18 results on '"de Jong, Bouke C."'
Search Results
2. Immunogenicity of antigens from the TbD1 region present in M. africanum and missing from "modern" M. tuberculosis: a cross-sectional study.
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De Jong, Bouke C., Hammond, Abdulrahman, Otu, Jacob K., Antonio, Martin, Adegbola, Richard A., and Ota, Martin O.
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ANTIGENS , *MYCOBACTERIUM tuberculosis , *MYCOBACTERIUM , *IMMUNE response - Abstract
Background: Currently available tools cannot be used to distinguish between sub-species of the M. tuberculosis complex causing latent tuberculosis (TB) infection. M. africanum causes up to half of TB in West- Africa and its relatively lower progression to disease suggests the presence of a large reservoir of latent infection relative to M. tuberculosis. Methods: We assessed the immunogenicity of the TbD1 region, present in M. africanum and absent from "modern" M. tuberculosis, in an ELISPOT assay using cells from confirmed M. africanum or M. tuberculosis infected TB patients without HIV infection in the Gambia. Results: Antigens from the TbD1 region induced IFNγ responses in only 35% patients and did not discriminate between patients infected with M. africanum vs. M. tuberculosis, while PPD induced universally high responses. Conclusions: Further studies will need to assess other antigens unique to M. africanum that may induce discriminatory immune responses. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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3. Mycobacterium africanum elicits an attenuated T cell response to early secreted antigenic target, 6 kDa, in patients with tuberculosis and their household contacts.
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de Jong, Bouke C, Hill, Philip C, Brookes, Roger H, Gagneux, Sebastien, Jeffries, David J, Otu, Jacob K, Donkor, Simon A, Fox, Annette, McAdam, Keith P W J, Small, Peter M, and Adegbola, Richard A
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TUBERCULOSIS microbiology , *BACTERIAL antigens , *BACTERIAL proteins , *INFECTIOUS disease transmission , *COMPARATIVE studies , *GENES , *INTERFERONS , *RESEARCH methodology , *MEDICAL cooperation , *MYCOBACTERIUM , *RESEARCH , *T cells , *TUBERCULIN test , *TUBERCULOSIS , *MICROBIAL virulence , *EVALUATION research , *GENOTYPES ,TUBERCULOSIS transmission - Abstract
Background: Mycobacterium africanum, a member of the M. tuberculosis complex that is infrequently found outside of western Africa, is the cause of up to half of the tuberculosis cases there.Methods: We genotyped mycobacterial isolates obtained from a study of patients with tuberculosis and their household contacts and compared T cell responses and tuberculin skin test results by infecting genotype.Results: The T cell response to early secreted antigenic target, 6 kDa (ESAT-6), was attenuated in patients with tuberculosis (odds ratio [OR], 0.41 [95% confidence interval {CI}, 0.19-0.89]; P = .024) and household contacts (OR, 0.56 [95% CI, 0.38-0.83]; P = .004) infected with M. africanum, compared with the response in those infected with M. tuberculosis. In these same groups, responses to culture filtrate protein, 10 kDa (CFP-10), were nonsignificantly attenuated (P = .22 and P = .16, respectively), as were tuberculin skin test results (P = .30 and P = .46, respectively). Sequencing of region of difference 1 of M. africanum revealed that Rv3879c is a pseudogene in M. africanum; however, this finding does not provide an obvious mechanism for the attenuated ESAT-6 response.Conclusions: This is the first evidence, to our knowledge, that strain differences affect interferon- gamma -based T cell responses. Our findings highlight the need to test new diagnostic candidates against different strains of mycobacteria. Integrating additional immunologic and genomic comparisons of M. tuberculosis and M. africanum into further studies may provide fundamental insights into the interactions between humans and mycobacteria. [ABSTRACT FROM AUTHOR]- Published
- 2006
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4. The use of Kudoh method for culture of Mycobacterium tuberculosis and Mycobacterium africanum in The Gambia.
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Jobarteh, Tijan, Otu, Jacob, Gitteh, Ensa, Mendy, Francis S., Faal-Jawara, Tutty Isatou, Ofori-Anyinam, Boatema, Sarr, Binta, Riley, Abi Janet, Ayorinde, Abigail, de Jong, Bouke C., Kampmann, Beate, Secka, Ousman, and Gehre, Florian
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MYCOBACTERIUM tuberculosis , *CLINICAL pathology , *MYCOBACTERIUM , *MEDICAL laboratories , *TUBERCULOSIS ,DEVELOPING countries - Abstract
Background: Mycobacterium tuberculosis culturing remains the gold standard for laboratory diagnosis of tuberculosis. Tuberculosis remains a great public health problem in developing countries like The Gambia, as most of the methods currently used for bacterial isolation are either time-consuming or costly. Objective: To evaluate the Kudoh swab method in a West African setting in Gambia, with a particular focus on the method's performance when culturing Mycobacterium africanum West Africa 2 (MAF2) isolates. Method: 75 sputum samples were collected in the Greater Banjul Area and decontaminated in parallel with both the standard N-acetyl-L-Cysteine-NaOH (NALC-NaOH) and the Kudoh swab method in the TB diagnostics laboratory in the Medical Research Council Unit The Gambia between 30th December 2017 and 25th February 2018. These samples were subsequently cultured on standard Löwenstein-Jensen and Modified Ogawa media respectively and incubated at 37°C for mycobacterial growth. Spoligotyping was done to determine if the decontamination and culture methods compared could equally detect Mycobacterium tuberculosis, Mycobacterium africanum West Africa 1 and Mycobacterium africanum West Africa 2. Result: Among the 50 smear positives, 35 (70%) were culture-positive with Kudoh and 32 (64%) were culture positive with NALC-NaOH, whilst 7(28%) of the 25 smear negative samples were culture positive with both methods (Table 2). There was no significant difference in recovery between both methods (McNemar's test, p-value = 0.7003), suggesting that the overall positivity rate between the two methods is comparable. There were no differences in time-to-positivity or contamination rate between the methods. However, Kudoh yielded positive cultures that were negative on LJ and vice versa. All findings were irrespective of mycobacterial lineages. Conclusion: The Kudoh method has comparable sensitivity to the NALC-NaOH method for detecting Mycobacterium tuberculosis complex isolates. It is easy to perform and could be an add on option for mycobacterial culture in the field in The Gambia, since it requires less biosafety equipment. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Introduction of Mycobacterium ulcerans disease in the Bankim Health District of Cameroon follows damming of the Mapé River.
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Vandelannoote, Koen, Pluschke, Gerd, Bolz, Miriam, Bratschi, Martin W., Kerber, Sarah, Stinear, Timothy P., and de Jong, Bouke C.
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BURULI ulcer , *SOFT tissue infections , *MYCOBACTERIUM , *MYCOBACTERIAL diseases , *REMOTE-sensing images , *SKIN diseases , *MYCOPLASMA , *MYCOBACTERIA - Abstract
Buruli ulcer (BU) is an emerging ulcerative skin disease caused by infection with Mycobacterium ulcerans. Efforts to control its spread have been hampered by our limited understanding of M. ulcerans reservoirs and transmission, and the factors leading to the emergence of BU disease in a particular region. In this report we investigate an anecdotal link between damming the Mapé River in Cameroon and the emergence of BU in the Health Districts bordering Lake Bankim, the impoundment created by the Mapé dam. We used bacterial population genomics and molecular dating to find compelling support for a 2000 M. ulcerans introduction event that followed about 10 years after the filling of the newly created impoundment in 1988. We compared the genomic reconstructions with high-resolution satellite imagery to investigate what major environmental alterations might have driven the emergence of the new focus. Author summary: Buruli ulcer is a destructive skin and soft tissue infection caused by Mycobacterium ulcerans. Although the disease is not fatal, the infection can often leave patients with significant cosmetic and functional damage to limbs. Currently, one of the major hurdles facing Buruli ulcer control is our incomplete understanding of the factors leading to the emergence of disease in a particular region. In this report we investigate an anecdotal link between the damming of the Mapé River in Cameroon and the emergence of Buruli ulcer in the Health Districts bordering the impoundment created by the Mapé dam. We compare the genome sequences of M. ulcerans isolates recovered from regional Buruli ulcer patients that were identified in a previous molecular epidemiology study. Additionally, we investigate historic satellite imagery to quantify changes in land cover use that followed damming the river. The appearance of Buruli ulcer in the region was found to follow about ten years after the 1988 damming of the Mapé River, supporting the idea that alterations to landscape hydrology can increase BU incidence. While this temporal association does not infer causation, this research helps define the ecological risk factors linked to the spread of BU. [ABSTRACT FROM AUTHOR]
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- 2020
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6. Comparative Genomics Shows That Mycobacterium ulcerans Migration and Expansion Preceded the Rise of Buruli Ulcer in Southeastern Australia.
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Buultjens, Andrew H., Vandelannoote, Koen, Meehan, Conor J., Eddyani, Miriam, de Jong, Bouke C., Fyfe, Janet A. M., Globan, Maria, Tobias, Nicholas J., Porter, Jessica L., Tomita, Takehiro, Tay, Ee Laine, Seemann, Torsten, Howden, Benjamin P., Johnson, Paul D. R., and Stinear, Timothy P.
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GENOMICS , *MYCOBACTERIUM , *BURULI ulcer , *PHYLOGEOGRAPHY , *ENDEMIC diseases - Abstract
Since 2000, cases of the neglected tropical disease Buruli ulcer, caused by infection with Mycobacterium ulcerans, have increased 100-fold around Melbourne (population 4.4 million), the capital of Victoria, in temperate southeastern Australia. The reasons for this increase are unclear. Here, we used whole-genome sequence comparisons of 178 M. ulcerans isolates obtained primarily from human clinical specimens, spanning 70 years, to model the population dynamics of this pathogen from this region. Using phylogeographic and advanced Bayesian phylogenetic approaches, we found that there has been a migration of the pathogen from the east end of the state, beginning in the 1980s, 300 km west to the major human population center around Melbourne. This move was then followed by a signifi- cant increase in M. ulcerans population size. These analyses inform our thinking around Buruli ulcer transmission and control, indicating that M. ulcerans is introduced to a new environment and then expands, rather than it being from the awakening of a quiescent pathogen reservoir. IMPORTANCE Buruli ulcer is a destructive skin and soft tissue infection caused by Mycobacterium ulcerans and is characterized by progressive skin ulceration, which can lead to permanent disfigurement and long-term disability. Despite the majority of disease burden occurring in regions of West and central Africa, Buruli ulcer is also becoming increasingly common in southeastern Australia. Major impediments to controlling disease spread are incomplete understandings of the environmental reservoirs and modes of transmission of M. ulcerans. The significance of our research is that we used genomics to assess the population structure of this pathogen at the Australian continental scale. We have then reconstructed a historical bacterial spread and modeled demographic dynamics to reveal bacterial population expansion across southeastern Australia. These findings provide explanations for the observed epidemiological trends with Buruli ulcer and suggest possible management to control disease spread. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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7. Multiple Introductions and Recent Spread of the Emerging Human Pathogen Mycobacterium ulcerans across Africa.
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Vandelannoote, Koen, Meehan, Conor J., Eddyani, Miriam, Affolabi, Dissou, Phanzu, Delphin Mavinga, Eyangoh, Sara, Jordaens, Kurt, Portaels, Françoise, Mangas, Kirstie, Seemann, Torsten, Marsollier, Laurent, Marion, Estelle, Chauty, Annick, Landier, Jordi, Fontanet, Arnaud, Leirs, Herwig, Stinear, Timothy P., and de Jong, Bouke C.
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BURULI ulcer , *MYCOBACTERIUM , *PATHOGENIC microorganisms , *TROPICAL medicine , *METAGENOMICS , *BIOLOGICAL evolution - Abstract
Buruli ulcer (BU) is an insidious neglected tropical disease. Cases are reported around the world but the rural regions of West and Central Africa are most affected. How BU is transmitted and spreads has remained a mystery, even though the causative agent, Mycobacterium ulcerans, has been known for more than 70 years. Here, using the tools of population genomics, we reconstruct the evolutionary history of M. ulcerans by comparing 165 isolates spanning 48 years and representing 11 endemic countries across Africa. The genetic diversity of African M. ulcerans was found to be restricted due to the bacterium's slow substitution rate coupled with its relatively recent origin. We identified two specific M. ulcerans lineages within the African continent, and inferred that M. ulcerans lineage Mu_A1 existed in Africa for several hundreds of years, unlike lineage Mu_A2, which was introduced much more recently, approximately during the 19th century. Additionally, we observed that specific M. ulcerans epidemic Mu_A1 clones were introduced during the same time period in the three hydrological basins that were well covered in our panel. The estimated time span of the introduction events coincides with the Neo-imperialism period, during which time the European colonial powers divided the African continent among themselves. Using this temporal association, and in the absence of a known BU reservoir or -vector on the continent, we postulate that the so-called "Scramble for Africa" played a significant role in the spread of the disease across the continent. [ABSTRACT FROM AUTHOR]
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- 2017
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8. A Genomic Approach to Resolving Relapse versus Reinfection among Four Cases of Buruli Ulcer.
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Eddyani, Miriam, Vandelannoote, Koen, Meehan, Conor J., Bhuju, Sabin, Porter, Jessica L., Aguiar, Julia, Seemann, Torsten, Jarek, Michael, Singh, Mahavir, Portaels, Françoise, Stinear, Timothy P., and de Jong, Bouke C.
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NUCLEOTIDE sequencing , *BURULI ulcer , *GENOMICS , *MYCOBACTERIUM , *ANTIBIOTICS - Abstract
Background: Increased availability of Next Generation Sequencing (NGS) techniques allows, for the first time, to distinguish relapses from reinfections in patients with multiple Buruli ulcer (BU) episodes. Methodology: We compared the number and location of single nucleotide polymorphisms (SNPs) identified by genomic screening between four pairs of Mycobacterium ulcerans isolates collected at the time of first diagnosis and at recurrence, derived from a collection of almost 5000 well characterized clinical samples from one BU treatment center in Benin. Principal Findings: The findings suggest that after surgical treatment—without antibiotics—the second episodes were due to relapse rather than reinfection. Since specific antibiotics were introduced for the treatment of BU, the one patient with a culture available from both disease episodes had M. ulcerans isolates with a genomic distance of 20 SNPs, suggesting the patient was most likely reinfected rather than having a relapse. Conclusions: To our knowledge, this study is the first to study recurrences in M. ulcerans using NGS, and to identify exogenous reinfection as causing a recurrence of BU. The occurrence of reinfection highlights the contribution of ongoing exposure to M. ulcerans to disease recurrence, and has implications for vaccine development. [ABSTRACT FROM AUTHOR]
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- 2015
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9. Whole Genome Comparisons Suggest Random Distribution of Mycobacterium ulcerans Genotypes in a Buruli Ulcer Endemic Region of Ghana.
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Ablordey, Anthony S., Vandelannoote, Koen, Frimpong, Isaac A., Ahortor, Evans K., Amissah, Nana Ama, Eddyani, Miriam, Durnez, Lies, Portaels, Françoise, de Jong, Bouke C., Leirs, Herwig, Porter, Jessica L., Mangas, Kirstie M., Lam, Margaret M. C., Buultjens, Andrew, Seemann, Torsten, Tobias, Nicholas J., and Stinear, Timothy P.
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DISTRIBUTION (Probability theory) , *BURULI ulcer , *GENOTYPES , *SINGLE nucleotide polymorphisms , *MYCOBACTERIUM , *ANIMAL mechanics - Abstract
Efforts to control the spread of Buruli ulcer – an emerging ulcerative skin infection caused by Mycobacterium ulcerans - have been hampered by our poor understanding of reservoirs and transmission. To help address this issue, we compared whole genomes from 18 clinical M. ulcerans isolates from a 30km2 region within the Asante Akim North District, Ashanti region, Ghana, with 15 other M. ulcerans isolates from elsewhere in Ghana and the surrounding countries of Ivory Coast, Togo, Benin and Nigeria. Contrary to our expectations of finding minor DNA sequence variations among isolates representing a single M. ulcerans circulating genotype, we found instead two distinct genotypes. One genotype was closely related to isolates from neighbouring regions of Amansie West and Densu, consistent with the predicted local endemic clone, but the second genotype (separated by 138 single nucleotide polymorphisms [SNPs] from other Ghanaian strains) most closely matched M. ulcerans from Nigeria, suggesting another introduction of M. ulcerans to Ghana, perhaps from that country. Both the exotic genotype and the local Ghanaian genotype displayed highly restricted intra-strain genetic variation, with less than 50 SNP differences across a 5.2Mbp core genome within each genotype. Interestingly, there was no discernible spatial clustering of genotypes at the local village scale. Interviews revealed no obvious epidemiological links among BU patients who had been infected with identical M. ulcerans genotypes but lived in geographically separate villages. We conclude that M. ulcerans is spread widely across the region, with multiple genotypes present in any one area. These data give us new perspectives on the behaviour of possible reservoirs and subsequent transmission mechanisms of M. ulcerans. These observations also show for the first time that M. ulcerans can be mobilized, introduced to a new area and then spread within a population. Potential reservoirs of M. ulcerans thus might include humans, or perhaps M. ulcerans-infected animals such as livestock that move regularly between countries. Author Summary: In this study we use the power of whole genome sequence comparisons to track the spread of Mycobacterium ulcerans, the causative agent of Buruli ulcer, through several villages in the Ashanti region of Ghana, providing new insights on the behaviour of this enigmatic and emerging pathogen. [ABSTRACT FROM AUTHOR]
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- 2015
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10. Whole Genome Comparisons Suggest Random Distribution of Mycobacterium ulcerans Genotypes in a Buruli Ulcer Endemic Region of Ghana.
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Ablordey, Anthony S., Vandelannoote, Koen, Frimpong, Isaac A., Ahortor, Evans K., Amissah, Nana Ama, Eddyani, Miriam, Durnez, Lies, Portaels, Françoise, de Jong, Bouke C., Leirs, Herwig, Porter, Jessica L., Mangas, Kirstie M., Lam, Margaret M. C., Buultjens, Andrew, Seemann, Torsten, Tobias, Nicholas J., and Stinear, Timothy P.
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BURULI ulcer , *MYCOBACTERIUM , *ENDEMIC diseases , *GENOMES , *GENOTYPES - Abstract
Efforts to control the spread of Buruli ulcer – an emerging ulcerative skin infection caused by Mycobacterium ulcerans - have been hampered by our poor understanding of reservoirs and transmission. To help address this issue, we compared whole genomes from 18 clinical M. ulcerans isolates from a 30km2 region within the Asante Akim North District, Ashanti region, Ghana, with 15 other M. ulcerans isolates from elsewhere in Ghana and the surrounding countries of Ivory Coast, Togo, Benin and Nigeria. Contrary to our expectations of finding minor DNA sequence variations among isolates representing a single M. ulcerans circulating genotype, we found instead two distinct genotypes. One genotype was closely related to isolates from neighbouring regions of Amansie West and Densu, consistent with the predicted local endemic clone, but the second genotype (separated by 138 single nucleotide polymorphisms [SNPs] from other Ghanaian strains) most closely matched M. ulcerans from Nigeria, suggesting another introduction of M. ulcerans to Ghana, perhaps from that country. Both the exotic genotype and the local Ghanaian genotype displayed highly restricted intra-strain genetic variation, with less than 50 SNP differences across a 5.2Mbp core genome within each genotype. Interestingly, there was no discernible spatial clustering of genotypes at the local village scale. Interviews revealed no obvious epidemiological links among BU patients who had been infected with identical M. ulcerans genotypes but lived in geographically separate villages. We conclude that M. ulcerans is spread widely across the region, with multiple genotypes present in any one area. These data give us new perspectives on the behaviour of possible reservoirs and subsequent transmission mechanisms of M. ulcerans. These observations also show for the first time that M. ulcerans can be mobilized, introduced to a new area and then spread within a population. Potential reservoirs of M. ulcerans thus might include humans, or perhaps M. ulcerans-infected animals such as livestock that move regularly between countries. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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11. Insertion Sequence Element Single Nucleotide Polymorphism Typing Provides Insights into the Population Structure and Evolution of Mycobacterium ulcerans across Africa.
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Vandelannoote, Koen, Jordaens, Kurt, Bomans, Pieter, Leirs, Herwig, Durnez, Lies, Affolabi, Dissou, Sopoh, Ghislain, Aguiar, Julia, Maving Phanzu, Delphin, Kibadi, Kapay, Eyangoh, Sara, Bayonne Manou, Louis, Odame Phillips, Richard, Adjei, Ohene, Ablordey, Anthony, Rigouts, Leen, Portaels, Françoise, Eddyani, Miriam, and de Jong, Bouke C.
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SINGLE nucleotide polymorphisms , *BURULI ulcer , *PATHOGENIC microorganisms , *MYCOBACTERIUM , *DNA insertion elements , *PHYLOGEOGRAPHY - Abstract
Buruli ulcer is an indolent, slowly progressing necrotizing disease of the skin caused by infection with Mycobacterium ulcerans. In the present study, we applied a redesigned technique to a vast panel of M. ulcerans disease isolates and clinical samples originating from multiple African disease foci in order to (i) gain fundamental insights into the population structure and evolutionary history of the pathogen and (ii) disentangle the phylogeographic relationships within the genetically conserved cluster of African M. ulcerans. Our analyses identified 23 different African insertion sequence element single nucleotide polymorphism (ISE-SNP) types that dominate in different areas where Buruli ulcer is endemic. These ISE-SNP types appear to be the initial stages of clonal diversification from a common, possibly ancestral ISE-SNP type. ISE-SNP types were found unevenly distributed over the greater West African hydrological drainage basins. Our findings suggest that geographical barriers bordering the basins to some extent prevented bacterial gene flow between basins and that this resulted in independent focal transmission clusters associated with the hydrological drainage areas. Different phylogenetic methods yielded two well-supported sister clades within the African ISE-SNP types. The ISE-SNP types from the "pan-African clade" were found to be widespread throughout Africa, while the ISE-SNP types of the "Gabonese/Cameroonian clade" were much rarer and found in a more restricted area, which suggested that the latter clade evolved more recently. Additionally, the Gabonese/Cameroonian clade was found to form a strongly supported monophyletic group with Papua New Guinean ISE-SNP type 8, which is unrelated to other Southeast Asian ISE-SNP types. [ABSTRACT FROM AUTHOR]
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- 2014
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12. Burden of Mycobacterium ulcerans Disease (Buruli Ulcer) and the Underreporting Ratio in the Territory of Songololo, Democratic Republic of Congo.
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Mavinga Phanzu, Delphin, Suykerbuyk, Patrick, Saunderson, Paul, Ngwala Lukanu, Philippe, Masamba Minuku, Jean-Bedel, Imposo, Désiré Bofunga B., Mbadu Diengidi, Blanchard, Kayinua, Makanzu, Tamfum Muyembe, Jean-Jacques, Tshindele Lutumba, Pascal, de Jong, Bouke C., Portaels, Françoise, and Boelaert, Marleen
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BURULI ulcer , *MYCOBACTERIAL diseases , *MYCOBACTERIUM , *CONSCIOUSNESS raising , *NEGLECTED diseases , *BACTERIAL diseases - Abstract
Background: Cutaneous infection by Mycobacterium ulcerans, also known as Buruli ulcer (BU), represents the third most common mycobacterial disease in the world after tuberculosis and leprosy. Data on the burden of BU disease in the Democratic Republic of Congo are scanty. This study aimed to estimate the prevalence rate and the distribution of BU in the Songololo Territory, and to assess the coverage of the existing hospital-based reporting system. Methods: We conducted a cross-sectional survey (July–August 2008) using the door-to-door method simultaneously in the two rural health zones (RHZ) of the Songololo Territory (RHZ of Kimpese and Nsona-Mpangu), each containing twenty health areas. Cases were defined clinically as active BU and inactive BU in accordance with WHO-case definitions. Results: We detected 775 BU patients (259 active and 516 inactive) in a total population of 237,418 inhabitants. The overall prevalence of BU in Songololo Territory was 3.3/1000 inhabitants, varying from 0 to 27.5/1000 between health areas. Of the 259 patients with active BU, 18 (7%) had been reported in the hospital-based reporting system at Kimpese in the 6–8 months prior to the survey. Conclusion: The survey demonstrated a huge variation of prevalence between health areas in Songololo Territory and gross underreporting of BU cases in the hospital-based reporting system. Data obtained may contribute to better targeted and improved BU control interventions, and serve as a baseline for future assessments of the control program. Author Summary: Buruli ulcer (BU) is a necrotizing bacterial infection of skin, subcutaneous tissue and bone, caused by an environmental pathogen, Mycobacterium ulcerans. BU is considered as one of the Neglected Tropical Diseases with a poorly known global prevalence, and mainly affects remote rural African communities. Data on the burden of BU disease in the Democratic Republic of Congo (DRC) are scanty. The present study is the first exhaustive survey in DRC on the frequency of BU in the community. The survey demonstrated large variations in prevalence between health areas in Songololo Territory. Moreover, our data showed that the BU cases in the hospital-based reporting system reflect only the tip of the iceberg of the true active BU prevalence. Indeed, only one in thirteen active BU cases was notified at the hospital at Kimpese in the 6–8 months prior to the survey. The present data will serve as a baseline assessment for the evaluation of control interventions in the study area, and, more generally, this study aims to raise awareness about the issue of underdetection of BU and the importance of increasing access to diagnosis and care. As such, we hope the study will contribute to improved control of BU. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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13. Immunogenic Mycobacterium africanum Strains Associated with Ongoing Transmission in The Gambia.
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Gehre, Florian, Antonio, Martin, Otu, Jacob K., Sallah, Neneh, Secka, Oumie, Faal, Tutty, Owiafe, Patrick, Sutherland, Jayne S., Adetifa, Ifedayo M., Ota, Martin O., Kampmann, Beate, Corrah, Tumani, and de Jong, Bouke C.
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MYCOBACTERIUM tuberculosis , *MYCOBACTERIUM , *PATHOGENIC microorganisms , *TUBERCULOSIS research - Abstract
In West Africa, Mycobacterium tuberculosis strains co-circulate with M. africanum, and both pathogens cause pulmonary tuberculosis in humans. Given recent findings that M. tuberculosis T-cell epitopes are hyperconserved, we hypothesized that more immunogenic strains have increased capacity to spread within the human host population. We investigated the relationship between the composition of the mycobacterial population in The Gambia, as measured by spoligotype analysis, and the immunogenicity of these strains as measured by purified protein derivative-induced interferon-γ release in ELISPOT assays of peripheral blood mononuclear cells. We found a positive correlation between strains with superior spreading capacity and their relative immunogenicity. Although our observation is true for M. tuberculosis and M. africanum strains, the association was especially pronounced in 1 M. africanum sublineage, characterized by spoligotype shared international type 181, which is responsible for 20% of all tuberculosis cases in the region and therefore poses a major public health threat in The Gambia. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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14. The First Phylogeographic Population Structure and Analysis of Transmission Dynamics of M. africanum West African 1— Combining Molecular Data from Benin, Nigeria and Sierra Leone.
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Gehre, Florian, Antonio, Martin, Faïhun, Frank, Odoun, Mathieu, Uwizeye, Cecile, de Rijk, Pim, de Jong, Bouke C., and Affolabi, Dissou
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PHYLOGEOGRAPHY , *MYCOBACTERIUM , *TUBERCULOSIS , *GENOTYPE-environment interaction - Abstract
Mycobacterium africanum is an important cause of tuberculosis (TB) in West Africa. So far, two lineages called M. africanum West African 1 (MAF1) and M. africanum West African 2 (MAF2) have been defined. Although several molecular studies on MAF2 have been conducted to date, little is known about MAF1. As MAF1 is mainly present in countries around the Gulf of Guinea we aimed to estimate its prevalence in Cotonou, the biggest city in Benin. Between 2005–06 we collected strains in Cotonou/Benin and genotyped them using spoligo- and 12-loci-MIRU-VNTR-typing. Analyzing 194 isolates, we found that 31% and 6% were MAF1 and MAF2, respectively. Therefore Benin is one of the countries with the highest prevalence (37%) of M. africanum in general and MAF1 in particular. Moreover, we combined our data from Benin with publicly available genotyping information from Nigeria and Sierra Leone, and determined the phylogeographic population structure and genotypic clustering of MAF1. Within the MAF1 lineage, we identified an unexpected great genetic variability with the presence of at least 10 sub-lineages. Interestingly, 8 out of 10 of the discovered sub-lineages not only clustered genetically but also geographically. Besides showing a remarkable local restriction to certain regions in Benin and Nigeria, the sub-lineages differed dramatically in their capacity to transmit within the human host population. While identifying Benin as one of the countries with the highest overall prevalence of M. africanum, this study also contains the first detailed description of the transmission dynamics and phylogenetic composition of the MAF1 lineage. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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15. Deciphering the Growth Behaviour of Mycobacterium africanum.
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Gehre, Florian, Otu, Jacob, DeRiemer, Kathryn, de Sessions, Paola Florez, Hibberd, Martin L., Mulders, Wim, Corrah, Tumani, de Jong, Bouke C., and Antonio, Martin
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MYCOBACTERIA , *BURULI ulcer , *MYCOBACTERIUM avium paratuberculosis , *MYCOBACTERIUM tuberculosis , *BACTERIAL cell membranes , *MYCOBACTERIUM , *FRAMESHIFT mutation , *HIV infections - Abstract
Background: Human tuberculosis (TB) in West Africa is not only caused by M. tuberculosis but also by bacteria of the two lineages of M. africanum. For instance, in The Gambia, 40% of TB is due to infections with M. africanum West African 2. This bacterial lineage is associated with HIV infection, reduced ESAT-6 immunogenicity and slower progression to active disease. Although these characteristics suggest an attenuated phenotype of M. africanum, no underlying mechanism has been described. From the first descriptions of M. africanum in the literature in 1969, the time to a positive culture of M. africanum on solid medium was known to be longer than the time to a positive culture of M. tuberculosis. However, the delayed growth of M. africanum, which may correlate with the less virulent phenotype in the human host, has not previously been studied in detail. Methodology/Principal Findings: We compared the growth rates of M. tuberculosis and M. africanum isolates from The Gambia in two liquid culture systems. M. africanum grows significantly slower than M. tuberculosis, not only when grown directly from sputa, but also in growth experiments under defined laboratory conditions. We also sequenced four M. africanum isolates and compared their whole genomes with the published M. tuberculosis H37Rv genome. M. africanum strains have several non-synonymous SNPs or frameshift mutations in genes that were previously associated with growth-attenuation. M. africanum strains also have a higher mutation frequency in genes crucial for transport of sulphur, ions and lipids/fatty acids across the cell membrane into the bacterial cell. Surprisingly, 5 of 7 operons, recently described as essential for intracellular survival of H37Rv in the host macrophage, showed at least one non-synonymously mutated gene in M. africanum. Conclusions/Significance: The altered growth behaviour of M. africanum might indicate a different survival strategy within host cells. Author Summary: Mycobacterium tuberculosis and Mycobacterium africanum are the two major lineages within the M. tuberculosis complex that cause human tuberculosis in West Africa. Despite being closely related, the outcome after infection differs between these two pathogens. Although M. africanum has not yet been studied to the same extent as M. tuberculosis, M. africanum is less likely to stimulate the host immune system or to progress to active disease. We hypothesized that this somewhat attenuated phenotype is due to the slower growth of M. africanum within the host. Therefore, we analysed clinical isolates from 522 patients with tuberculosis in The Gambia. M. africanum West Africa 2 strains grew more slowly than M. tuberculosis. We sequenced four M. africanum strains and identified several candidate genes that may cause the growth-attenuation of the bacteria. Describing the fundamental genomic and phenotypic differences between M. tuberculosis and M. africanum will enable us to better understand the virulence mechanisms that make M. tuberculosis one of the most successful bacterial pathogens, and to discover potential strategies to interfere with mycobacterial pathogenicity. [ABSTRACT FROM AUTHOR]
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- 2013
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16. The Genome of Mycobacterium Africanum West African 2 Reveals a Lineage-Specific Locus and Genome Erosion Common to the M. tuberculosis Complex.
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Bentley, Stephen D., Comas, Iñaki, Bryant, Josephine M., Walker, Danielle, Smith, Noel H., Harris, Simon R., Thurston, Scott, Gagneux, Sebastien, Wood, Jonathan, Antonio, Martin, Quail, Michael A., Gehre, Florian, Adegbola, Richard A., Parkhill, Julian, and de Jong, Bouke C.
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MYCOBACTERIA , *TUBERCULOSIS , *GENETIC drift , *MYCOBACTERIUM tuberculosis , *MYCOBACTERIUM , *GENOMES , *CONTACT tracing - Abstract
Background: M. africanum West African 2 constitutes an ancient lineage of the M. tuberculosis complex that commonly causes human tuberculosis in West Africa and has an attenuated phenotype relative to M. tuberculosis. Methodology/Principal Findings: In search of candidate genes underlying these differences, the genome of M. africanum West African 2 was sequenced using classical capillary sequencing techniques. Our findings reveal a unique sequence, RD900, that was independently lost during the evolution of two important lineages within the complex: the "modern" M. tuberculosis group and the lineage leading to M. bovis. Closely related to M. bovis and other animal strains within the M. tuberculosis complex, M. africanum West African 2 shares an abundance of pseudogenes with M. bovis but also with M. africanum West African clade 1. Comparison with other strains of the M. tuberculosis complex revealed pseudogenes events in all the known lineages pointing toward ongoing genome erosion likely due to increased genetic drift and relaxed selection linked to serial transmission-bottlenecks and an intracellular lifestyle. Conclusions/Significance: The genomic differences identified between M. africanum West African 2 and the other strains of the Mycobacterium tuberculosis complex may explain its attenuated phenotype, and pave the way for targeted experiments to elucidate the phenotypic characteristic of M. africanum. Moreover, availability of the whole genome data allows for verification of conservation of targets used for the next generation of diagnostics and vaccines, in order to ensure similar efficacy in West Africa. Author Summary: Mycobacterium africanum, a close relative of M. tuberculosis, is studied for the following reasons: M. africanum is commonly isolated from West African patients with tuberculosis yet has not spread beyond this region, it is more common in HIV infected patients, and it is less likely to lead to tuberculosis after one is exposed to an infectious case. Understanding this organism's unique biology gets a boost from the decoding of its genome, reported in this issue. For example, genome analysis reveals that M. africanum contains a region shared with "ancient" lineages in the M. tuberculosis complex and other mycobacterial species, which was lost independently from both M. tuberculosis and M. bovis. This region encodes a protein involved in transmembrane transport. Furthermore, M. africanum has lost genes, including a known virulence gene and genes for vitamin synthesis, in addition to an intact copy of a gene that may increase its susceptibility to antibiotics that are insufficiently active against M. tuberculosis. Finally, the genome sequence and analysis reported here will aid in the development of new diagnostics and vaccines against tuberculosis, which need to take into account the differences between M. africanum and other species in order to be effective worldwide. [ABSTRACT FROM AUTHOR]
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- 2012
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17. Correction: Whole Genome Comparisons Suggest Random Distribution of Mycobacterium ulcerans Genotypes in a Buruli Ulcer Endemic Region of Ghana.
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Ablordey, Anthony S., Vandelannoote, Koen, Frimpong, Isaac A., Ahortor, Evans K., Amissah, Nana Ama, Eddyani, Miriam, Durnez, Lies, Portaels, Françoise, de Jong, Bouke C., Leirs, Herwig, Porter, Jessica L., Mangas, Kirstie M., Lam, Margaret M. C., Buultjens, Andrew, Seemann, Torsten, Tobias, Nicholas J., and Stinear, Timothy P.
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BURULI ulcer , *DISTRIBUTION (Probability theory) , *MYCOBACTERIUM , *GENOTYPES , *MYCOBACTERIA , *GENOMES - Abstract
This document is a correction notice for an article on the distribution of Mycobacterium ulcerans genotypes in a region of Ghana affected by Buruli ulcer. It corrects an error in Table 1 of the article, specifically in the "ENA" column. The corrected table is provided. The document also includes a list of individuals and their corresponding data, collected as part of a study, from various locations in Ghana and Cote d'Ivoire. Additionally, it provides a table of information about different strains of bacteria collected from various locations in Africa, including Nigeria, Democratic Republic of the Congo, and Ghana. This information can be valuable for researchers studying bacterial strains and their geographical distribution in Africa. [Extracted from the article]
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- 2015
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18. Correction: Whole Genome Comparisons Suggest Random Distribution of Mycobacterium ulcerans Genotypes in a Buruli Ulcer Endemic Region of Ghana.
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Ablordey, Anthony S., Vandelannoote, Koen, Frimpong, Isaac A., Ahortor, Evans K., Amissah, Nana Ama, Eddyani, Miriam, Durnez, Lies, Portaels, Françoise, de Jong, Bouke C., Leirs, Herwig, Porter, Jessica L., Mangas, Kirstie M., Lam, Margaret M. C., Buultjens, Andrew, Seemann, Torsten, Tobias, Nicholas J., and Stinear, Timothy P.
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MYCOBACTERIUM , *BURULI ulcer , *GENOMICS - Abstract
A correction to the article "Whole Genome Comparisons Suggest Random Distribution of Mycobacterium ulcerans Genotypes in a Buruli Ulcer Endemic Region of Ghana" that was published in the May 13, 2015 issue is presented.
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- 2015
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