing mycobacterial species that cause infection of the subcutaneous panniculus associated with draining tracts are not discussed. Disease caused by Mycobacterium ulcerans is an important emerging differential diagnosis for ulcerated cutaneous nodules in certain localized regions. CLINICAL LESIONS: Lesions comprise one or multiple nodules in the skin/subcutis. These are generally firm and well circumscribed, and typically become denuded of hair. They may or may not ulcerate, depending on the virulence of the causal organisms and the immune response of the host. DIAGNOSIS The most inexpensive, noninvasive means of diagnosis is by submission of methanol-fixed, Romanowsky-stained smears to a Mycobacterium Reference Laboratory after detecting negatively stained or acid-fast bacilli on cytological smears. Scrapings of material from slides usually provide sufficient mycobacterial DNA to enable identification of the causal organism using sequence analysis of amplicons after PCR using specific mycobacterial primers. THERAPY Therapy relies upon a combination of marginal resection of easily accessible lesions and treatment using two or three drugs effective against slowly growing mycobacteria, choosing amongst rifampicin, clarithromycin, clofazimine and pradofloxacin/moxifloxacin.
Collapse
Affiliation(s)
- Richard Malik
- Centre for Veterinary Education, Conference Centre B22, The University of Sydney, Sydney, NSW, Australia.
| | | | | | | | | | | |
Collapse
|
23
|
O'Brien C, Kuseff G, McMillan E, McCowan C, Lavender C, Globan M, Jerrett I, Oppedisano F, Johnson P, Fyfe J. Mycobacterium ulceransinfection in two alpacas. Aust Vet J 2013; 91:296-300. [DOI: 10.1111/avj.12071] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2012] [Indexed: 11/29/2022]
Affiliation(s)
- C O'Brien
- Faculty of Veterinary Science; University of Melbourne; Parkville; Victoria; 3052; Australia
| | - G Kuseff
- Main Street Veterinary Clinic; Bairnsdale; VIC; Australia
| | - E McMillan
- Bellarine Animal Hospital; Newcomb; VIC; Australia
| | - C McCowan
- Department of Primary Industries; Attwood; VIC; Australia
| | - C Lavender
- Mycobacterium Reference Laboratory; Victoria Infectious Diseases Reference Laboratory; North Melbourne; VIC; Australia
| | - M Globan
- Mycobacterium Reference Laboratory; Victoria Infectious Diseases Reference Laboratory; North Melbourne; VIC; Australia
| | - I Jerrett
- Department of Primary Industries; Attwood; VIC; Australia
| | - F Oppedisano
- Microbiology Research Laboratory; The Royal Children's Hospital; Parkville; VIC; Australia
| | | | - J Fyfe
- Mycobacterium Reference Laboratory; Victoria Infectious Diseases Reference Laboratory; North Melbourne; VIC; Australia
| |
Collapse
|
24
|
Environmental distribution and seasonal prevalence of Mycobacterium ulcerans in Southern Louisiana. Appl Environ Microbiol 2013; 79:2648-56. [PMID: 23396345 DOI: 10.1128/aem.03543-12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mycobacterium ulcerans is an emerging environmental pathogen that causes debilitating, ulcerative disease in humans and other vertebrates. The majority of human cases occur in tropical and temperate regions of Africa and Australia, and outbreaks of piscine mycobacteriosis caused by M. ulcerans have been reported in disparate geographic locations spanning the globe. While exposure to a natural body of water is the most common risk factor for human infection, the environmental distribution of M. ulcerans in aquatic habitats has not been extensively studied. Although no human cases have been reported in the United States, a strain of M. ulcerans has been identified as the cause of a piscine mycobacteriosis in Striped bass (Morone saxatilis) within the Chesapeake Bay. Infected fish exhibit bright red ventral and lateral dermal lesions. We observed a possible outbreak causing similar lesions on red drum (Sciaenops ocellatus) in wetlands of southern Louisiana and detected M. ulcerans-specific genetic markers in lesion samples from these fish. Based on these findings, we studied the geographic and seasonal prevalence of these markers across southern Louisiana. M. ulcerans was detected in each of the nine areas sampled across the state. M. ulcerans prevalence was significantly lower in the fall samples, and the low prevalence coincided with decreased nutrient levels and an increase in water temperature. To our knowledge, this is the first study of M. ulcerans biomarkers in the southern United States.
Collapse
|
25
|
|
26
|
Mosi L, Mutoji NK, Basile FA, Donnell R, Jackson KL, Spangenberg T, Kishi Y, Ennis DG, Small PLC. Mycobacterium ulcerans causes minimal pathogenesis and colonization in medaka (Oryzias latipes): an experimental fish model of disease transmission. Microbes Infect 2012; 14:719-29. [PMID: 22465732 PMCID: PMC3389220 DOI: 10.1016/j.micinf.2012.02.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 02/23/2012] [Accepted: 02/24/2012] [Indexed: 10/28/2022]
Abstract
Mycobacterium ulcerans causes Buruli ulcer in humans, a progressive ulcerative epidermal lesion due to the mycolactone toxin produced by the bacterium. Molecular analysis of M. ulcerans reveals it is closely related to Mycobacterium marinum, a pathogen of both fish and man. Molecular evidence from diagnostic PCR assays for the insertion sequence IS2404 suggests an association of M. ulcerans with fish. However, fish infections by M. ulcerans have not been well documented and IS2404 has been found in other mycobacteria. We have thus, employed two experimental approaches to test for M. ulcerans in fish. We show here for the first time that M. ulcerans with or without the toxin does not mount acute or chronic infections in Japanese Medaka "Oryzias latipes" even at high doses. Moreover, M. ulcerans-infected medaka do not exhibit any visible signs of infection nor disease and the bacteria do not appear to replicate over time. In contrast, similar high doses of the wild-type M. marinum or a mycolactone-producing M. marinum "DL" strain are able to mount an acute disease with mortality in medaka. Although these results would suggest that M. ulcerans does not mount infections in fish we have evidence that CLC macrophages from goldfish are susceptible to mycolactones.
Collapse
Affiliation(s)
- Lydia Mosi
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
O'Brien CR, McMillan E, Harris O, O'Brien DP, Lavender CJ, Globan M, Legione AR, Fyfe JA. Localised Mycobacterium ulcerans infection in four dogs. Aust Vet J 2011; 89:506-10. [DOI: 10.1111/j.1751-0813.2011.00850.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
28
|
Fyfe JAM, Lavender CJ, Handasyde KA, Legione AR, O'Brien CR, Stinear TP, Pidot SJ, Seemann T, Benbow ME, Wallace JR, McCowan C, Johnson PDR. A major role for mammals in the ecology of Mycobacterium ulcerans. PLoS Negl Trop Dis 2010; 4:e791. [PMID: 20706592 PMCID: PMC2919402 DOI: 10.1371/journal.pntd.0000791] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Accepted: 07/12/2010] [Indexed: 12/13/2022] Open
Abstract
Background Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), a destructive skin disease found predominantly in sub-Saharan Africa and south-eastern Australia. The precise mode(s) of transmission and environmental reservoir(s) remain unknown, but several studies have explored the role of aquatic invertebrate species. The purpose of this study was to investigate the environmental distribution of M. ulcerans in south-eastern Australia. Methodology/Principal Findings A range of environmental samples was collected from Point Lonsdale (a small coastal town southwest of Melbourne, Australia, endemic for BU) and from areas with fewer or no reported incident cases of BU. Mycobacterium ulcerans DNA was detected at low levels by real-time PCR in soil, sediment, water residue, aquatic plant biofilm and terrestrial vegetation collected in Point Lonsdale. Higher levels of M. ulcerans DNA were detected in the faeces of common ringtail (Pseudocheirus peregrinus) and common brushtail (Trichosurus vulpecula) possums. Systematic testing of possum faeces revealed that M. ulcerans DNA could be detected in 41% of faecal samples collected in Point Lonsdale compared with less than 1% of faecal samples collected from non-endemic areas (p<0.0001). Capture and clinical examination of live possums in Point Lonsdale validated the accuracy of the predictive value of the faecal surveys by revealing that 38% of ringtail possums and 24% of brushtail possums had laboratory-confirmed M. ulcerans skin lesions and/or M. ulcerans PCR positive faeces. Whole genome sequencing revealed an extremely close genetic relationship between human and possum M. ulcerans isolates. Conclusions/Significance The prevailing wisdom is that M. ulcerans is an aquatic pathogen and that BU is acquired by contact with certain aquatic environments (swamps, slow-flowing water). Now, after 70 years of research, we propose a transmission model for BU in which terrestrial mammals are implicated as reservoirs for M. ulcerans. Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), a destructive skin disease found predominantly in sub-Saharan Africa and south-eastern Australia. The mode of transmission and environmental reservoir remain unknown, but several studies have explored the role of aquatic insects, such as water bugs, and biting insects, such as mosquitoes. In the present study we investigated possible environmental source(s) of M. ulcerans in Victoria, Australia. Our results revealed that although M. ulcerans DNA could be detected at low levels in a variety of environmental samples, the highest concentrations of M. ulcerans DNA were found in the faeces of two species of possums, common ringtails and common brushtails. Possums are small arboreal marsupial mammals, native to Australia, and these particular species occur in both urban and rural areas. Examination and sampling of live captured possums in an area endemic for BU revealed that 38% of ringtail possums and 24% of brushtail possums, respectively, had laboratory-confirmed M. ulcerans lesions and/or M. ulcerans PCR-positive faeces. The finding that large numbers of possums in a BU-endemic area are infected with M. ulcerans raises the possibility that mammals are an environmental reservoir for M. ulcerans.
Collapse
Affiliation(s)
- Janet A M Fyfe
- Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Jackson AE. In this issue - March 2010. Aust Vet J 2010; 88:61-3. [PMID: 20402684 DOI: 10.1111/j.1751-0813.2010.00491.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|