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Tuberculosis (TB), an infectious airborne disease caused by Mycobacterium tuberculosis (Mtb), is a serious public health threat reported as the leading cause of morbidity and mortality worldwide. South Africa is a high-TB-burden country with TB being the highest infectious disease killer. This study investigated the distribution of Mtb mutations and spoligotypes in rural Eastern Cape Province. The Mtb isolates included were 1157 from DR-TB patients and analysed by LPA followed by spoligotyping of 441 isolates. The distribution of mutations and spoligotypes was done by spatial analysis. The rpoB gene had the highest number of mutations. The distribution of rpoB and katG mutations was more prevalent in four healthcare facilities, inhA mutations were more prevalent in three healthcare facilities, and heteroresistant isolates were more prevalent in five healthcare facilities. The Mtb was genetically diverse with Beijing more prevalent and largely distributed. Spatial analysis and mapping of gene mutations and spoligotypes revealed a better picture of distribution.

Study aim. Effective Tuberculosis (TB) control measures in Oman have reduced the annual incidence of tuberculosis cases by 92% between 1981 and 2016. However, the current incidence remains above the program control target of

Objectives: Evaluate the association between rifampicin resistance and the presence of at least one SNP in the rpoB and ponA1 genes and the spoligotype defined lineages. Material and Methods: This study analyzed two databases of 484 genomes of M. tuberculosis from strains isolated from patients in the cities of Lima and Callao, for which the odds ratio (OR) was calculated considering belonging to a certain spoligotype defined lineages as an exposure factor. Results: No statistically significant association (ρ value> 0.05) was found between the presence of at least one SNP in the rpoB gene and the lineages included in the study (LAM, Haarlem, T and Beijing). However, a statistically significant association was found between the presence of at least one SNP in the ponA1 gene and the LAM and Haarlem lineages (ρ value 0.05) entre la presencia de al menos un SNP en el gen rpoB y los linajes incluidos en el estudio (LAM, Haarlem, T y Beijing). No obstante, se halló una asociación estadísticamente significativa entre la presencia de al menos un SNP en el gen ponA1 y los linajes LAM y Haarlem (valor de ρ

Background There is a general dearth of information on extrapulmonary tuberculosis (EPTB). Here, we investigated Mycobacterium tuberculosis (Mtb) drug resistance and transmission patterns in EPTB patients treated in the Tshwane metropolitan area, in South Africa. Methods Consecutive Mtb culture-positive non-pulmonary samples from unique EPTB patients underwent mycobacterial genotyping and were assigned to phylogenetic lineages and transmission clusters based on spoligotypes. MTBDRplus assay was used to search mutations for isoniazid and rifampin resistance. Machine learning algorithms were used to identify clinically meaningful patterns in data. We computed odds ratio (OR), attributable risk (AR) and corresponding 95% confidence intervals (CI). Results Of the 70 isolates examined, the largest cluster comprised 25 (36%) Mtb strains that belonged to the East Asian lineage. East Asian lineage was significantly more likely to occur within chains of transmission when compared to the Euro-American and East-African Indian lineages: OR = 10.11 (95% CI: 1.56–116). Lymphadenitis, meningitis and cutaneous TB, were significantly more likely to be associated with drug resistance: OR = 12.69 (95% CI: 1.82–141.60) and AR = 0.25 (95% CI: 0.06–0.43) when compared with other EPTB sites, which suggests that poor rifampin penetration might be a contributing factor. Conclusions The majority of Mtb strains circulating in the Tshwane metropolis belongs to East Asian, Euro-American and East-African Indian lineages. Each of these are likely to be clustered, suggesting on-going EPTB transmission. Since 25% of the drug resistance was attributable to sanctuary EPTB sites notorious for poor rifampin penetration, we hypothesize that poor anti-tuberculosis drug dosing might have a role in the development of resistance.

Bovine tuberculosis (bTB) is an important zoonosis, which has been re-emerging in different ecological scenarios. In Sicily, Italy, from 2004 to 2014, an anatomopathological survey for tuberculosis-like lesions both in farmed and wild animals was performed. The isolates were genotyped using spoligotyping and Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) techniques. High prevalence of lesions was observed for cattle (4%), pigs (4.9%) and wild boars (6.8%), and a total of 625 Mycobacterium bovis isolates were identified. Genotyping analysis showed the presence of 37 different spoligotypes including fifteen spoligotypes not present in other Italian regions and 266 MIRU-VNTR profiles. Spoligotype SB0120 exhibited the highest prevalence in cattle (50%) and pigs (56%) and the highest genetic variety with 126 different MIRU-VNTR profiles. The isolation of M. bovis in a farmer underlines the importance of M. bovis identification during the human TB diagnostic processes. This study supported the use of the genotyping analysis as a valuable tool for the evaluation of the epidemiological role of pigs and other domestic reservoirs such as goats and the role of wildlife in the maintenance of bTB infection.

Objectives To determine genetic diversity by comparing the whole genome sequences of cattle and human Mycobacterium bovis isolates from Baja California. Methods A whole genome sequencing strategy was used to obtain the molecular fingerprints of 172 isolates of M. bovis obtained from Baja California, Mexico; 155 isolates were from cattle and 17 isolates were from humans. Spoligotypes were characterized in silico and single nucleotide polymorphism (SNP) differences between the isolates were evaluated. Results A total of 12 M. bovis spoligotype patterns were identified in cattle and humans. Two predominant spoligotypes patterns were seen in both cattle and humans: SB0145 and SB1040. The SB0145 spoligotype represented 59% of cattle isolates ( n =91) and 65% of human isolates ( n =11), while the SB1040 spoligotype represented 30% of cattle isolates ( n =47) and 30% of human isolates ( n =5). When evaluating SNP differences, the human isolates were intimately intertwined with the cattle isolates. Conclusions All isolates from humans had spoligotype patterns that matched those observed in the cattle isolates, and all human isolates shared common ancestors with cattle in Baja California based on SNP analysis. This suggests that most human tuberculosis caused by M. bovis in Baja California is derived from M. bovis circulating in Baja California cattle. These results reinforce the importance of bovine tuberculosis surveillance and control in this region.

The role of domestic pigs in the epidemiology of Mycobacterium tuberculosis complex (MTC) is considered to be limited due to the characteristics of intensive production systems. However, in southwestern Spain, Iberian pigs are usually raised under extensive management systems, sharing their habitat with other domestic and wild species, some of which may act as reservoirs of MTC. Our objective was to determine the seroprevalence, risk factors, spatial distribution and spoligotypes of MTC circulating in extensively farmed pigs in Andalusia (southern Spain), a region with a high prevalence of tuberculosis in both cattle and wild boar populations. Serum samples from 3622 extensively-raised Iberian pigs from 129 randomly selected farms were tested for antibodies against MTC using an indirect (P22) ELISA. Antibodies to MTC were detected in 82 pigs (2.3%; 95%CI: 1.8–2.8%). Seropositivity was significantly higher in sows (3.7%) than in fattening pigs (1.7%) (P = 0.0001). Herd prevalence was 24.8% (95%CI: 17.4–32.3%). Two risk factors were associated with MTC seropositivity on farms: herd size (higher seroprevalence on larger farms) (OR=1.001; 95%CI: 1.000–1.002), and the presence of neighboring goat flocks (OR = 7.345; 95%CI: 1.464–36.848). Two statistically significant spatial clusters (P < 0.001) were identified in the north-west of Andalusia. A total of 25 different MTC spoligotypes were isolated in pigs bred extensively in the study area. Based on the serological and molecular results obtained in the current study, it is possible that extensively raised Iberian pigs may act as an MTC reservoir in Mediterranean ecosystems. The high herd prevalence, as well as the identification of significant spatial clusters, indicates widespread, but not homogenous MTC circulation among extensively-managed pig farms. Risk-based surveillance and control programs should be implemented on this type of farms in Spain., The present work was partially funded by the Spanish Ministry of Economy and Competitiveness (MINECO) research grant Ref. AGL2013-49159-C2-2-R. D. Cano-Terriza holds a FPU pre-doctoral scholarship (FPU14/00842) funded by the Spanish Ministry of Education, Culture and Sport.

Tuberculosis has been diagnosed in wild boar (Sus scrofa) in several European countries during the last decade; however, almost no information has been reported to date for Portugal. This study aimed to investigate tuberculosis in wild boar in Portugal through characterization of Mycobacterium bovis infection and identification of disease risk factors. Tissue samples were obtained from hunted wild boar during the 2005 and 2006 hunting seasons. Samples were inspected for gross lesions and processed for culture. Acid-fast bacterial isolates were identified by polymerase chain reaction and spoligotyping. Associations between tuberculosis in wild boar and several variables linked to wild ungulate diversity and relative abundance, livestock density, and cattle tuberculosis incidence were investigated. Mycobacterium bovis isolates were identified in 18 of 162 wild boars from three of eight study areas. Infection rates ranged from 6% (95% confidence interval [CI(P95%)] = 1-21%) to 46% (CI(P95%) = 27-67%) in the three infected study areas; females in our sample were at greater risk of being infected than males (odds ratio = 4.33; CI(P95%) = 3.31-5.68). Spoligotyping grouped the M. bovis isolates in three clusters and one isolate was a novel spoligotype not previously reported in international databases. Detection of M. bovis was most consistently associated with variables linked to wild ungulate relative abundance, suggesting that these species, particularly the wild boar, might act as maintenance hosts in Portugal.

Background Although epidemiologic and socioeconomic criteria and biomedical risk factors indicate high-priority for tuberculosis (TB) control in Mexico, molecular epidemiology studies of the disease in the country are scarce. Methods Complete sociodemographic and clinical data were obtained from 248 of the 432 pulmonary TB (PTB) cases confirmed from 2006 to 2010 on the population under epidemiological surveillance in the state of San Luis Potosí, México. From most PTB cases with complete data Mycobacterium tuberculosis complex (MTC) isolates were recovered and their spoligotypes, lineages and families, geographic distribution and drug resistance determined. Results Pulmonary tuberculosis incidence ranged from 2.4 to 33.4 (cases per 100,000 inhabitants) in the six state sanitary jurisdictions that were grouped in regions of low (jurisdictions I-II-III), intermediate (jurisdictions IV-V) and high incidence (jurisdiction VI) with 6.2, 17.3 and 33.4 rates, respectively. Most patients were poor, 50-years-median-age males and housewives. Among the 237 MTC spoligotyped isolates, 232 corresponded to M. tuberculosis (104 spoligotypes in 24 clusters) and five to M. bovis. The predominant Euro-American lineage was distributed all over the state, the East-Asian lineage (Beijing family) in the capital city, the Indo-Oceanic (Manila family) in eastern localities, and M. bovis in rural localities. Conclusions In San Luis Potosí TB affects mainly poor male adults and is caused by M. tuberculosis and to a minor extent by M. bovis. There is great genotypic diversity among M. tuberculosis strains, the Euro-American lineage being much more prevalent than the Indo-Oceanic and East-Asian lineages. The frequency of resistant strains is relatively low and not associated to any particular lineage.

The objective of this study was to determine the molecular pattern of M. bovis isolates from cattle of Northern Mexico and its relationship with some risk factors. Isolates (n=60) were obtained from the states of Coahuila (COA, n=14), Tamaulipas (TAM, n=16), Nuevo Leon (NL, n=14) and Baja California and Durango (DUR, n=16). The risk factors studied were: system of production (Dairy and Beef), state, age, lesion type (localized and generalized), and type of presentation (caseous and calcified). Samples were analyzed at the Regional Laboratory of Monterrey NL, following a spoligotyping protocol. Twenty-five spoligotypes belonging to the M. bovis complex were identified. Eleven (18.3%) isolates presented a unique pattern, whereas 49 (81.7%) were grouped in 14 clusters. The largest clusters had 12 and 17 isolates. The average heterozygocities per state were 21.4% (NL), 15.6% (TAM), 15.6% COA) and 9.9% (DUR). The genetic distances of the isolates between states did not show differences (P > 0.05) when examined by Chi-square tests. The average genetic diversity (15.6%) was due to the variation of strains within subpopulations. In this study an 8.3% difference among states was obtained, which suggest the idea of a unique strain of M. bovis with many variants and that the genetic diversity found for M. bovis could be in part due to the movement of animals between regions. Statistical analysis did not show association (P > 0.05) between risk factors and strains of M. bovis.