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Badten AJ, Torres AG. Burkholderia pseudomallei Complex Subunit and Glycoconjugate Vaccines and Their Potential to Elicit Cross-Protection to Burkholderia cepacia Complex. Vaccines (Basel) 2024; 12:313. [PMID: 38543947 PMCID: PMC10975474 DOI: 10.3390/vaccines12030313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 04/01/2024] Open
Abstract
Burkholderia are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. B. pseudomallei and B. mallei, the etiological agents of melioidosis and glanders, respectively, are the two clinically relevant members of the B. pseudomallei complex (Bpc). The development of vaccines against Bpc species has been accelerated in recent years, resulting in numerous promising subunits and glycoconjugate vaccines incorporating a variety of antigens. However, a second group of pathogenic Burkholderia species exists known as the Burkholderia cepacia complex (Bcc), a group of opportunistic bacteria which tend to affect individuals with weakened immunity or cystic fibrosis. To date, there have been few attempts to develop vaccines to Bcc species. Therefore, the primary goal of this review is to provide a broad overview of the various subunit antigens that have been tested in Bpc species, their protective efficacy, study limitations, and known or suspected mechanisms of protection. Then, we assess the reviewed Bpc antigens for their amino acid sequence conservation to homologous proteins found in Bcc species. We propose that protective Bpc antigens with a high degree of Bpc-to-Bcc sequence conservation could serve as components of a pan-Burkholderia vaccine capable of protecting against both disease-causing groups.
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Affiliation(s)
- Alexander J. Badten
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA;
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Alfredo G. Torres
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA;
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
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2
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Wagner GE, Berner A, Lipp M, Kohler C, Assig K, Lichtenegger S, Saqib M, Müller E, Trinh TT, Gad AM, Söffing HH, Ehricht R, Laroucau K, Steinmetz I. Protein Microarray-Guided Development of a Highly Sensitive and Specific Dipstick Assay for Glanders Serodiagnostics. J Clin Microbiol 2023; 61:e0123422. [PMID: 36541753 DOI: 10.1128/jcm.01234-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Burkholderia mallei, the causative agent of glanders, is a clonal descendant of Burkholderia pseudomallei, the causative agent of melioidosis, which has lost its environmental reservoir and has a restricted host range. Despite limitations in terms of sensitivity and specificity, complement fixation is still the official diagnostic test for glanders. Therefore, new tools are needed for diagnostics and to study the B. mallei epidemiology. We recently developed a highly sensitive serodiagnostic microarray test for human melioidosis based on the multiplex detection of B. pseudomallei proteins. In this study, we modified our array tests by using anti-horse IgG conjugate and tested sera from B. mallei-infected horses (n = 30), negative controls (n = 39), and horses infected with other pathogens (n = 14). Our array results show a sensitivity of 96.7% (confidence interval [CI] 85.5 to 99.6%) and a specificity of 100.0% (CI, 95.4 to 100.0%). The reactivity pattern of the positive sera on our array test allowed us to identify a set of 12 highly reactive proteins of interest for glanders diagnosis. The B. mallei variants of the three best protein candidates were selected for the development of a novel dipstick assay. Our point-of-care test detected glanders cases in less than 15 min with a sensitivity of 90.0% (CI, 75.7 to 97.1%) and a specificity of 100.0% (CI, 95.4 to 100.0%). The microarray and dipstick can easily be adopted for the diagnosis of both B. mallei and B. pseudomallei infections in different animals. Future studies will show whether multiplex serological testing has the potential to differentiate between these pathogens.
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3
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Brangsch H, Singha H, Laroucau K, Elschner M. Sequence-based detection and typing procedures for Burkholderia mallei: Assessment and prospects. Front Vet Sci 2022; 9:1056996. [PMID: 36452150 PMCID: PMC9703372 DOI: 10.3389/fvets.2022.1056996] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 10/26/2022] [Indexed: 10/28/2023] Open
Abstract
Although glanders has been eradicated in most of the developed world, the disease still persists in various countries such as Brazil, India, Pakistan, Bangladesh, Nepal, Iran, Bahrain, UAE and Turkey. It is one of the notifiable diseases listed by the World Organization for Animal Health. Occurrence of glanders imposes restriction on equestrian events and restricts equine movement, thus causing economic losses to equine industry. The genetic diversity and global distribution of the causing agent, Burkholderia (B.) mallei, have not been assessed in detail and are complicated by the high clonality of this organism. Among the identification and typing methods, PCR-based methods for distinguishing B. mallei from its close relative B. pseudomallei as well as genotyping using tandem repeat regions (MLVA) are established. The advent and continuous advancement of the sequencing techniques and the reconstruction of closed genomes enable the development of genome guided epidemiological tools. For achieving a higher genomic resolution, genotyping methods based on whole genome sequencing data can be employed, like genome-wide single nucleotide polymorphisms. One of the limitations in obtaining complete genomic sequences for further molecular characterization of B. mallei is its high GC content. In this review, we aim to provide an overview of the widely used detection and typing methods for B. mallei and illustrate gaps that still require development. The genomic features of Burkholderia, their high homology and clonality will be first described from a comparative genomics perspective. Then, the commonly used molecular detection (PCR systems) and typing systems (e.g., multilocus sequence typing, variable number of tandem repeat analysis) will be presented and put in perspective with recently developed genomic methods. Also, the increasing availability of B. mallei genomic sequences and evolution of the sequencing methods offers exciting prospects for further refinement of B. mallei typing, that could overcome the difficulties presently encountered with this particular bacterium.
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Affiliation(s)
- Hanka Brangsch
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institut – Federal Research Institute for Animal Health, Jena, Germany
| | | | - Karine Laroucau
- Bacterial Zoonosis Unit, Animal Health Laboratory, French Food Agency (Anses), Maisons-Alfort, France
| | - Mandy Elschner
- Institute of Bacterial Infections and Zoonoses, Friedrich-Loeffler-Institut – Federal Research Institute for Animal Health, Jena, Germany
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4
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Falcão MVD, Laroucau K, Vorimore F, Deshayes T, Santana VLA, Silva KPC, do Nascimento SA, de Castro RS, Araújo FR, Mota RA. Molecular characterization of Burkholderia mallei strains isolated from horses in Brazil (2014-2017). Infect Genet Evol 2022; 99:105250. [PMID: 35183750 DOI: 10.1016/j.meegid.2022.105250] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 11/24/2021] [Accepted: 02/14/2022] [Indexed: 05/01/2023]
Abstract
Glanders is an infectious zoonosis caused by Burkholderia (B.) mallei that mainly affects equids. The objective of this work was to provide additional knowledge on the diversity of the strains circulating in Brazil. Six Burkholderia mallei isolates obtained during necropsies of glanderous horses between 2014 and 2017 in two different states (Pernambuco and Alagoas) were analyzed by polymerase chain reaction-high-resolution melting (PCR-HRM). While four strains (9902 RSC, BM_campo 1, BM_campo 3 and UFAL2) clustered in the L3B2 branch, which already includes the Brazilian 16-2438_BM#8 strain, two strains (BM_campo 2.1 and BM_campo 2.2) clustered within the L3B3sB3 branch, which mostly includes older isolates, from Europe and the Middle East. Whole genome sequencing of two of these strains (UFAL2 and BM_campo 2.1), belonging to different branches, confirmed the HRM typing results and refined the links between the strains, including the description of the L3B3Sb3Gp1SbGp1 genotype, never reported so far for contemporary strains. These results suggest different glanders introduction events in Brazil, including a potential link with strains of European origin, related to colonization or trade.
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Affiliation(s)
- Marcus V D Falcão
- Federal Rural University of Pernambuco, Department of Veterinary Medicine, Recife, Pernambuco, Brazil
| | - Karine Laroucau
- Bacterial Zoonoses unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Maisons-Alfort, France
| | - Fabien Vorimore
- Bacterial Zoonoses unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Maisons-Alfort, France
| | - Thomas Deshayes
- Bacterial Zoonoses unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Maisons-Alfort, France
| | - Vania L A Santana
- Ministry of Agriculture, Livestock and Food Supply, Recife, Pernambuco, Brazil
| | - Karla P C Silva
- Federal University of Alagoas, Department of Veterinary Medicine, Maceió, Alagoas, Brazil
| | - Sergio A do Nascimento
- Federal Rural University of Pernambuco, Department of Veterinary Medicine, Recife, Pernambuco, Brazil
| | - Roberto S de Castro
- Federal Rural University of Pernambuco, Department of Veterinary Medicine, Recife, Pernambuco, Brazil
| | - Flabio R Araújo
- Embrapa Gado de Corte, Campo Grande, Mato Grosso do Sul, Brazil
| | - Rinaldo A Mota
- Federal Rural University of Pernambuco, Department of Veterinary Medicine, Recife, Pernambuco, Brazil.
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5
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Wernery U, Chan E, Raghavan R, Teng JLL, Syriac G, Siu SY, Joseph M, Yeung ML, Jia L, Cai JP, Chiu TH, Lau SKP, Woo PCY. Development of a sensitive competitive enzyme-linked immunosorbent assay for serodiagnosis of Burkholderia mallei, a Tier 1 select agent. PLoS Negl Trop Dis 2021; 15:e0010007. [PMID: 34932554 PMCID: PMC8691619 DOI: 10.1371/journal.pntd.0010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 11/18/2021] [Indexed: 11/19/2022] Open
Abstract
Glanders is a highly contagious and potentially serious disease caused by Burkholderia mallei, a Tier 1 select agent. In this study, we raised a monoclonal antibody (mAb) against the lipopolysaccharide (LPS) of B. mallei and developed a competitive enzyme-linked immunosorbent assay (cELISA) for B. mallei infection. Using the titrated optimal conditions of B. mallei-LPS (2 ng) for microtiter plate coating, sample serum dilution at 1:20 and 3.5 ng/μL anti-LPS mAb B5, the cutoff value of the cELISA was determined using serum samples from 136 glanders-free seronegative horses in Hong Kong. All calculated percentage inhibition (PI) values from these seronegative samples were below 39.6% inhibition (1.5 standard deviations above mean PI) and was used as the cutoff value. The diagnostic sensitivity of the developed LPS-based cELISA was first evaluated using sera from donkeys and mice inoculated with B. mallei. An increasing trend of PI values above the defined cELISA cutoff observed in the donkey and mouse sera suggested positive detection of anti-LPS antibodies. The sensitivity and specificity of the LPS-based cELISA was further evaluated using 31 serologically positive horse sera from glanders outbreaks in Bahrain and Kuwait, of which 30 were tested positive by the cELISA; and 21 seronegative horse sera and 20 seronegative donkey sera from Dubai, of which all were tested negative by the cELISA. A cELISA with high sensitivity (97.2%) and specificity (100%) for the detection of B. mallei antibodies in different animals was developed. Glanders is a highly contagious and life-threatening disease caused by Burkholderia mallei, a Tier 1 select agent, with no available vaccine. The disease is endemic in the Middle East, Asia, Africa and South America with sporadic outbreaks and mainly occurs in horses, donkeys and mules, although it has also been reported in camels, tigers, lions, and even humans. As the bacterium is not easily isolated from clinical specimens and correct identification based on clinical signs is difficult, it is thus important to develop serological tests which can quickly diagnose B. mallei infection. In this study, we generated a monoclonal antibody against B. mallei lipopolysaccharide and used it to develop a competitive enzyme-linked immunosorbent assay (cELISA) for the serodiagnosis of B. mallei infection. The developed cELISA was optimized and evaluated using glanders-free and glanders-positive horses, donkeys and mice from Hong Kong and the Middle East, and was shown to be highly sensitive and specific for the detection of glanders in different animals. A simple and inexpensive test to allow for the early detection and diagnosis of suspected clinical cases as well as the screening of apparently asymptomatic animals will be helpful in controlling the spread and elimination of the disease.
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Affiliation(s)
- Ulrich Wernery
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
- * E-mail: (UW); (PCYW)
| | - Elaine Chan
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Rekha Raghavan
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
| | - Jade L. L. Teng
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
| | - Ginu Syriac
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
| | - Sing-Yung Siu
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Marina Joseph
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
| | - Man-Lung Yeung
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
| | - Lilong Jia
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Jian-Piao Cai
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Tsz-Ho Chiu
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Susanna K. P. Lau
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
| | - Patrick C. Y. Woo
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
- State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
- * E-mail: (UW); (PCYW)
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6
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Wang G, Glaser L, Scott NE, Fathy Mohamed Y, Ingram R, Laroucau K, Valvano MA. A glycoengineered antigen exploiting a conserved protein O-glycosylation pathway in the Burkholderia genus for detection of glanders infections. Virulence 2021; 12:493-506. [PMID: 33509023 PMCID: PMC7849680 DOI: 10.1080/21505594.2021.1876440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
We recently described a protein O-glycosylation pathway conserved in all species of the Burkholderia genus that results in the synthesis and incorporation of a trisaccharide glycan to membrane-exported proteins. Here, we exploited this system to construct and evaluate a diagnostic tool for glanders. Burkholderia mallei, the causative agent of glanders, is a highly infectious and fatal zoonotic pathogen that infects horses, mules, donkeys, and occasionally humans. A highly sensitive and specific diagnostic tool is crucial for the control, elimination, and eradication of B. mallei infections. We constructed plasmids carrying synthetic genes encoding a modified, previously unannotated Burkholderia glycoprotein containing three glycosylation sequons fused to the cholera toxin B-subunit. The resulting proteins were glycosylated in the B. cenocepacia K56-2 parental strain, but not in glycosylation-deficient mutants, as determined by SDS-PAGE and fluorescent lectin blots. One of these glycoproteins was used as an antigen in ELISA and western blots to screen a panel of serum samples collected from glanders-infected and healthy horses, which were previously investigated by complement fixation test and indirect ELISA based on a semi-purified fraction of B. mallei. We show that ELISA and western blot assays based on our glycoprotein antigen provide 100% specificity, with a sensitivity greater than 88%. The glycoprotein antigen was recognized by serum samples collected from patients infected with B. pseudomallei, B. mallei, B. multivorans, and B. cenocepacia. Our results indicate that protein O-glycosylation in Burkholderia can be exploited as a biomarker for diagnosis of Burkholderia-associated infections.
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Affiliation(s)
- Guanbo Wang
- Wellcome-Wolfson Institute of Experimental Medicine, Queen's University Belfast , Belfast, UK
| | - Lena Glaser
- Wellcome-Wolfson Institute of Experimental Medicine, Queen's University Belfast , Belfast, UK
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity , Melbourne, Australia
| | - Yasmine Fathy Mohamed
- Wellcome-Wolfson Institute of Experimental Medicine, Queen's University Belfast , Belfast, UK.,Department of Microbiology and Immunology, Faculty of Pharmacy, Alexandria University , Alexandria, Egypt
| | - Rebecca Ingram
- Wellcome-Wolfson Institute of Experimental Medicine, Queen's University Belfast , Belfast, UK
| | - Karine Laroucau
- University Paris-Est, French Agency for Food, Environmental and Occupational Health & Safety (Anses), Animal Health Laboratory , Maisons-Alfort, Cedex, France
| | - Miguel A Valvano
- Wellcome-Wolfson Institute of Experimental Medicine, Queen's University Belfast , Belfast, UK
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7
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Abstract
The genus Burkholderia includes a wide range of Gram-negative bacterial species some of which are pathogenic to humans and other vertebrates. The most pathogenic species are Burkholderia mallei, Burkholderia pseudomallei, and the members of the Burkholderia cepacia complex (Bcc). B. mallei and B. pseudomallei, the cause of glanders and melioidosis, respectively, are considered potential bioweapons. The Bcc comprises a subset of Burkholderia species associated with respiratory infections in people with chronic granulomatous disease and cystic fibrosis. Antimicrobial treatment of Burkholderia infections is difficult due to the intrinsic multidrug antibiotic resistance of these bacteria; prophylactic vaccines provide an attractive alternative to counteract these infections. Although commercial vaccines against Burkholderia infections are still unavailable, substantial progress has been made over recent years in the development of vaccines against B. pseudomallei and B. mallei. This review critically discusses the current advances in vaccine development against B. mallei, B. pseudomallei, and the Bcc.
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Affiliation(s)
| | | | - Miguel A. Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast BT9 7BL, UK; (G.W.); (P.Z.)
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8
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Abreu DC, Gomes AS, Tessler DK, Chiebao DP, Fava CD, Romaldini AHCN, Araujo MC, Pompei J, Marques GF, Harakava R, Pituco EM, Nassar AFC. Systematic monitoring of glanders-infected horses by complement fixation test, bacterial isolation, and PCR. Vet Anim Sci 2020; 10:100147. [PMID: 33089006 DOI: 10.1016/j.vas.2020.100147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/28/2020] [Accepted: 09/30/2020] [Indexed: 02/06/2023] Open
Abstract
A modified PCR protocol improved the diagnostic sensibility for glanders. Horses with chronic glanders disease may show false negative serology results. The cold CFT is recommended in Brazilian equine health program. Burkholderia mallei isolation and detection were performed in São Paulo state, Brazil.
Glanders is an equine zoonosis caused by Burkholderia mallei that is responsible for considerable economic loss. Complement fixation testing (CFT) using warm or cold incubation are recommended by the OIE, but many routinely used detection tests may present misleading results. To increase accuracy of glanders diagnosis and establish an appropriate protocol in collaboration with the National Equine Health Program, seven horses positive for glanders kept in isolation in Brazil were examined fortnightly by CFT, microbiological screening, and molecular testing. Warm and cold serologies with USDA and c.c.Pro antigens, respectively, were performed on 132 samples using the US Department of Agriculture protocol. The warm and cold serologies showed, respectively,12.9% and 17.3% seroreactive, 85.7% and 65.2% non-reactive, 0.8% and 3% inconclusive, and 0% and 2.3% anticomplementary. The agreement of CFT protocols was moderate. Of 213 clinical samples submitted to selective culture (167 nasal swabs, 5 ocular swabs, 3 lymph node punctures, and 38 tissue samples from four horses that died), 1.9% tested positive for B. mallei. Fourteen samples and one nasal swab (7%) tested positive with PCR. Cold CFT with the USDA and c.c.Pro antigens, in combination with PCR to increase sensitivity, may be useful for diagnosis of chronic glanders.
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Laroucau K, Aaziz R, Vorimore F, Varghese K, Deshayes T, Bertin C, Delannoy S, Sami AM, Al Batel M, El Shorbagy M, Almutawaa KAW, Alanezi SJ, Alazemi YSN, Guernier-Cambert V, Wernery U. A genetic variant of Burkholderia mallei detected in Kuwait: Consequences for the PCR diagnosis of glanders. Transbound Emerg Dis 2020; 68:960-963. [PMID: 33245616 DOI: 10.1111/tbed.13777] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/02/2020] [Accepted: 08/04/2020] [Indexed: 11/26/2022]
Abstract
Glanders is a contagious zoonotic disease caused by Burkholderia mallei. Following the detection of glanders positive horses using the OIE complement fixation test, the tissues of two horses were analysed by PCR. While PCR systems targeting the Burkholderia pseudomallei complex gave positive signals, the species-specific PCR systems targeting B. mallei (fliP-IS407A) and B. pseudomallei (orf11)-the OIE recommended targets-resulted in negative signals. However, the presence of B. mallei in these tissues was confirmed with a recently described B. mallei-specific real-time PCR system and genotyping with MLST- and SNP-based methods, performed on the most positive tissue, identified a genotype closely related to B. mallei strains recently isolated in the Middle East. This study leads to recommendations regarding the use of PCR systems for the molecular diagnosis of glanders, especially in regions where the circulating B. mallei strains have not yet been fully genetically characterized.
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Affiliation(s)
- Karine Laroucau
- Laboratory for Animal Health, Bacterial Zoonosis Unit, European and OIE Reference Laboratory for Glanders, Paris-Est University, ANSES, Maisons-Alfort, France
| | - Rachid Aaziz
- Laboratory for Animal Health, Bacterial Zoonosis Unit, European and OIE Reference Laboratory for Glanders, Paris-Est University, ANSES, Maisons-Alfort, France
| | - Fabien Vorimore
- Laboratory for Animal Health, Bacterial Zoonosis Unit, European and OIE Reference Laboratory for Glanders, Paris-Est University, ANSES, Maisons-Alfort, France
| | - Koshy Varghese
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Thomas Deshayes
- Laboratory for Animal Health, Bacterial Zoonosis Unit, European and OIE Reference Laboratory for Glanders, Paris-Est University, ANSES, Maisons-Alfort, France
| | - Claire Bertin
- Laboratory for Animal Health, Bacterial Zoonosis Unit, European and OIE Reference Laboratory for Glanders, Paris-Est University, ANSES, Maisons-Alfort, France
| | - Sabine Delannoy
- Food Research Laboratory, IdentyPath Platform, University Paris-Est, ANSES, Maisons-Alfort, France
| | - Attia M Sami
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Maha Al Batel
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Mamdouh El Shorbagy
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Khaled A W Almutawaa
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Saad J Alanezi
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Yousef S N Alazemi
- Veterinary Diagnostic Laboratory Centre & Animal Health Department, Agriculture Affairs & Fish Resources Authority (PAAF), Kuwait
| | - Vanina Guernier-Cambert
- Agricultural Research Service, National Animal Disease Center, United States Department of Agriculture, Ames, IA, USA
| | - Ulrich Wernery
- Central Veterinary Research Laboratory, OIE Reference Laboratory for Glanders, Dubai, United Arab Emirates
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10
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Falcão MVD, Silveira PPM, Santana VLA, da Rocha LO, Chaves KP, Mota RA. First record of Burkholderia mallei Turkey 10 strain originating from glanderous horses from Brazil. Braz J Microbiol 2019; 50:1125-1127. [PMID: 31321739 DOI: 10.1007/s42770-019-00113-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 06/25/2019] [Indexed: 11/30/2022] Open
Abstract
Burkholderia (B.) mallei is the causative agent of glanders in Equidae. This study describes the first record of the Turkey 10 strain of B. mallei in glanderous horses in Northeastern of Brazil. This description should contribute to the future actions of diagnosis, control, and eradication of this disease in Brazil.
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Affiliation(s)
- Marcus Vinícius D Falcão
- Department of Veterinary Medicine, Laboratory of Infectious Diseases of Domestic Animals, Federal Rural University of Pernambuco, Manoel de Medeiros street, w/n, Dois Irmãos, Recife, PE, CEP: 52171-900, Brazil.
| | - Pedro P M Silveira
- Federal Superintendence of Agriculture, Livestock and Supply in the State of Pernambuco, Ministry of Agriculture, Livestock and Supply, General San Martin Avenue, 1000, Bongi, Recife, PE, CEP: 50630-060, Brazil
| | - Vania L A Santana
- Federal Superintendence of Agriculture, Livestock and Supply in the State of Pernambuco, Ministry of Agriculture, Livestock and Supply, General San Martin Avenue, 1000, Bongi, Recife, PE, CEP: 50630-060, Brazil
| | - Larissa O da Rocha
- Academic Unit of Viçosa, Laboratory of Infectious Diseases of Domestic Animals, Federal University of Alagoas, Manoel Severino Barbosa, w/n, Bom Sucesso, Viçosa, AL, CEP: 57309-005, Brazil
| | - Karla P Chaves
- Academic Unit of Viçosa, Laboratory of Infectious Diseases of Domestic Animals, Federal University of Alagoas, Manoel Severino Barbosa, w/n, Bom Sucesso, Viçosa, AL, CEP: 57309-005, Brazil
| | - Rinaldo A Mota
- Department of Veterinary Medicine, Laboratory of Infectious Diseases of Domestic Animals, Federal Rural University of Pernambuco, Manoel de Medeiros street, w/n, Dois Irmãos, Recife, PE, CEP: 52171-900, Brazil
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11
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Saxena A, Pal V, Tripathi NK, Goel AK. A real-time loop mediated isothermal amplification assay for molecular detection of Burkholderia mallei, the aetiological agent of a zoonotic and re-emerging disease glanders. Acta Trop 2019; 194:189-194. [PMID: 30958991 DOI: 10.1016/j.actatropica.2019.04.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/04/2019] [Indexed: 10/27/2022]
Abstract
Burkholderia mallei, a potential biological warfare agent, is the causative agent of an infectious, fatal, and zoonotic disease, called glanders. Accurate and early diagnosis of glanders is important to control the disease lethality and infection spread. Molecular detection of B. mallei is considered strenuous because B. mallei is a subtractive genomic clone of B. pseudomallei. The present study was aimed at development of a real-time LAMP assay for detection of B. mallei. The LAMP assay was highly sensitive and could detect ≥250 fg of genomic DNA of B. mallei and ≥100 copies of recombinant plasmid containing target DNA sequence. In artificially spiked blood and water samples, it could detect ≥2.1 × 103 and ≥4.73 × 102 CFU/mL of B. mallei, respectively. The assay was highly specific for B. mallei as none of the other bacteria used in the study tested positive. The reported LAMP assay being simple and rapid can be a viable alternative to PCR-based glanders diagnostic assays in glanders endemic regions with resource-limited settings.
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Saxena A, Pal V, Tripathi NK, Goel AK. Development of a rapid and sensitive recombinase polymerase amplification‐lateral flow assay for detection ofBurkholderia mallei. Transbound Emerg Dis 2019; 66:1016-1022. [DOI: 10.1111/tbed.13126] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/31/2018] [Accepted: 01/03/2019] [Indexed: 01/10/2023]
Affiliation(s)
- Apoorva Saxena
- Bioprocess Technology Division Defence Research and Development Establishment Gwalior India
| | - Vijai Pal
- Bioprocess Technology Division Defence Research and Development Establishment Gwalior India
| | - Nagesh Kumar Tripathi
- Bioprocess Technology Division Defence Research and Development Establishment Gwalior India
| | - Ajay Kumar Goel
- Bioprocess Technology Division Defence Research and Development Establishment Gwalior India
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Boskani T, Edvinsson B, Wahab T. Development of nineteen Taqman real-time PCR assays for screening and detection of select highly pathogenic bacteria. Infect Ecol Epidemiol 2019. [DOI: 10.1080/20008686.2018.1553462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- Talar Boskani
- Department of Microbiology, Public Health Agency of Sweden, Solna, Sweden
| | - Benjamin Edvinsson
- Department of Microbiology, Public Health Agency of Sweden, Solna, Sweden
- Unit of Freeze Dried and Inhalation, AstraZeneca Sweden Operations, Sweden
| | - Tara Wahab
- Department of Microbiology, Public Health Agency of Sweden, Solna, Sweden
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Laroucau K, Lucia de Assis Santana V, Girault G, Martin B, Miranda da Silveira P, Brasil Machado M, Joseph M, Wernery R, Wernery U, Zientara S, Madani N. First molecular characterisation of a Brazilian Burkholderia mallei strain isolated from a mule in 2016. Infection, Genetics and Evolution 2018; 57:117-120. [DOI: 10.1016/j.meegid.2017.11.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 11/02/2017] [Accepted: 11/12/2017] [Indexed: 11/30/2022]
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Pal V, Saxena A, Singh S, Kumar S, Goel AK. Development of a TaqMan Real-Time Polymerase Chain Reaction Assay for Detection of Burkholderia mallei. J Equine Vet Sci 2017. [DOI: 10.1016/j.jevs.2017.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pal V, Saxena A, Singh S, Goel AK, Kumar JS, Parida MM, Rai GP. Development of a real-time loop-mediated isothermal amplification assay for detection of Burkholderia mallei. Transbound Emerg Dis 2017. [PMID: 28649808 DOI: 10.1111/tbed.12665] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Burkholderia mallei is the aetiological agent of glanders, a highly contagious and re-emerging zoonotic disease. Early diagnosis of glanders is critically important to ensure timely treatment with appropriate antibiotics in humans, and to prevent spread of infection in animals. Molecular detection of B. mallei has always been troublesome because of its genetic similarity with Burkholderia pseudomallei, the causative agent of melioidosis. In present investigation, a set of six B. mallei-specific primers were designed and a simple, rapid, specific and sensitive real-time loop-mediated isothermal amplification (LAMP) assay was developed for detection of B. mallei. The LAMP assay could detect as low as 1 pg of B. mallei genomic DNA and 5.5 × 103 CFU/ml of B. mallei in spiked human blood. The assay was highly specific for B. mallei as it did not cross-react with other bacterial strains used in the study. The established LAMP assay is field adaptable and can be a better and viable alternative to PCR-based techniques for detection of B. mallei in glanders endemic areas with resource-limited settings.
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Affiliation(s)
- V Pal
- Microbiology Division, Defence Research and Development Establishment, Gwalior, India
| | - A Saxena
- Microbiology Division, Defence Research and Development Establishment, Gwalior, India
| | - S Singh
- Microbiology Division, Defence Research and Development Establishment, Gwalior, India
| | - A K Goel
- Biotechnology Division, Defence Research and Development Establishment, Gwalior, India
| | - J S Kumar
- Virology Division, Defence Research and Development Establishment, Gwalior, India
| | - M M Parida
- Virology Division, Defence Research and Development Establishment, Gwalior, India
| | - G P Rai
- Microbiology Division, Defence Research and Development Establishment, Gwalior, India
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Elschner MC, Neubauer H, Sprague LD. The Resurrection of Glanders in a new Epidemiological Scenario: A Beneficiary of “Global Change”. Curr Clin Micro Rpt 2017. [DOI: 10.1007/s40588-017-0058-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Naureen A, Saqib M, Muhammad G, Hussain MH, Asi MN. Comparative Evaluation of Rose Bengal Plate Agglutination Test, Mallein Test, and Some Conventional Serological Tests for Diagnosis of Equine Glanders. J Vet Diagn Invest 2016; 19:362-7. [PMID: 17609344 DOI: 10.1177/104063870701900404] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The Rose Bengal plate agglutination test (RBT) was evaluated for the diagnosis of equine glanders, and its diagnostic efficiency was compared with that of mallein and other serological tests, including indirect hemagglutination test (IHAT), complement fixation test (CFT), and modified counter immunoelectrophoresis test (mCIET). Sera from 70 naturally infected culture-positive, 96 potentially exposed cohorts, and 110 healthy equines were tested. All tests but mCIET showed 100% specificity when testing the sera from glanders-negative equines. The calculated sensitivities of RBT, IHAT, CFT, mCIET, and mallein test when testing culture-positive equines were 90.0, 97.1, 91.4, 81.4, and 75.7%, respectively. The RBT was significantly ( P < 0.05) more sensitive than the mallein test and mCIET. The positive and negative predictive values of each test (RBT, IHAT, CFT, mallein test, and mCIET) were as follows: 100 and 94, 100 and 98.2, 100 and 96.7, 100 and 86.6, and 90.5 and 88.6, respectively. On comparing glandered and nonglandered animals, the highest agreement (0.987) was found between RBT and CFT followed by RBT and IHAT (0.940), RBT and mallein test (0.871), and RBT and mCIET (0.852). Because the RBT is simpler and rapid to perform, the inclusion of the test as a supplementary test for the diagnosis of glanders in field conditions is recommended.
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Affiliation(s)
- Abeera Naureen
- Department of Clinical Medicine and Surgery, University of Agriculture, Faisalabad, 38040 Pakistan.
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Lowe CW, Satterfield BA, Nelson DB, Thiriot JD, Heder MJ, March JK, Drake DS, Lew CS, Bunnell AJ, Moore ES, O'Neill KL, Robison RA. A Quadruplex Real-Time PCR Assay for the Rapid Detection and Differentiation of the Most Relevant Members of the B. pseudomallei Complex: B. mallei, B. pseudomallei, and B. thailandensis. PLoS One 2016; 11:e0164006. [PMID: 27736903 PMCID: PMC5063335 DOI: 10.1371/journal.pone.0164006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 09/19/2016] [Indexed: 11/24/2022] Open
Abstract
The Burkholderia pseudomallei complex classically consisted of B. mallei, B. pseudomallei, and B. thailandensis, but has now expanded to include B. oklahomensis, B. humptydooensis, and three unassigned Burkholderia clades. Methods for detecting and differentiating the B. pseudomallei complex has been the topic of recent research due to phenotypic and genotypic similarities of these species. B. mallei and B. pseudomallei are recognized as CDC Tier 1 select agents, and are the causative agents of glanders and melioidosis, respectively. Although B. thailandensis and B. oklahomensis are generally avirulent, both display similar phenotypic characteristics to that of B. pseudomallei. B. humptydooensis and the Burkholderia clades are genetically similar to the B. pseudomallei complex, and are not associated with disease. Optimal identification of these species remains problematic, and PCR-based methods can resolve issues with B. pseudomallei complex detection and differentiation. Currently, no PCR assay is available that detects the major species of the B. pseudomallei complex. A real-time PCR assay in a multiplex single-tube format was developed to simultaneously detect and differentiate B. mallei, B. pseudomallei, and B. thailandensis, and a common sequence found in B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis. A total of 309 Burkholderia isolates and 5 other bacterial species were evaluated. The assay was 100% sensitive and specific, demonstrated sensitivity beyond culture and GC methods for the isolates tested, and is completed in about an hour with a detection limit between 2.6pg and 48.9pg of gDNA. Bioinformatic analyses also showed the assay is likely 100% specific and sensitive for all 84 fully sequenced B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis strains currently available in GenBank. For these reasons, this assay could be a rapid and sensitive tool in the detection and differentiation for those species of the B. pseudomallei complex with recognized clinical and practical significance.
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Affiliation(s)
- Chinn-Woan Lowe
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Benjamin A. Satterfield
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Daniel B. Nelson
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Joseph D. Thiriot
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Michael J. Heder
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Jordon K. March
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - David S. Drake
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Cynthia S. Lew
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Annette J. Bunnell
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Emily S. Moore
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Kim L. O'Neill
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
| | - Richard A. Robison
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America
- * E-mail:
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Laroucau K, Colaneri C, Jaÿ M, Corde Y, Drapeau A, Durand B, Zientara S, Beck C. Interlaboratory ring trial to evaluate CFT proficiency of European laboratories for diagnosis of glanders in equids. Vet Rec 2016; 178:632. [PMID: 27122499 DOI: 10.1136/vr.103617] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2016] [Indexed: 11/04/2022]
Abstract
To evaluate the routine complement fixation test (CFT) used to detect Burkholderia mallei antibodies in equine sera, an interlaboratory proficiency test was held with 24 European laboratories, including 22 National Reference Laboratories for glanders. The panels sent to participants were composed of sera with or without B mallei antibodies. This study confirmed the reliability of CFT and highlighted its intralaboratory reproducibility. However, the sensitivity of glanders serodiagnosis and laboratory proficiency may be improved by standardising critical reagents, including antigens, and by developing a standard B mallei serum.
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Affiliation(s)
- K Laroucau
- European Union Reference Laboratory for Equine Diseases, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - C Colaneri
- European Union Reference Laboratory for Equine Diseases, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - M Jaÿ
- Bacterial Zoonosis Unit, Paris-Est University, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - Y Corde
- Bacterial Zoonosis Unit, Paris-Est University, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - A Drapeau
- Bacterial Zoonosis Unit, Paris-Est University, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - B Durand
- Epidemiology Unit, Paris-Est University, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - S Zientara
- European Union Reference Laboratory for Equine Diseases, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
| | - C Beck
- European Union Reference Laboratory for Equine Diseases, ANSES, Laboratory for Animal Health, Maisons-Alfort, France
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Dominguez M, Münstermann S, de Guindos I, Timoney P. Equine disease events resulting from international horse movements: Systematic review and lessons learned. Equine Vet J 2015; 48:641-53. [PMID: 26509734 DOI: 10.1111/evj.12523] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 10/14/2015] [Indexed: 12/01/2022]
Abstract
REASONS FOR PERFORMING STUDY An analysis of the factors leading to equine disease events was used to support the development of international recommendations for mitigating the risk of disease dissemination through sport horse movements (high health, high performance - 'HHP' horses). OBJECTIVES A review was undertaken to identify the factors resulting in equine disease events following international movement of horses to draw lessons in support of the development of international recommendations for the safe movements of a specific subpopulation of horses: the HHP sport horses. STUDY DESIGN Systematic review carried out in accordance with the PRISMA statement. METHODS The review covered disease events that occurred from 1995 to 2014, identified from the databases of the World Organisation for Animal Health (OIE) and international surveillance reports. RESULTS Overall, 54 disease events were identified, of which 7 were contained in post arrival quarantine and the others resulted in the introduction of pathogens into importing countries. For 81% of the introductions, the OIE recommendations applicable to the diseases involved had not been complied with. Subclinical infections are a challenge for international trade: 88% of the regulated movements that resulted in introductions involved infected horses that showed no clinical signs at the time of import. Biosecurity and management practices in resident equine populations were identified as important mitigating factors in preventing disease spread to the local horse population. CONCLUSIONS The global increase in international horse movements, if not appropriately regulated and supervised by competent veterinary authorities and respective equine industry partners, could potentially lead to increased global spread of infectious equine diseases. Appropriate mitigation measures and compliance with OIE import recommendations for specific diseases can significantly reduce this risk. The recommendations proposed under the HHP approach take into account the mitigation measures identified by this review as important factors in preventing pathogen introduction and spread.
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Affiliation(s)
- M Dominguez
- World Organisation for Animal Health OIE, Paris, France
| | - S Münstermann
- World Organisation for Animal Health OIE, Paris, France
| | - I de Guindos
- Veterinary Faculty, University of Complutense, Madrid, Spain
| | - P Timoney
- Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, USA
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Schmoock G, Elschner M, Sprague LD. Clear distinction between Burkholderia mallei and Burkholderia pseudomallei using fluorescent motB primers. Acta Vet Scand 2015; 57:13. [PMID: 25887130 PMCID: PMC4364355 DOI: 10.1186/s13028-015-0104-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/24/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A frame-shift mutation in the flagellum motor gene motB coding for the chemotaxis MotB protein of Burkholderia mallei has been utilized to design a conventional duplex PCR assay with fluorescent labelled primers. FINDINGS Species specificity was tested with a panel of 13 Burkholderia type strains. A total of 41 B. mallei field strains, 36 B. pseudomallei field strains, and 1 B. thailandensis field strain from different geographic regions were tested and correctly identified. Testing of 55 non-Burkholderia bacterial species revealed 100% specificity of the assay. The minimum detection limit was 1 pg DNA or 160 GE for B. mallei and 130 GE for B. pseudomallei, respectively. CONCLUSIONS This assay enables the clear distinction between B. mallei and B. pseudomallei/B. thailandensis.
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Affiliation(s)
- Gernot Schmoock
- Friedrich-Loeffler-Institut, Bundesforschungsinstitut für Tiergesundheit, Naumburger Str. 96a, DE-07743, Jena, Germany.
| | - Mandy Elschner
- Friedrich-Loeffler-Institut, Bundesforschungsinstitut für Tiergesundheit, Naumburger Str. 96a, DE-07743, Jena, Germany.
- National and OIE Reference Laboratory for Glanders, Friedrich-Loeffler-Institut, Bundesforschungsinstitut für Tiergesundheit, Naumburger Str. 96a, DE-07743, Jena, Germany.
| | - Lisa D Sprague
- Friedrich-Loeffler-Institut, Bundesforschungsinstitut für Tiergesundheit, Naumburger Str. 96a, DE-07743, Jena, Germany.
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Hunger I, Radosavljevic V, Belojevic G, Rotz LD. Case Study – Germany. NATO Science for Peace and Security Series A: Chemistry and Biology 2013. [PMCID: PMC7121156 DOI: 10.1007/978-94-007-5273-3_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Public health structures in Germany reflect the federal system: health care in general lies within the responsibility of the 16 constituent states and the federal government only acts if a state asks for assistance. There were no bioterror-related intentional releases of biological agents in Germany in recent years. The potentially devastating effects of such an incident require sound public health preparedness planning. The Basic Constitutional Law (Grundgesetz) does not allow the deployment of armed forces within Germany with some rare exceptions. However, there is a well-established civil-military cooperation. The Federal Armed Forces (Bundeswehr) are deployed in humanitarian and multinational UN or NATO crisis containment missions abroad, requiring adequate protection from pathogens and diseases endemic or enzootic to those regions. Both, the military and the civil public health system are complex structures that contain administrative, care giving, medical investigation, and research capabilities in order to cope with natural, accidental or intentional biological incidents.
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Affiliation(s)
- Iris Hunger
- , Weizsacker Center Science & Peace Res., University of Hamburg, Beim Schlump 83, Hamburg, 20144 Germany
| | | | - Goran Belojevic
- Institute of Hygiene and Medical Ecology, Faculty of Medicine, University of Belgrade, Dr. Subotica 8, Belgrade, 11000 Serbia
| | - Lisa D. Rotz
- Centers for Disease Control and Preventi, 1600 Clifton Road, MS E3, Atlanta, 30329-4018 Georgia USA
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Frickmann H, Chantratita N, Gauthier YP, Neubauer H, Hagen RM. DISCRIMINATION OF Burkholderia mallei/pseudomallei FROM Burkholderia thailandensis BY SEQUENCE COMPARISON OF A FRAGMENT OF THE RIBOSOMAL PROTEIN S21 (RPSU) GENE. Eur J Microbiol Immunol (Bp) 2012; 2:148-156. [PMID: 23227305 DOI: 10.1556/eujmi.2.2012.2.8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Discrimination of Burkholderia (B.) pseudomallei and B. mallei from environmental B. thailandensis is challenging. We describe a discrimination method based on sequence comparison of the ribosomal protein S21 (rpsU) gene.The rpsU gene was sequenced in ten B. pseudomallei, six B. mallei, one B. thailandensis reference strains, six isolates of B. pseudomallei, and 37 of B. thailandensis. Further rpsU sequences of six B. pseudomallei, three B. mallei, and one B. thailandensis were identified via NCBI GenBank. Three to four variable base-positions were identified within a 120-base-pair fragment, allowing discrimination of the B. pseudomallei/mallei-cluster from B. thailandensis, whose sequences clustered identically. All B. mallei and three B. pseudomallei sequences were identical, while 17/22 B. pseudomallei strains differed in one nucleotide (78A>C). Sequences of the rpsU fragment of 'out-stander' reference strains of B. cepacia, B. gladioli, B. plantarii, and B. vietnamensis clustered differently.Sequence comparison of the described rpsU gene fragment can be used as a supplementary diagnostic procedure for the discrimination of B. mallei/pseudomallei from B. thailandensis as well as from other species of the genus Burkholderia, keeping in mind that it does not allow for a differentiation between B. mallei and B. pseudomallei.
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Affiliation(s)
- H Frickmann
- Department of Tropical Medicine at the Bernhard Nocht Institute, German Armed Forces Hospital Hamburg, Germany ; Institute for Medical Microbiology, Virology and Hygiene, University of Rostock Hospital, Rostock, Germany
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Khan I, Wieler LH, Melzer F, Elschner MC, Muhammad G, Ali S, Sprague LD, Neubauer H, Saqib M. Glanders in animals: a review on epidemiology, clinical presentation, diagnosis and countermeasures. Transbound Emerg Dis 2012; 60:204-21. [PMID: 22630609 DOI: 10.1111/j.1865-1682.2012.01342.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glanders or farcy, caused by Burkholderia mallei, is an infectious and zoonotic disease of solipeds. Horses, donkeys and mules are the only known natural reservoir of B. mallei. Although glanders has been eradicated from most countries, it has regained the status of a re-emerging disease because of the numerous recent outbreaks. Pre-symptomatic or carrier animals are the potential source of infection for the healthy equine population and play a crucial role in the spreading of the infectious agent. Glanders is characterized by ulcerating nodular lesions of the skin and mucous membrane. Generalized symptoms include fever, malaise, depression, cough, anorexia and weight loss. Burkholderia mallei can invade its host through mucous membranes, gastrointestinal tract and the integument. Its virulence mechanisms and pathogenesis are not yet completely understood. A major problem when using serological tests for diagnosing glanders is the occurrence of false-positive and false-negative results leading to difficulties in international trade with equids and to the spread of glanders to disease-free regions. Moreover, poor tests critically result in poor control of disease. These tests are not only incapable of discriminating between B. mallei and B. pseudomallei antibodies, they are also unable to differentiate between malleinized and naturally infected animals. Combined use of both serological and molecular detection methods increases the detection rate of glanders. Countermeasures against glanders include early detection of disease in susceptible animals, stringent quarantine measures, testing and safe destruction of infected carcasses, adequate compensation to the animal owners, disinfection of infected premises and awareness about glanders and the zoonotic implications through veterinary extension services. An account of the clinical picture and successful experimental therapy of spontaneous equine glanders is also given.
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Affiliation(s)
- I Khan
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Bacterial Infections and Zoonoses, Jena, Germany.
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Wernery U, Wernery R, Joseph M, Al-Salloom F, Johnson B, Kinne J, Jose S, Jose S, Tappendorf B, Hornstra H, Scholz HC. Natural Burkholderia mallei infection in Dromedary, Bahrain. Emerg Infect Dis 2012; 17:1277-9. [PMID: 21762586 PMCID: PMC3381376 DOI: 10.3201/eid1707.110222] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We confirm a natural infection of dromedaries with glanders. Multilocus variable number tandem repeat analysis of a Burkholderia mallei strain isolated from a diseased dromedary in Bahrain revealed close genetic proximity to strain Dubai 7, which caused an outbreak of glanders in horses in the United Arab Emirates in 2004.
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Affiliation(s)
- Ulrich Wernery
- Central Veterinary Research Laboratory, Dubai, United Arab Emirates
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Khan I, Wieler LH, Melzer F, Gwida M, Santana VLDA, de Souza MMA, Saqib M, Elschner MC, Neubauer H. Comparative evaluation of three commercially available complement fixation test antigens for the diagnosis of glanders. Vet Rec 2011; 169:495. [PMID: 21896565 DOI: 10.1136/vr.d5410] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The sensitivity and specificity of three commercially available complement fixation test (CFT) antigens from c.c.pro (c.c.pro), Central Veterinary Institute of Wageningen UR (CIDC) and the United States Department of Agriculture (USDA) were comparatively evaluated by testing 410 sera collected from glanders-endemic and non-endemic areas (200 true-negative randomly collected sera and 210 sera collected from experimentally immunised animals (12 rabbits, 19 horses), clinically positive (135) and culture-positive (44) horses, donkeys and mules). Immunoblotting (IB) was used as the gold standard test. Highest sensitivity was shown for the CIDC antigen (100 per cent) followed by the c.c.pro antigen (99.39 per cent). However, the USDA antigen showed substantially less (p<0.05) sensitivity (62.19 per cent). Highest specificity was found for the USDA antigen (100 per cent) followed by the CIDC (97.5 per cent) and c.c.pro antigen (96.5 per cent). Positive and negative predictive values (assumed glanders prevalence of <0.1 per cent) for each antigen were calculated to be 95.88 and 99.48 (c.c.pro), 97.04 and 100 (CIDC), 100 and 76.33 per cent (USDA), respectively. Almost perfect agreement (0.96) was found between CFT using either c.c.pro or CIDC and IB.
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Affiliation(s)
- I Khan
- Federal Research Institute for Animal Health, Naumburger Strasse 96a, 07743 Jena, Germany.
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Hagen RM, Frickmann H, Elschner M, Melzer F, Neubauer H, Gauthier YP, Racz P, Poppert S. Rapid identification of Burkholderia pseudomallei and Burkholderia mallei by fluorescence in situ hybridization (FISH) from culture and paraffin-embedded tissue samples. Int J Med Microbiol 2011; 301:585-90. [PMID: 21658996 DOI: 10.1016/j.ijmm.2011.04.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/12/2011] [Accepted: 04/20/2011] [Indexed: 11/18/2022] Open
Abstract
We evaluated newly developed probes for rapid identification of Burkholderia (B.) pseudomallei and B. mallei and differentiation from B. thailandensis by fluorescence in situ hybridization (FISH). FISH correctly identified 100% of the tested B. pseudomallei (11), B. mallei (11), and B. thailandensis (1) strains, excluded 100% of all tested negative controls (61), and allowed demonstration of B. pseudomallei infection in a paraffin-embedded spleen tissue sample of an experimentally infected mouse.
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Affiliation(s)
- Ralf M Hagen
- Department for Tropical Medicine at the Bernhard Nocht Institute, Bundeswehr Hospital Hamburg, Bernhard-Nocht-Strasse, Germany.
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Merwyn S, Kumar S, Agarwal GS, Rai GP. Evaluation of PCR, DNA hybridization and immunomagnetic separation - PCR for detection of Burkholderia mallei in artificially inoculated environmental samples. Indian J Microbiol 2010; 50:172-8. [PMID: 23100824 DOI: 10.1007/s12088-010-0003-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Accepted: 12/02/2008] [Indexed: 11/28/2022] Open
Abstract
Glanders is highly contagious disease of equines, caused by Burkholderia mallei. The disease though rare, can be transmitted to humans. Here, we report a strategy for rapid detection of B. mallei from environmental samples. Different bacteriological media were evaluated and brain heart infusion broth medium with selective supplements (BHIB-SS) of penicillin (200 U/ml) and crystal violet (1:10,00000) was found to support the maximum growth of B. mallei even in the presence of other bacteria like Escherichia coli and Staphylococcus aureus. A polymerase chain reaction (PCR) and a DNA hybridization method was standardized for 823 bp specific dNA sequence of B. mallei. To enable the quicker and direct enrichment of B. mallei bacteria from environmental samples, an immunomagnetic separation (IMS) method was also standardized. Water, husk, grass and gram samples were artificially contaminated by B. mallei bacteria and after enrichment of B. mallei in BHIB-SS, detection was carried out by PCR and DNA hybridization. PCR was found to be a better method of the two with a detection limit of 10(4)-10(6) CFU/ml (6 h enrichment in BHIB-SS) in water and other particulate matrices. Detection by PCR in the above samples without enrichment in BHIBSS was carried out following IMS where the detection limit was about 1-2 log higher than PCR following enrichment in BHIB-SS. We recommend PCR for 823 bp for detection of B. mallei from environmental samples either following enrichment in BHIB-SS or IMS. IMS-PCR method may be preferred in situations where numbers of B. mallei bacteria are expected to be high and results are required in short time.
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Affiliation(s)
- S Merwyn
- Division of High Containment Facility, Defence Research and Development Establishment, Gwalior, 474 002 India
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Tomaso H, Scholz HC, Al Dahouk S, Splettstoesser WD, Neubauer H, Pfeffer M, Straube E. [Mission oriented diagnostic real-time PCR]. Wien Klin Wochenschr 2007; 119:26-32. [PMID: 17987355 DOI: 10.1007/s00508-007-0858-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
In out of area military missions soldiers are potentially exposed to bacteria that are endemic in tropical areas and can be used as biological agents. It can be difficult to culture these bacteria due to sample contamination, low number of bacteria or pretreatment with antibiotics. Commercial biochemical identification systems are not optimized for these agents which can result in misidentification. Immunological assays are often not commercially available or not specific. Real-time PCR assays are very specific and sensitive and can shorten the time required to establish a diagnosis markedly. Therefore, real-time PCRs for the identification of Bacillus anthracis, Brucella spp., Burkholderia mallei und Burkholderia pseudomallei, Francisella tularensis und Yersinia pestis have been developed. PCR results can be false negative due to inadequate clinical samples, low number of bacteria in samples, DNA degradation, inhibitory substances and inappropriate DNA preparation. Hence, it is crucial to cultivate the organisms as a prerequisite for adequate antibiotic therapy and typing of the agent. In a bioterrorist scenario samples have to be treated according to rules applied in forensic medicine and documentation has to be flawless.
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Sprague LD, Zachariah R, Neubauer H, Wernery R, Joseph M, Scholz HC, Wernery U. Prevalence-dependent use of serological tests for diagnosing glanders in horses. BMC Vet Res 2009; 5:32. [PMID: 19723336 PMCID: PMC2745380 DOI: 10.1186/1746-6148-5-32] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 09/01/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The internationally mandatory complement fixation test (CFT) for testing of equine sera for the absence of glanders has repeatedly led to discrepant results. Not only do "false positive" sera pose a problem for the diagnostician and the animal health authorities but they can also result in significant financial losses for the animal owners.Due to the very low prevalence of glanders in the horse population it is of major importance to use tests with a high specificity to overcome unreliable predictive values. We have compared formalin-fixed B. mallei whole cell antigen and a well characterised mouse monoclonal antibody with regard to their specificity and sensitivity for glanders serodiagnosis using CFT, an indirect (i) and a competitive (c) ELISA platform. RESULTS Our results show that the CFT is still a very reliable technique in horse populations with very low glanders prevalence. The cELISA has a high sensitivity and specificity comparable to that of the CFT. The cELISA offers the possibility for automatisation, can be applied to non-complement fixing sera and used for various host species. CONCLUSION The CFT is still the method of choice for testing horses for the absence of glanders.
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Affiliation(s)
- Lisa D Sprague
- OIE Reference Laboratory for Glanders, Friedrich-Loeffler-Institute, Naumburger Str, 96a, D-07743 Jena, Germany.
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Schmoock G, Ehricht R, Melzer F, Rassbach A, Scholz HC, Neubauer H, Sachse K, Mota RA, Saqib M, Elschner M. DNA microarray-based detection and identification of Burkholderia mallei, Burkholderia pseudomallei and Burkholderia spp. Mol Cell Probes 2009; 23:178-87. [PMID: 19366627 DOI: 10.1016/j.mcp.2009.04.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 04/03/2009] [Accepted: 04/06/2009] [Indexed: 11/17/2022]
Abstract
We developed a rapid oligonucleotide microarray assay based on genetic markers for the accurate identification and differentiation of Burkholderia (B.) mallei and Burkholderia pseudomallei, the agents of glanders and melioidosis, respectively. These two agents were clearly identified using at least 4 independent genetic markers including 16S rRNA gene, fliC, motB and also by novel species-specific target genes, identified by in silico sequence analysis. Specific hybridization signal profiles allowed the detection and differentiation of up to 10 further Burkholderia spp., including the closely related species Burkholderia thailandensis and Burkholderia-like agents, such as Burkholderia cepacia, Burkholderia cenocepacia, Burkholderia vietnamiensis, Burkholderia ambifaria, and Burkholderia gladioli, which are often associated with cystic fibrosis (CF) lung disease. The assay was developed using the easy-to-handle and economical ArrayTube (AT) platform. A representative strain panel comprising 44 B. mallei, 32 B. pseudomallei isolates, and various Burkholderia type strains were examined to validate the test. Assay specificity was determined by examination of 40 non-Burkholderia strains.
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Affiliation(s)
- Gernot Schmoock
- Institute of Bacterial Infections and Zoonoses at the Federal Research Institute for Animal Health (Friedrich-Loeffler-Institut), Naumburger Strasse 96a, 07743 Jena, Germany.
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Schell MA, Ulrich RL, Ribot WJ, Brueggemann EE, Hines HB, Chen D, Lipscomb L, Kim HS, Mrázek J, Nierman WC, Deshazer D. Type VI secretion is a major virulence determinant in Burkholderia mallei. Mol Microbiol 2007; 64:1466-85. [PMID: 17555434 DOI: 10.1111/j.1365-2958.2007.05734.x] [Citation(s) in RCA: 268] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Burkholderia mallei is a host-adapted pathogen and a category B biothreat agent. Although the B. mallei VirAG two-component regulatory system is required for virulence in hamsters, the virulence genes it regulates are unknown. Here we show with expression profiling that overexpression of virAG resulted in transcriptional activation of approximately 60 genes, including some involved in capsule production, actin-based intracellular motility, and type VI secretion (T6S). The 15 genes encoding the major sugar component of the homopolymeric capsule were up-expressed > 2.5-fold, but capsule was still produced in the absence of virAG. Actin tail formation required virAG as well as bimB, bimC and bimE, three previously uncharacterized genes that were activated four- to 15-fold when VirAG was overproduced. Surprisingly, actin polymerization was found to be dispensable for virulence in hamsters. In contrast, genes encoding a T6S system were up-expressed as much as 30-fold and mutations in this T6S gene cluster resulted in strains that were avirulent in hamsters. SDS-PAGE and mass spectrometry demonstrated that BMAA0742 was secreted by the T6S system when virAG was overexpressed. Purified His-tagged BMAA0742 was recognized by glanders antiserum from a horse, a human and mice, indicating that this Hcp-family protein is produced in vivo during infection.
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Affiliation(s)
- Mark A Schell
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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Tiyawisutsri R, Holden MT, Tumapa S, Rengpipat S, Clarke SR, Foster SJ, Nierman WC, Day NP, Peacock SJ. Burkholderia Hep_Hag autotransporter (BuHA) proteins elicit a strong antibody response during experimental glanders but not human melioidosis. BMC Microbiol 2007; 7:19. [PMID: 17362501 DOI: 10.1186/1471-2180-7-19] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 03/15/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The bacterial biothreat agents Burkholderia mallei and Burkholderia pseudomallei are the cause of glanders and melioidosis, respectively. Genomic and epidemiological studies have shown that B. mallei is a recently emerged, host restricted clone of B. pseudomallei. RESULTS Using bacteriophage-mediated immunoscreening we identified genes expressed in vivo during experimental equine glanders infection. A family of immunodominant antigens were identified that share protein domain architectures with hemagglutinins and invasins. These have been designated Burkholderia Hep_Hag autotransporter (BuHA) proteins. A total of 110/207 positive clones (53%) of a B. mallei expression library screened with sera from two infected horses belonged to this family. This contrasted with 6/189 positive clones (3%) of a B. pseudomallei expression library screened with serum from 21 patients with culture-proven melioidosis. CONCLUSION Members of the BuHA proteins are found in other Gram-negative bacteria and have been shown to have important roles related to virulence. Compared with other bacterial species, the genomes of both B. mallei and B. pseudomallei contain a relative abundance of this family of proteins. The domain structures of these proteins suggest that they function as multimeric surface proteins that modulate interactions of the cell with the host and environment. Their effect on the cellular immune response to B. mallei and their potential as diagnostics for glanders requires further study.
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