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Herron ICT, Laws TR, Nelson M. Marmosets as models of infectious diseases. Front Cell Infect Microbiol 2024; 14:1340017. [PMID: 38465237 PMCID: PMC10921895 DOI: 10.3389/fcimb.2024.1340017] [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: 11/17/2023] [Accepted: 01/29/2024] [Indexed: 03/12/2024] Open
Abstract
Animal models of infectious disease often serve a crucial purpose in obtaining licensure of therapeutics and medical countermeasures, particularly in situations where human trials are not feasible, i.e., for those diseases that occur infrequently in the human population. The common marmoset (Callithrix jacchus), a Neotropical new-world (platyrrhines) non-human primate, has gained increasing attention as an animal model for a number of diseases given its small size, availability and evolutionary proximity to humans. This review aims to (i) discuss the pros and cons of the common marmoset as an animal model by providing a brief snapshot of how marmosets are currently utilized in biomedical research, (ii) summarize and evaluate relevant aspects of the marmoset immune system to the study of infectious diseases, (iii) provide a historical backdrop, outlining the significance of infectious diseases and the importance of developing reliable animal models to test novel therapeutics, and (iv) provide a summary of infectious diseases for which a marmoset model exists, followed by an in-depth discussion of the marmoset models of two studied bacterial infectious diseases (tularemia and melioidosis) and one viral infectious disease (viral hepatitis C).
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Affiliation(s)
- Ian C. T. Herron
- CBR Division, Defence Science and Technology Laboratory (Dstl), Salisbury, United Kingdom
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2
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Savelkoel J, Tiemensma M, Birnie E, Wiersinga WJ, Currie BJ, Roelofs JJTH. A Graphical Overview of the Histopathology of Human Melioidosis: A Case Series. Open Forum Infect Dis 2023; 10:ofad367. [PMID: 37547853 PMCID: PMC10400137 DOI: 10.1093/ofid/ofad367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/11/2023] [Indexed: 08/08/2023] Open
Abstract
Background Melioidosis, caused by the Gram-negative bacterium Burkholderia pseudomallei, has a major global health impact and a wide range of different disease manifestations. Histopathological descriptions of melioidosis remain limited. Granulomatous inflammation with multinucleated giant cells are considered classic features. We aim to present a graphical overview of histopathological manifestations of melioidosis, serving as an aid in diagnosing this disease. Methods We performed a retrospective international multicenter laboratory-based analysis of formalin-fixed paraffin-embedded (FFPE) tissue from culture-confirmed melioidosis autopsy and biopsy cases. Available FFPE tissue was stained with hematoxylin and eosin and immunostainings including a monoclonal antibody targeting the capsular polysaccharide (CPS) of B pseudomallei. Tissue with site-specific cultures and/or positive CPS staining were included in the graphical histopathological overview. Results We identified tissue of 8 autopsy and 5 biopsy cases. Pneumonia and soft tissue abscesses were the leading foci of disease displaying mainly necrosis and suppuration. Infrequent disease manifestations included involvement of bone marrow and adrenal glands in an autopsy case and biopsied mediastinal tissue, the latter being the only case in which we identified multinucleated giant cells. Using the CPS staining, we demonstrated granulomata as part of rare gastric tissue involvement. Conclusions We found fatal melioidosis to be a necrotizing and suppurative inflammation, usually without multinucleated giant cell formation. Gastric and mediastinal involvement points to ingestion and inhalation as possible routes of infection. The CPS staining proved beneficial as an aid to establish a histopathological diagnosis. Our graphical overview can be used by infectious diseases specialists, microbiologists, and pathologists.
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Affiliation(s)
- Jelmer Savelkoel
- Center for Experimental and Molecular Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
| | - Marianne Tiemensma
- Territory Pathology, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - Emma Birnie
- Center for Experimental and Molecular Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
| | - W Joost Wiersinga
- Center for Experimental and Molecular Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
- Division of Infectious Diseases, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
| | - Bart J Currie
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
- Infectious Diseases Department, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - Joris J T H Roelofs
- Department of Pathology, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
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Abstract
The soil saprophyte, Burkholderia pseudomallei, is the causative agent of melioidosis, a disease endemic in South East Asia and northern Australia. Exposure to B. pseudomallei by either inhalation or inoculation can lead to severe disease. B. pseudomallei rapidly shifts from an environmental organism to an aggressive intracellular pathogen capable of rapidly spreading around the body. The expression of multiple virulence factors at every stage of intracellular infection allows for rapid progression of infection. Following invasion or phagocytosis, B. pseudomallei resists host-cell killing mechanisms in the phagosome, followed by escape using the type III secretion system. Several secreted virulence factors manipulate the host cell, while bacterial cells undergo a shift in energy metabolism allowing for overwhelming intracellular replication. Polymerisation of host cell actin into “actin tails” propels B. pseudomallei to the membranes of host cells where the type VI secretion system fuses host cells into multinucleated giant cells (MNGCs) to facilitate cell-to-cell dissemination. This review describes the various mechanisms used by B. pseudomallei to survive within cells.
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Affiliation(s)
- Nicole M Bzdyl
- The Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Clare L Moran
- The Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Justine Bendo
- The Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Mitali Sarkar-Tyson
- The Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, 6009, Australia
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Venkateswaran KS, Parameswaran N, Sarwar J, Plummer A, Santos A, Pillai CA, Bowen S, Granville M, Selvan S, Babu P, Thirunavukkarasu N, Venkateswaran N, Sharma S, Morse SA, Anderson K, Hodge DR, Pillai SP. Rapid Presumptive Identification of Burkholderia mallei and Burkholderia pseudomallei Clinical Isolates Using a Highly Specific Lateral Flow Assay. Health Secur 2022; 20:164-171. [PMID: 35467946 DOI: 10.1089/hs.2021.0172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We conducted a comprehensive, multiphase laboratory evaluation of the InBios Active Melioidosis Detect (AMD) rapid test, a lateral flow immunoassay designed to detect capsular polysaccharides produced by Burkholderia mallei or Burkholderia pseudomallei, used in conjunction with the Omni Array Reader for the rapid identification of culture isolates of B mallei or B pseudomallei to support clinical diagnosis for response and triage during a mass casualty event, such as a biological attack. The study was conducted at 2 sites to assess the performance of the AMD test. The sensitivity, specificity, and reproducibility of the assay was determined using 5 replicates of 35 inclusivity strains and 64 clinical background strains. A total of 520 tests were performed, which included both positive and negative controls. Results obtained visually and with the Omni Array Reader showed a sensitivity of 92.3% for B mallei and 95.6% for B pseudomallei; no cross-reactivity was observed with any of the 64 clinical background organisms. The results from this study indicate that the AMD test for the presumptive identification of B mallei and B pseudomallei isolates to support clinical diagnosis is highly robust, specific, and sensitive. This evaluation supports the use of this test as a rapid, qualitative assay for the presumptive identification of B mallei and B pseudomallei in a clinical setting.
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Affiliation(s)
- Kodumudi S Venkateswaran
- Kodumudi S. Venkateswaran, PhD, is Chief Executive Officer, Omni Array Biotechnology, Rockville, MD
| | | | - Jawad Sarwar
- Jawad Sarwar, MS, is Scientist, Omni Array Biotechnology, Rockville, MD
| | - Andrea Plummer
- Andrea Plummer Microbiologist, Tetracore, Inc., Rockville, MD
| | - Alan Santos
- Alan Santos is Microbiologist, Tetracore, Inc., Rockville, MD
| | - Christine A Pillai
- Christine A. Pillai is a Oak Ridge Institute for Science and Education Fellow Research Scientist, Molecular Methods Development Branch, Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD
| | - Samantha Bowen
- Samantha Bowen, MS, is Project Manager, Science and Technology Directorate, US Department of Homeland Security, Washington, DC
| | - Maria Granville
- Maria Granville, MS, is Project Manager, Science and Technology Directorate, US Department of Homeland Security, Washington, DC
| | - Senthamil Selvan
- Senthamil Selvan, PhD, is Vice President, Omni Array Biotechnology, Rockville, MD
| | - Prasanti Babu
- Prasanti Babu, MS, is a Research Associate, Omni Array Biotechnology, Rockville, MD
| | - Nagarajan Thirunavukkarasu
- Nagarajan Thirunavukkarasu, PhD, is a Microbiologist, Molecular Methods Development Branch, Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD
| | | | - Shashi Sharma
- Shashi Sharma, PhD, is Principal Investigator, Molecular Methods Development Branch, Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD
| | - Stephen A Morse
- Stephen A. Morse, MSPH, PhD, is Senior Scientist, IHRC, Inc., Atlanta, GA
| | - Kevin Anderson
- Kevin Anderson, PhD, is Program Manager, Science and Technology Directorate, US Department of Homeland Security, Washington, DC
| | - David R Hodge
- David R. Hodge, PhD, is Program Manager, Science and Technology Directorate, US Department of Homeland Security, Washington, DC
| | - Segaran P Pillai
- Segaran P. Pillai, PhD, FAAM, SM(NRCM), SM(ASCP), is Director, Office of Laboratory Safety, Office of the Commissioner, US Food and Drug Administration, Silver Spring, MD
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Ku JWK, Marsh ST, Nai MH, Robinson KS, Teo DET, Zhong FL, Brown KA, Lim TC, Lim CT, Gan YH. Skin models for cutaneous melioidosis reveal Burkholderia infection dynamics at wound's edge with inflammasome activation, keratinocyte extrusion and epidermal detachment. Emerg Microbes Infect 2021; 10:2326-2339. [PMID: 34821529 PMCID: PMC8654412 DOI: 10.1080/22221751.2021.2011621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Melioidosis is a serious infectious disease endemic in Southeast Asia, Northern Australia and has been increasingly reported in other tropical and subtropical regions in the world. Percutaneous inoculation through cuts and wounds on the skin is one of the major modes of natural transmission. Despite cuts in skin being a major route of entry, very little is known about how the causative bacterium Burkholderia pseudomallei initiates an infection at the skin and the disease manifestation at the skin known as cutaneous melioidosis. One key issue is the lack of suitable and relevant infection models. Employing an in vitro 2D keratinocyte cell culture, a 3D skin equivalent fibroblast-keratinocyte co-culture and ex vivo organ culture from human skin, we developed infection models utilizing surrogate model organism Burkholderia thailandensis to investigate Burkholderia-skin interactions. Collectively, these models show that the bacterial infection was largely limited at the wound’s edge. Infection impedes wound closure, triggers inflammasome activation and cellular extrusion in the keratinocytes as a potential way to control bacterial infectious load at the skin. However, extensive infection over time could result in the epidermal layer being sloughed off, potentially contributing to formation of skin lesions.
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Affiliation(s)
- Joanne Wei Kay Ku
- Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Supatra Tharinee Marsh
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | - Mui Hoon Nai
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | | | - Daniel Eng Thiam Teo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Franklin Lei Zhong
- Skin Research Institute of Singapore (SRIS), Immunos, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Katherine A Brown
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.,Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX, USA
| | - Thiam Chye Lim
- Division of Plastic, Reconstructive &Aesthetic Surgery, National University Health System, Singapore, Singapore
| | - Chwee Teck Lim
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore.,Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, Singapore
| | - Yunn-Hwen Gan
- Department of Biochemistry, National University of Singapore, Singapore, Singapore.,Infectious Diseases Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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Abstract
The causative agent of melioidosis, Burkholderia pseudomallei, a tier 1 select agent, is endemic in Southeast Asia and northern Australia, with increased incidence associated with high levels of rainfall. Increasing reports of this condition have occurred worldwide, with estimates of up to 165,000 cases and 89,000 deaths per year. The ecological niche of the organism has yet to be clearly defined, although the organism is associated with soil and water. The culture of appropriate clinical material remains the mainstay of laboratory diagnosis. Identification is best done by phenotypic methods, although mass spectrometric methods have been described. Serology has a limited diagnostic role. Direct molecular and antigen detection methods have limited availability and sensitivity. Clinical presentations of melioidosis range from acute bacteremic pneumonia to disseminated visceral abscesses and localized infections. Transmission is by direct inoculation, inhalation, or ingestion. Risk factors for melioidosis include male sex, diabetes mellitus, alcohol abuse, and immunosuppression. The organism is well adapted to intracellular survival, with numerous virulence mechanisms. Immunity likely requires innate and adaptive responses. The principles of management of this condition are drainage and debridement of infected material and appropriate antimicrobial therapy. Global mortality rates vary between 9% and 70%. Research into vaccine development is ongoing.
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Affiliation(s)
- I Gassiep
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - M Armstrong
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
| | - R Norton
- Pathology Queensland, Townsville Hospital, Townsville, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
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Lee SH, Lu YP, Shih WL, Chang CD, Tu YC, Lai IH. Development of an immunoassay using recombinant outer membrane protein A and flagellin for diagnosis of goats with melioidosis. J Vet Med Sci 2020; 82:325-332. [PMID: 31996495 PMCID: PMC7118472 DOI: 10.1292/jvms.19-0072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Among domestic animals, melioidosis is one of the most common diseases reported in goat, sheep, and swine. To evaluate the specific antibodies in goats with melioidosis, we developed a serology test using recombinant outer membrane protein A (OmpA) and flagellin (FliC) of Burkholderia pseudomallei as antigens. DNA corresponding to each antigen was cloned into a pET32a vector and expressed in Escherichia coli. Essentially, the recombinant OmpA and FliC were expressed in a soluble form that could be isolated with 95% homogeneity. Both recombinants could be recognized by rabbit antibodies prepared against heat-inactivated B. pseudomallei (1:1,000) on a Western blot. Subsequently, we demonstrated that both recombinants could capture the antibodies present in goat with naturally occurring melioidosis (optimized titer 1:40) while not cross-reacting with the serum samples of goats naturally infected by Corynebacterium pseudotuberculosis or Staphylococcus aureus. Finally, an enzyme-linked immunosorbent assay (ELISA) using 20 goat serum samples without melioidosis and 10 goat serum samples with melioidosis demonstrated that the infected group has significantly higher antibody titer levels than the normal group (P<0.001) when using either OmpA or FliC as an antigen. However, the sensitivity (100%) of the assay using OmpA was superior to that (90%) from using FliC. Serological tests that are commonly used often rely on antigens from crude cell extracts, which pose risks for laboratory-acquired infections and inconsistency in their preparation; however, use of recombinant OmpA is safe; it can potentially be used as a reagent in testing for goat melioidosis.
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Affiliation(s)
- Shu-Hwae Lee
- School of Veterinary Medicine, National Taiwan University, Taipei, 10617, Taiwan
| | - Yi-Ping Lu
- Animal Health Research Institute, Council of Agriculture, Executive Yuan, New Taipei City, 25158, Taiwan
| | - Wen-Ling Shih
- Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Ching-Dong Chang
- Department of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Yang-Chang Tu
- Animal Health Research Institute, Council of Agriculture, Executive Yuan, New Taipei City, 25158, Taiwan
| | - I-Hsiang Lai
- General Research Service Center, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
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Bearss JJ, Hunter M, Dankmeyer JL, Fritts KA, Klimko CP, Weaver CH, Shoe JL, Quirk AV, Toothman RG, Webster WM, Fetterer DP, Bozue JA, Worsham PL, Welkos SL, Amemiya K, Cote CK. Characterization of pathogenesis of and immune response to Burkholderia pseudomallei K96243 using both inhalational and intraperitoneal infection models in BALB/c and C57BL/6 mice. PLoS One 2017; 12:e0172627. [PMID: 28235018 PMCID: PMC5325312 DOI: 10.1371/journal.pone.0172627] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/07/2017] [Indexed: 01/02/2023] Open
Abstract
Burkholderia pseudomallei, the etiologic agent of melioidosis, is a Gram negative bacterium designated as a Tier 1 threat. This bacterium is known to be endemic in Southeast Asia and Northern Australia and can infect humans and animals by several routes. Inhalational melioidosis has been associated with monsoonal rains in endemic areas and is also a significant concern in the biodefense community. There are currently no effective vaccines for B. pseudomallei and antibiotic treatment can be hampered by non-specific symptomology and also the high rate of naturally occurring antibiotic resistant strains. Well-characterized animal models will be essential when selecting novel medical countermeasures for evaluation prior to human clinical trials. Here, we further characterize differences between the responses of BALB/c and C57BL/6 mice when challenged with low doses of a low-passage and well-defined stock of B. pseudomallei K96243 via either intraperitoneal or aerosol routes of exposure. Before challenge, mice were implanted with a transponder to collect body temperature readings, and daily body weights were also recorded. Mice were euthanized on select days for pathological analyses and determination of the bacterial burden in selected tissues (blood, lungs, liver, and spleen). Additionally, spleen homogenate and sera samples were analyzed to better characterize the host immune response after infection with aerosolized bacteria. These clinical, pathological, and immunological data highlighted and confirmed important similarities and differences between these murine models and exposure routes.
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Affiliation(s)
- Jeremy J. Bearss
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, MD, United States of America
| | - Melissa Hunter
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Jennifer L. Dankmeyer
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Kristen A. Fritts
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Christopher P. Klimko
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Chris H. Weaver
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Jennifer L. Shoe
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Avery V. Quirk
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Ronald G. Toothman
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Wendy M. Webster
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - David P. Fetterer
- BioStatisitics Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Joel A. Bozue
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Patricia L. Worsham
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Susan L. Welkos
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Kei Amemiya
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
| | - Christopher K. Cote
- Bacteriology Division, USAMRIID, Fort Detrick, Frederick, MD, United States of America
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Musa HI, Hassan L, Shamsuddin ZH, Panchadcharam C, Zakaria Z, Abdul Aziz S, Rachmat RFN. Case-control investigation on the risk factors of melioidosis in small ruminant farms in Peninsular Malaysia. J Appl Microbiol 2015; 119:331-41. [PMID: 25891038 DOI: 10.1111/jam.12830] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 03/30/2015] [Accepted: 04/12/2015] [Indexed: 01/13/2023]
Abstract
AIMS Epidemiology of melioidosis is poorly understood because its occurrence is influenced by complex interaction of environmental, climatic, physicochemical and host factors. We investigated the potential risk factors for the exposure to Burkholderia pseudomallei in small ruminants' farms in Peninsular Malaysia. METHODS AND RESULTS Melioidosis-positive (n = 33) and negative (n = 27) farms were selected and visited for interviews and environmental samples collection. The characteristics and putative disease risk factors were compared between the case and the control farms using Chi-square test and logistic regression analysis. The multivariable logistic regression analysis showed that the odds of melioidosis were significantly higher in farms that had bush clearing around farms (odds ratio (OR) = 6.61, 95% confidence interval (CI) = 1.12-38.84, P = 0.037), in farms with B. pseudomallei present in the soil (OR = 6.23, 95% CI = 1.03-37.68, P = 0.046), in farms that have other animal species present (OR = 7.96, 95% CI = 1.14-55.99, P = 0.037) and in farms that had flooding or waterlogging conditions (OR = 11.95, 95% CI = 1.39-102.6, P = 0.024) when compared to the odds of the disease in farms that did not have the above conditions. The odds of the disease in farms that treated their soils with lime were significantly lower (OR = 0.028, 95% CI = 0.003-0.29, P = 0.003) compared to the odds in those that did not. CONCLUSIONS The risk factors for the exposure to B. pseudomallei highlighted above may have contributed to the occurrence of melioidosis in animals in the study farms. SIGNIFICANCE AND IMPACT OF THE STUDY Information from the study may be helpful in planning control measures against melioidosis and have improved understanding of the epidemiology of the disease in livestock farms.
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Affiliation(s)
- H I Musa
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor, Malaysia.,Department of Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, University of Maiduguri, Borno State, Nigeria
| | - L Hassan
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor, Malaysia
| | - Z H Shamsuddin
- Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, Selangor, Malaysia
| | | | - Z Zakaria
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor, Malaysia
| | - S Abdul Aziz
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor, Malaysia
| | - R F N Rachmat
- Department of Veterinary Services, Wisma Tani, Putrajaya, Malaysia
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