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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]

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]

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]