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Abstract Background Identification of nontuberculous mycobacteria (NTM) based on phenotypic tests is time-consuming, labor-intensive, expensive and often provides erroneous or inconclusive results. In the molecular method referred to as PRA-hsp65, a fragment of the hsp65 gene is amplified by PCR and then analyzed by restriction digest; this rapid approach offers the promise of accurate, cost-effective species identification. The aim of this study was to determine whether species identification of NTM using PRA-hsp65 is sufficiently reliable to serve as the routine methodology in a reference laboratory. Results A total of 434 NTM isolates were obtained from 5019 cultures submitted to the Institute Adolpho Lutz, Sao Paulo Brazil, between January 2000 and January 2001. Species identification was performed for all isolates using conventional phenotypic methods and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing a 441 bp fragment of hsp65. Phenotypic evaluation and PRA-hsp65 were concordant for 321 (74%) isolates. These assignments were presumed to be correct. For the remaining 113 discordant isolates, definitive identification was based on sequencing a 441 bp fragment of hsp65. PRA-hsp65 identified 30 isolates with hsp65 alleles representing 13 previously unreported PRA-hsp65 patterns. Overall, species identification by PRA-hsp65 was significantly more accurate than by phenotype methods (392 (90.3%) vs. 338 (77.9%), respectively; p < .0001, Fisher's test). Among the 333 isolates representing the most common pathogenic species, PRA-hsp65 provided an incorrect result for only 1.2%. Conclusion PRA-hsp65 is a rapid and highly reliable method and deserves consideration by any clinical microbiology laboratory charged with performing species identification of NTM.

Purpose: To describe katG and inhA mutations, clinical characteristics, treatment outcomes and clustering of drug-resistant tuberculosis (TB) in the State of São Paulo, southeast Brazil., Methods: Mycobacterium tuberculosis isolates from patients diagnosed with drug-resistant TB were screened for mutations in katG and inhA genes by line probe assay and Sanger sequencing, and typed by IS6110-restriction fragment-length polymorphism for clustering assessment. Clinical, epidemiological and demographic data were obtained from surveillance information systems for TB., Results: Among the 298 isolates studied, 127 (42.6%) were isoniazid-monoresistant, 36 (12.1%) polydrug-resistant, 93 (31.2%) MDR, 16 (5.4%) pre-extensively drug-resistant (pre-XDR), 9 (3%) extensively drug-resistant (XDR) and 17 (5.7%) susceptible after isoniazid retesting. The frequency of katG 315 mutations alone was higher in MDR isolates, while inhA promoter mutations alone were more common in isoniazid-monoresistant isolates. Twenty-six isolates phenotypically resistant to isoniazid had no mutations either in katG or inhA genes. The isolates with inhA mutations were found more frequently in clusters (75%) when compared to the isolates with katG 315 mutations (59.8%, p = 0.04). In our population, being 35-64 years old, presenting MDR-, pre-XDR- or XDR-TB and being a retreatment case were associated with unfavourable TB treatment outcomes., Conclusion: We found that katG and inhA mutations were not equally distributed between isoniazid-monoresistant and MDR isolates. In our population, clustering was higher for isolates with inhA mutations. Finally, unfavourable TB outcomes were associated with specific factors., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: We aimed to evaluate the costs of GenoType® MTBDRplus and MTBDRsl incurred during the diagnosis of first- and second-line drug-resistant tuberculosis (TB) in São Paulo, Brazil., Methods: Mean and activity-based costs of GenoType® were calculated in a referral laboratory for TB in Brazil., Results: The mean cost value and activity-based cost of GenoType® MTBDRplus were USD 19.78 and USD 35.80 and those of MTBDRsl were USD 54.25 and USD 41.85, respectively., Conclusions: The cost of GenoType® MTBDRplus was reduced owing to the high number of examinations performed and work optimization.

We assessed the performance of MTBDRsl for detection of resistance to fluoroquinolones, aminoglycosides/cyclic peptides, and ethambutol compared to BACTEC MGIT 960 by subjecting simultaneously to both tests 385 phenotypically multidrug-resistant-Mycobacterium tuberculosis isolates from Sao Paulo, Brazil. Discordances were resolved by Sanger sequencing. MTBDRsl correctly detected 99.7% of the multidrug-resistant isolates, 87.8% of the pre-XDR, and 73.9% of the XDR. The assay showed sensitivity of 86.4%, 100%, 85.2% and 76.4% for fluoroquinolones, amikacin/kanamycin, capreomycin and ethambutol, respectively. Specificity was 100% for fluoroquinolones and aminoglycosides/cyclic peptides, and 93.6% for ethambutol. Most fluoroquinolone-discordances were due to mutations in genome regions not targeted by the MTBDRsl v. 1.0: gyrA&#95;H70R and gyrB&#95;R446C, D461N, D449V, and N488D. Capreomycin-resistant isolates with wild-type rrs results on MTBDRsl presented tlyA mutations. MTBDRsl presented good performance for detecting resistance to second-line drugs and ethambutol in clinical isolates. In our setting, multidrug-resistant. isolates presented mutations not targeted by the molecular assay., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The World Health Organization advocates that sputum specimens submitted to tuberculosis (TB) diagnostic should be processed within 48 h after collection and be stored under cooling. We aimed to assess the performance of OMNIgene • SPUTUM reagent in maintaining viable specimens of Mycobacterium tuberculosis complex (MTBC) during transportation of sputum samples without refrigeration, in comparison to the standard protocol of the National TB Control Program. Sputum samples obtained in southeastern Brazil (June 2017 to July 2018) from 100 sequential patients with positive acid-fast bacillus smear microscopy were divided into two portions. Portion 1 continued to be cooled (standard protocol, STA), but portion 2 was added to OMNIgene • SPUTUM reagent (alternative protocol, OMS) until concomitant further processing. Both portions of all samples were cultured using MGIT and tested by Xpert MTB/RIF assay. Growth of MTBC in the first 42 days was detected in 96% of the cultures under the STA and 88% under the OMS. Intervals between processing and detecting MTBC growth in the two portions significantly differed (p = 0.0001). Portions under the two protocols showed similar results in the MTBC detection by Xpert assay and culture contamination by non-MTBC. The OMNIgene reagent liquefies and decontaminates sputum leading to a decrease in processing time. Although there was a small delay in mycobacterial growth, the OMNIgene reagent can be useful in specimens transported from collection sites over a long distance to centralized testing centers, maintaining viable MTBC for at least 8 days at room temperature., (© 2021. Sociedade Brasileira de Microbiologia.)

We analysed mutations in katG, inhA and rpoB genes, and isoniazid phenotypic resistance levels in Mycobacterium tuberculosis isolates from drug-resistant TB patients from São Paulo state, Brazil. Isolates resistant to the critical concentration of isoniazid in MGIT (0.1 µg/mL) were screened for mutations in katG 315 codon, inhA promoter region and rpoB RRDR by MTBDRplus assay and subjected to determination of isoniazid resistance levels by MGIT 960. Discordances were resolved by Sanger sequencing. Among the 203 isolates studied, 109 (54%) were isoniazid-monoresistant, 47 (23%) MDR, 29 (14%) polydrug-resistant, 12 (6%) pre-XDR and 6 (3%) XDR. MTBDRplus detected isoniazid mutations in 75% (153/203) of the isolates. Sequencing of the entire katG and inhA genes revealed mutations in 18/50 wild-type isolates by MTBDRplus (10 with novel mutations), resulting in a total of 32/203 (16%) isolates with no mutations detected. 81/83 (98%) isolates with katG 315 mutations alone had intermediate resistance. Of the 66 isolates with inhA C-15T mutation alone, 51 (77%) showed low-level, 14 (21%) intermediate and 1 (2%) high-level resistance. 5/6 (83%) isolates with mutations in both katG and inhA had high-level resistance. Inferred mutations corresponded to 22% (16/73) of all mutations found in rpoB. Mutations detected in katG regions other than codon 315 in this study might be potential new isoniazid resistance markers and could explain phenotypic resistance in some isolates without katG and inhA classic mutations. In our setting, 16% of isoniazid-resistant isolates, some with high-level resistance, presented no mutations either in katG or inhA., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Molecular-typing can help in unraveling epidemiological scenarios and improvement for disease control strategies. A literature review of Mycobacterium tuberculosis transmission in Brazil through genotyping on 56 studies published from 1996-2019 was performed. The clustering rate for mycobacterial interspersed repetitive units - variable tandem repeats (MIRU-VNTR) of 1,613 isolates were: 73%, 33% and 28% based on 12, 15 and 24-loci, respectively; while for RFLP-IS6110 were: 84% among prison population in Rio de Janeiro, 69% among multidrug-resistant isolates in Rio Grande do Sul, and 56.2% in general population in São Paulo. These findings could improve tuberculosis (TB) surveillance and set up a solid basis to build a database of Mycobacterium genomes.

Background: Since the implementation of the Xpert MTB/RIF in Sao Paulo, Brazil, numerous Mycobacterium tuberculosis isolates presenting "rifampicin-resistant genotype with rifampicin-susceptible phenotype" were observed., Objective: To evaluate the prevalence, rpoB mutations and transmission of M. tuberculosis resistant to rifampicin on Xpert MTB/RIF but susceptible on BACTEC MGIT system, in Sao Paulo state., Methods: Patients' isolates with this pattern of rifampicin discordance, collected from 2014 to 2017, had their rpoB predominant rifampicin-resistance-determining region sequenced and were genotyped by IS6110 restriction fragment-length polymorphism., Findings: The prevalence of rifampicin-discordant M. tuberculosis with genotypic resistance was 55.1% (156/283). Among the sequenced and genotyped isolates, 75.5% (111/147) were in clusters, largely associated with the type of rpoB mutation. Most isolates (98.6%; 72/73) harbouring the predominant mutation, His445Asn, were pooled into the two largest clusters, SP2ga (42/72; 58.3%) and SP5o (12/72; 16.7%). Ranking second, isolates carrying the silent mutation Phe433Phe were mostly (92.3%; 24/26) gathered into four groups of the family SP25., Conclusion: These findings suggest that this unusual high rifampicin discrepancy proportion was greatly influenced by few actively circulating clusters. Further studies on many of the rpoB mutations identified in our setting are needed to elucidate their association with phenotypic rifampicin resistance., (Copyright © 2020. Published by Elsevier Ltd.)

Introduction: We aimed to estimate the prevalence and transmission of drug-resistant tuberculosis in a high-burden Brazilian setting under directly observed therapy short-course strategy., Methods: Isolates of culture-confirmed pulmonary tuberculosis patients from Guarulhos, Brazil, diagnosed in October 2007-2011 were subjected to drug susceptibility and IS6110-restriction fragment length polymorphism testing., Results: The overall resistance prevalence was 11.5% and the multi-drug resistance rate was 4.2%. Twenty-six (43.3%) of 60 drug-resistant isolates were clustered. Epidemiological relationships were identified in 11 (42.3%) patients; 30.8% of the cases were transmitted in households., Conclusions: Drug-resistant tuberculosis was relatively low and transmitted in households and the community.

BACKGROUND Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis, and the number of new cases of multidrug resistant TB (MDR-TB), pre extensively drug-resistant TB (pre-XDR-TB) and extensively drug-resistant TB (XDR-TB) has increased considerably worldwide. OBJECTIVES Herein, using 156 M. tuberculosis isolates from 106 patients previously classified as MDR or pre-XDR or XDR isolates, we investigated the genetic mutation profiles associated with phenotypic resistances in patients with MDR-TB, pre-XDR-TB and XDR-TB, treatment outcomes and resistance evolution. METHODS Molecular analyses were performed by partial sequencing of the rpoB, katG, gyrA, gyrB, rrs genes and analysis of the fabG-inhA promoter region. Clinical, epidemiologic and demographic data were obtained from the TB Notification database system of São Paulo (TB-WEB) and the Information System for Special Tuberculosis Treatments (SITE-TB). FINDINGS Drug resistance was attributed to previously known mutations and a novel Asp449Val mutation in gyrB was observed in four isolates from the same patient. Ten patients had more than one isolate evaluated and eight of these patients displayed resistance progression. MAIN CONCLUSIONS The present study is the first to report the frequency of mutations related to second-line drug resistance in MDR-TB, pre-XDR-TB and XDR-TB isolates. The results could lead to the improvement of available technologies for the rapid detection of drug resistant TB.

Objective: Pulmonary nontuberculous mycobacterial infections are caused by nontuberculous mycobacteria (NTM), the microbiological diagnosis of which involves the isolation and identification of the same species in at least two sputum samples, one BAL fluid sample, or one lung biopsy sample. The objective of the present study was to determine the frequency at which the various NTM species are identified among selected individuals and in potential cases of pulmonary nontuberculous mycobacterial infection., Methods: This was a retrospective analysis of the data on species isolated from respiratory specimens collected from 2,843 individuals between 2011 and 2014. Potential NTM infection cases were identified on the basis of the international microbiological criteria adopted in the state of São Paulo., Results: A total of 50 species were identified using the molecular method PCR-restriction enzyme analysis. Samples collected from 1,014 individuals were analyzed in relation to the microbiological criteria, and 448 (44.18%) had a presumptive diagnosis of pulmonary nontuberculous mycobacterial infection, the species identified most frequently being, in descending order, Mycobacterium kansasii, M. abscessus, M. intracellulare, M. avium, and M. szulgai., Conclusions: Although various NTM species were identified among the individuals studied, those presumptively identified most frequently on the basis of the microbiological criteria adopted in the state of São Paulo were the ones that are most commonly associated with pulmonary nontuberculous mycobacterial infection worldwide or in specific geographic regions.

Objective: To evaluate the rapid diagnosis of multidrug-resistant tuberculosis, by using a commercial line probe assay for rifampicin and isoniazid detection (LPA-plus), in the routine workflow of a tuberculosis reference laboratory., Methods: The LPA-plus was prospectively evaluated on 341 isolates concurrently submitted to the automated liquid drug susceptibility testing system., Results: Among 303 phenotypically valid results, none was genotypically rifampicin false-susceptible (13/13; 100% sensitivity). Two rifampicin-susceptible isolates harboured rpoB mutations (288/290; 99.3% specificity) which, however, were non-resistance-conferring mutations. LPA-plus missed three isoniazid-resistant isolates (23/26; 88.5% sensitivity) and detected all isoniazid-susceptible isolates (277/277; 100% specificity). Among the 38 (11%) invalid phenotypic results, LPA-plus identified 31 rifampicin- and isoniazid-susceptible isolates, one isoniazid-resistant and six as non-Mycobacterium tuberculosis complex., Conclusions: LPA-plus showed excellent agreement (≥91%) and accuracy (≥99%). Implementing LPA-plus in our setting can speed up the diagnosis of multidrug-resistant tuberculosis, yield a significantly higher number of valid results than phenotypic drug susceptibility testing and provide further information on the drug-resistance level.

We evaluated the microscopic and macroscopic characteristics of mycobacteria growth indicator tube (MGIT) cultures for the presumptive identification of the Mycobacterium tuberculosis complex (MTBC) and assessed the reliability of this strategy for correctly directing isolates to drug susceptibility testing (DST) or species identification. A total of 1526 isolates of mycobacteria received at the Instituto Adolfo Lutz were prospectively subjected to presumptive identification by the observation of growth characteristics along with cord formation detection via microscopy. The presumptive identification showed a sensitivity, specificity and accuracy of 98.8, 92.5 and 97.9 %, respectively. Macroscopic analysis of MTBC isolates that would have been erroneously classified as non-tuberculous mycobacteria based solely on microscopic morphology enabled us to direct them rapidly to DST, representing a substantial gain to patients. In conclusion, the growth characteristics of mycobacteria in MGIT, when considered along with cord formation, increased the reliability of the presumptive identification, which has a great impact on the laboratory budget and turnaround times.

Accurate identification of Mycobacterium tuberculosis complex (MTBC) isolates is essential for tuberculosis (TB) control, especially in a high-burden country such as Brazil. Conventional identification methods are laborious and time-consuming, while rapid molecular methods are expensive and require skilled personnel and appropriate physical laboratory infrastructure. Immunochromatographic assays (ICAs) have been shown to provide a rapid and reliable TB diagnosis at a low cost. The use of the SD Bioline TB Ag MPT64 ICA (MPT64 assay) for rapid identification of MTBC clinical isolates in the routine diagnosis of a large-volume reference TB laboratory was evaluated. We analysed 375 isolates on solid and liquid media concurrently with conventional phenotypic methods, the PRA- hsp 65 molecular technique and the MPT64 assay. The sensitivity, specificity and accuracy of the ICA were 97.7, 100 and 98.1 %, respectively. The MPT64 assay yielded rapid and accurate results, enabling the treatment to be initiated early and also impacting on TB control.

Background: Little is known about the impact of growing migration on the pattern of tuberculosis (TB) transmission in middle-income countries. We estimated TB recent transmission and its associated factors and investigated the presence of cross-transmission between South American migrants and Brazilians., Methods: We studied a convenient sample of cases of people with pulmonary TB in a central area of São Paulo, Brazil, diagnosed between 2013 and 2014. Cases with similar restriction fragment length polymorphism (IS6110-RFLP) patterns of their Mycobacterium tuberculosis complex isolates were grouped in clusters (recent transmission). Clusters with both Brazilian and South American migrants were considered mixed (cross-transmission). Risk factors for recent transmission were studied using logistic regression., Results: Isolates from 347 cases were included, 76.7% from Brazilians and 23.3% from South American migrants. Fifty clusters were identified, which included 43% South American migrants and 60.2% Brazilians (odds ratio = 0.50, 95% confidence interval = 0.30-0.83). Twelve cross-transmission clusters were identified, involving 24.6% of all clustered cases and 13.8% of all genotyped cases, with migrants accounting for either an equal part or fewer cases in 11/12 mixed clusters., Conclusions: Our results suggest that TB disease following recent transmission is more common among Brazilians, especially among those belonging to high-risk groups, such as drug users. Cross-transmission between migrants and Brazilians was present, but we found limited contributions from migrants to Brazilians in central areas of São Paulo and vice versa.

We conducted a population-based study of tuberculosis (TB) from 2009 to 2015 in an indigenous community of Brazil, the largest in the country, to investigate risk factors associated with recent TB transmission. The clinical isolates of Mycobacterium tuberculosis were genotyped by IS 6110 -RFLP (restriction fragment length polymorphism) and spoligotyping analysis. Among 67 isolates typed by RFLP, 69% fell into fifteen clusters, and 91% of TB cases with shared IS 6110 -RFLP pattern were diagnosed within 2 years of another case in the cluster. Individual risk factors associated with genetic clustering were domestic overcrowding (odds ratio [OR]: 6.10; 95% confidence interval [CI]: 1.50-24.88) and low social class (OR: 3.72; 95% CI: 1.00-13.98). Most reported contacts (76%) were identified within the household of the index TB case, but most of the genetic clustering of M. tuberculosis occurred outside of household (79%). Expanded contacts investigation and prophylaxis outside of household should be considered as a priority for TB control programs in this population.

Background: The nontuberculous mycobacteria (NTM) are widely spread. In Brazil, 2,520 cases of rapidly growing mycobacteria (RGM) infections after medical procedures were reported, with 5.4% of cases related to nonsurgical invasive procedures and with an occurrence of 1 clone (BRA100) of Mycobacterium abscessus subsp bolletii., Objective: To describe a pseudooutbreak of M abscessus subsp bolletii in an endoscopy and bronchoscopy unit., Methods: The alert for a pseudooutbreak was given when 3 patients, in the same week, had a positive bronchoalveolar lavage culture for M abscessus subsp bolletii. The patients had no symptoms/signs of mycobacterial infection; thus, contamination of bronchoscopes was suspected. Samples for culturing were collected from bronchoscopes, digestive endoscopes, automated disinfection machines, and the water supply. Clinical samples were identified by polymerase chain reaction restriction-enzyme analysis (PRA) of the hsp65 gene and their pulsed-field gel electrophoresis pattern was compared with environmental samples., Results: The investigation demonstrated a contamination of bronchoscopes, digestive endoscopes, and disinfection machines. Molecular typing demonstrated that all strains belonged to the same clone (MAB01), identical to clone BRA100., Discussion: Cross-transmission due to poor disinfection as well as resistance to glutaraldehyde may play roles in the spread of MAB01 M abscessus subsp bolletii, which may have a unique resistance to the environment and adaption to human hosts. However the water supply may have played a role. Attention is needed to ensure the quality of water used to rinse disinfected equipment., (Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Mycobacterium abscessus group has heterogeneous susceptibility pattern among species. The species is most common cause of nosocomial infections. Macrolides minimum Inhibitory concentration (MIC) determination is essential for the treatment., Methods: Thirty-six strains were randomly selected for performing Resazurin Microtiter Assay (REMA) for clarithromycin testing in comparison to MIC test according to Clinical and Laboratory Standards Institute (2011) recommendation. REMA has been used for detection of drug resistance in M. tuberculosis. Extended incubation was performed to detect induced resistance., Results: Thirty microliters of resazurin (0.01%) was added after visually taking MIC reading. Resistance was observed in 11.1% of M. bolletti and 4.8% of M. abscessus strains; and induced resistance was detected in 77.8% and 95.2% of M. bolletti and M. abscessus strains, respectively. All strains of M. massiliense were susceptible. The samples presented same MIC value both by visual reading and through resazurin., Conclusion: The present study showed 100% concordance between both readings, with REMA providing easier to read and report results benefit. This change in reading can also reflect on the MIC determination and report, improving the test., (© 2016 Wiley Periodicals, Inc.)

Background: Detection of drug-resistant tuberculosis is essential for the control of the disease but it is often hampered by the limitation of transport and storage of samples from remote locations to the reference laboratory. We performed a retrospective field study to evaluate the performance of four supports enabling the transport and storage of samples to be used for molecular detection of drug resistance using the GenoType MTBDRplus., Methods: Two hundred Mycobacterium tuberculosis strains were selected and spotted on slides, FTA cards, GenoCards, and in ethanol. GenoType MTBDRplus was subsequently performed with the DNA extracted from these supports. Sensitivity and specificity were calculated and compared to the results obtained by drug susceptibility testing., Results: For all supports, the overall sensitivity and specificity for detection of resistance to RIF was between 95% and 100%, and for INH between 95% and 98%., Conclusion: The four transport and storage supports showed a good sensitivity and specificity for the detection of resistance to RIF and INH in M. tuberculosis strains using the GenoType MTBDRplus. These supports can be maintained at room temperature and could represent an important alternative cost-effective method useful for rapid molecular detection of drug-resistant TB in low-resource settings.

Tuberculosis (TB) is an infectious disease of global distribution, constituting a serious public health problem in Brazil. São Paulo State, located in the south-east of Brazil, notified 16,580 new TB cases in 2013. The Instituto Adolfo Lutz is a public health reference laboratory for TB diagnosis for all the State. Considering that rapid and accurate diagnosis is essential for TB control, the aim of this study was to evaluate the use of an in-house real-time (RT)-PCR assay targeting the mpt64 gene in the routine diagnosis of TB, and to compare this technique with smear microscopy and culture. From August 2012 to October 2013, 715 sputum samples from 657 patients were included in the study. Smear microscopy, culture, phenotypic and PRA-hsp65 identification of mycobacteria, and mpt64 RT-PCR were performed. With respect to confirmed TB cases (n = 62/657; 9.4%), smear microscopy had a sensitivity of 82.3%. Culture and RT-PCR showed the same sensitivity, i.e. 90.3%. Specificity was 99.7, 99.4 and 98.6% for smear microscopy, culture and RT-PCR, respectively. mpt64 RT-PCR showed high sensitivity and specificity for the detection of Mycobacterium tuberculosis complex in sputum samples. This technique can be deployed in laboratories that do not have a rapid test for TB available, enabling the performance of TB diagnosis in up to 5 h.

Introduction: The success of the Mycobacterium tuberculosis Beijing (MtbB) lineage in different geographical regions has been attributed to high transmission, increased virulence, drug resistance and rapid adaptation to the host. In some countries of secondary MtbB dispersion like South Africa and Peru, rising prevalence of the Beijing strains is registered. However, in neighboring countries to affected regions such as Mozambique and Brazil, respectively, the prevalence of these strains is still low and this could be due to biological particularities of the circulating MtbB strains and/or differentiated host susceptibility., Objective: To characterize genetically and phenotypically MtbB strains isolated in Brazil (n = 8) and Mozambique (n = 17)., Methods: This is a descriptive study of genotypes of the MtbB isolates, determined by spoligotyping, MIRU-VNTR typing, analysis of the IS6110 copy number in the NTF region and screening for mutations in mutT2, mutT4, rpoB, katG and pks 15/1 genes. Virulence-associated properties of the studied isolates were verified in the in vitro model of infection of human THP-1 cells., Results: The genotypes defined by the 24VNTRs were distinct for all isolates included in this study and presented an HGDI of 0.997. The VNTR patterns with seven copies of MIRU26 and seven copies of QUB26, representative for the previously described MtbB genotype B0, dominant in Russia, were detected in 38.5% of the studied isolates. In addition, all isolates presented RD105 deletion and a 7 bp insertion in pks15/1 gene. Almost all tested strains belonged to the RD181 sublineage, with the exception of two strains from Mozambique of RD150 sublineage. Combined analysis of the NTF region integrity and mutations in mutT genes showed that 62.5% and 47% of isolates obtained in Brazil and Mozambique, respectively, were of the ancestral genotype. The virulence index of the ancient isolates, evaluated in the THP-1 cells, was significantly lower than that of the modern genotype group., Conclusions: These data demonstrate genotype particularities of the Beijing strains isolated in Brazil and Mozambique, two countries of low prevalence of the MtbB lineage in local Mtb populations. In contrast to the neighboring countries with high prevalence of the MtbB strains of modern sublineage, significant proportions of the isolates obtained in Brazil and Mozambique were presented by the strains of the ancient sublineage. Our data suggest that lower virulence of the ancient strains, compared with the modern strains, could be involved in the slow spread of the MtbB strains in some regions., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We conducted a population-based study of tuberculosis (TB) cases in Dourados, Brazil, to assess the relationship between incarceration and TB in the general population. Incarceration was associated with TB in an urban population; 54% of Mycobacterium tuberculosis strains were related to strains from persons in prisons. TB control in prisons is critical for reducing disease prevalence.