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1.
Recent reports have suggested a change of Mycobacterium tuberculosis complex genetic diversity in Western Europe due to an increasing proportion of imported cases of tuberculosis (TB). This study analyzed a total of 705 M. tuberculosis strains isolated from 2006 to 2009 in Veneto, a North-Eastern Italian region, to see the impact of foreign-born cases vs. Italian patients on prevailing TB epidemiology. Strains were genotyped using spoligotyping followed by comparison with international genotyping database SITVIT2. Six spoligotyping clusters with suspected phylogeographical specificity for imported cases, were typed by 15-loci MIRUs for a finer characterization. Overall, 410 (58.16%) strains were isolated from foreign-born patients, while 295 (41.84%) were isolated from Italian patients. Older patients (>70 years, i.e., 46.4% of cases) predominated among Italians while younger age groups prevailed among foreign-born patients. Our results suggest that despite a high proportion of reactivation of latent TB infection in elderly Italian-born patients, active TB transmission between foreign-born and Italian patients may be ongoing, and argue in favor of an increased TB surveillance among immigrants to combat TB epidemic in Italy.  相似文献   

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Tuberculosis (TB) is still a serious public health problem, continuing to be an important threat for confined populations. We used spoligotyping to estimate the genotypic clades of Mycobacterium tuberculosis isolates from inmates in two blocks in a southeastern Brazilian prison unit, with TB incidence rate of 8185/100.000. The Latin American Mediterranean (LAM) clade is well represented in the country, and the LAM specific molecular markers, RDRio large sequence polymorphism and the SNP on the Rv3062 [ligB1212], were used to characterize spoligotype signatures from prison isolates. Typing of RDRio and ligB increase LAM clade from 66.7% (n = 72/108) to 69.4% (n = 75). The LAM2 SIT17 (n = 23) and SIT179 (n = 12) signatures comprised one third of all isolates, followed by Haarlem (11.5%, n = 12), T (8.7%, n = 9) and X (5.7%, n = 6) clades. Strains with unknown signatures represented 5.5% (n = 6), and four (3.7%) did not match any lineage. We observed RDRio among 64 (59.2%) isolates, and 54 (50%) were of the LAM clade. In particular, the LAM2/RDRio sub-lineage was significantly associated with clustering (p = 0.02) and its frequency was higher (32%) when compared to that of the previous general TB cases in RJ (4.29%). Overall cluster frequency defined by spoligotyping/IS6110-RFLP was 62%. The two evolutionary markers helped to evaluate some LAM signature misconceptions and demonstrate that LAM2/RDRio was found with high frequency, hitherto being unnoticed. All these data, allied to high clustering, imply that public health measures to minimize the escalation of TB in prison is essential, and both spoligotyping as well as RDRio would be useful tools to monitor the effects of the measures with respect to M. tuberculosis lineage variation.  相似文献   

4.
Tuberculosis (TB) continues to be a major health problem in India, and there is very little information about the prevalent genotypes of tubercle bacilli that cause TB in India, especially in Kerala. Our aim was to study the different circulating strains of Mycobacterium tuberculosis (MTB) that are prevalent in Kerala, India. We analyzed 168 MTB isolates from as many pulmonary TB patients using IS6110-RFLP, spoligotyping and MIRU-VNTRs. The results of IS6110-RFLP revealed that majority of isolates had null copy (10.89%) or single copy (44.87%) of IS6110 insertion. Low copy (<6) isolates accounted for 71.5% in the isolates studied. Genotypic clade designations were done by comparing with the SITVIT2 database which showed 68 patterns; of which 51 corresponded to different shared types whereas 17 patterns were orphans. Among the 51 SITs recorded, 42 SITs matched a preexisting SIT in the SITVIT2 database, whereas 9 SITs were newly-created. Majority of the isolates (64.28%) belonged to the ancestral East-African Indian (EAI) lineage. MIRU-40 and 31 (HGDI = 0.6555 and 0.6524) showed highest discrimination, while MIRU-2 and 20 (HGDI = 0.0354 and 0.0696) had the least discriminatory power. ETR-A and B (HGDI 0.7382 and 0.6743) discriminated better as compared to other MIRU loci. The overall HGDI for MIRU-VNTRs at 0.9735 (calculated for 166 isolates) showed a better discriminatory power than spoligotyping used alone. This study of MTB genotypic diversity was useful by providing a first snapshot of circulating MTB genotypic clones in Kerala.  相似文献   

5.
Tuberculosis is a major health problem in Portugal. To begin characterizing the population structure of Mycobacterium tuberculosis, spoligotyping was used for the systematic typing, through consecutive sampling, of patient isolates from the Amadora-Sintra area of Greater Lisbon. Distribution amongst major spoligotype families, including the Latin American Mediterranean (LAM), T, Haarlem and Beijing, was compared to that of the international spoligotype database SpolDB4 and to the European countries of traditional Portuguese immigration represented in SpolDB4. Spoligotypes from 665 isolates were analyzed and 97 shared international types (SITs) identified. In SpolDB4 Portugal is represented by part of the spoligotypes from this study explaining the reduced number of unidentified patterns. The importance of the LAM family, and especially of LAM1 and LAM9 sub-families that alone represented 38% of all the isolates in this study as compared to 8% relative to the European sub group, led us to believe that at least in this respect the population structure was closer to that of Africa and South America than to Europe. Spoligotypes characteristic of Portugal or Portuguese related settings were identified. These included SIT244 a T1 sub-family predominant in Portugal and Bangladesh, SIT64 a LAM 6 sub-family common to Portugal and Brazil, and SIT1106 a LAM 9 sub-family. These studies were the first in Portugal stressing the importance of monitoring the population structure of M. tuberculosis isolates, an important step towards gaining an understanding of tuberculosis and the dynamics of this disease.  相似文献   

6.
Bolivia ranks among the 10 Latin American countries with the highest rates of tuberculosis (TB) and multidrug resistant (MDR) TB. In view of this, and of the lacking information on the population structure of Mycobacterium tuberculosis in the country, we explored genotype associations with drug resistance and clustering by analyzing isolates collected in 2010 from 100 consecutive TB patients at risk of drug resistance in seven of the nine departments in which Bolivia is divided. Fourteen isolates were MDR, 29 had other drug resistance profiles, and 57 were pansusceptible. Spoligotype family distribution was: Haarlem 39.4%, LAM 26.3%, T 22.2%, S 2.0%, X 1.0%, orphan 9.1%, with very low intra-family diversity and absence of Beijing genotypes. We found 66 different MIRU-VNTR patterns; the most frequent corresponded to Multiple Locus Variable Analysis (MLVA) MtbC15 patterns 860, 372 and 873. Twelve clusters, each with identical MIRU-VNTR and spoligotypes, gathered 35 patients. We found no association of genotype with drug resistant or MDR-TB. Clustering associated with SIT 50 and the H3 subfamily to which it belongs (p < 0.0001). The largest cluster involved isolates from three departments and displayed a genotype (SIT 50/MLVA 860) previously identified in Bolivian migrants into Spain and Argentina suggesting that this genotype is widespread among Bolivian patients. Our study presents a first overview of M. tuberculosis genotypes at risk of drug resistance circulating in Bolivia. However, results should be taken cautiously because the sample is small and includes a particular subset of M. tuberculosis population.  相似文献   

7.
Genotypes of Mycobacterium tuberculosis (MTB) are related to the geographic origin of the patients and population migration. The relationship between genotypes of MTB and clinical presentations has mainly focused on transmission of multi-drug resistant MTB strain in population. This study aimed to investigate the molecular epidemiology and dynamic change of MTB genotypes in Taiwan, and their association with clinical presentation among patients with pulmonary tuberculosis. A multi-center, two-year study which enrolled 516 patients with 516 MTB isolates was conducted, including: (1) 254 isolates from northern Taiwan; (2) 38 isolates from mid-western Taiwan; (3) 211 isolates from southern Taiwan; and (4) 13 isolates from the east coast of Taiwan. The isolates were genotyped with spoligotyping and standardized 12-loci-MIRU-VNTR method. The results showed Beijing/Beijing-like family was the major genotype of MTB in the northern (58%), eastern (53%), and southern (33%) regions. The second most widely spread lineage were the EAI-Manila (20% in the west and south) and Haarlem family (13-27% in the south, west, and east). According to the cluster analysis of 12-MIRU-VNTR genotypes, there were differences in distribution of MTB genotype between the northern and southern regions, and a temporal relationship between isolation year and 12-MIRU-VNTR genotype especially in loci 26 and 39 might exist. Furthermore, some patients with cavity lesions on chest films were associated with a cluster of Beijing family MTB strains, which can be defined by cluster analysis of 12-MIRU-VNTR genotype. However, the results of 12-loci-MIRU-VNTR genotyping in a longitudinal study should be interpreted with caution due to its short term instability. Further investigations of different molecular methodologies are necessary.  相似文献   

8.
目的 评价间隔区寡核苷酸分型(Spoligotyping)和基于结核分枝杆菌散在分布数目可变串联重复序列分析(MIRU-VNTR)方法在重庆地区儿童结核病分子流行病学中的应用.方法 收集重庆地区210株儿童结核分枝杆菌(MTB)临床分离株,应用上述两种分型方法进行比较分析.结果 采用Spoligotyping分型方法,210株菌可分为2个基因群44种基因型,其中最大的1个基因群即北京家族(北京基因型)含有130株菌(61.90%).采用MIRU-VNTR分析发现24个位点的多态性差异较大,不同MIRU位点组合(12、15和24位点)的分辨率指数依次升高,后两个组合的差异是由位点ETR-B引起.各位点和各位点组合在北京家族菌株中的分辨率指数均高于非北京家族菌株.结论 重庆地区儿童MTB具有明显的基因多态性,其主要流行型为北京家族.在结核病原学监测中,可先采用Spoligotyping,再对成簇菌株进行15位点与ETR-B组合二次分型的联合分型策略,可提高分子流行病学调查效果.
Abstract:
Objective To evaluate the application of spacer oligonucleotide typing (Spoligotyping) and mycobaeterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR) analysis in the molecular-epidemiological study of tuberculosis and to discuss the characteristics of pediatric Mycobacterium (M.) tuberculosis strains in Chongqing. Methods M. tuberculosis strains isolated and typed by Spoligotyping and MIRU-VNTR respectively, from the children patients in Chongqing and to compare the results from both methods, epidemiologically. Results By means of Spoligotyping, 210 clinical isolates were divided into 2 gene groups, displaying 44 genotypes. Among them, the biggest group was M. tuberculosis Beijing family, including 130 strains (61.90%) ,using the Spoligotyping. From the results of MIRU-VNTR, 24 loci showed different polymorphism and the HGI of different loci set (12 old loci, 15 basic loci and 24-loci set) increased accordingly. The subtle difference in HGI was originated from one locus ETR-B, which was included in the 24-locus system. The diversity of each loci and MIRU-VNTR set for non-Beijing genotype strains was higher than that of the Beijing genotype strains. Conclusion In this study, it was preliminarily confirmed the existence of high polymorphism of M. tuberculosis while the Beijing Family was the main genotype and main prevalent strain in children of Chongqing area. Spoligotyping prior to 15-locus with ETR-B combination seemed more suitable for the massive epidemiological investigation of pediatric tuberculosis patients.  相似文献   

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In this study we assessed first-line anti-tuberculosis drug resistance and the genotypic distribution of Mycobacterium tuberculosis complex (MTBC) isolates that had been collected from consecutive new tuberculosis patients enrolled in two clinical trials conducted in Guinea between 2005 and 2010. Among the total 359 MTBC strains that were analyzed in this study, 22.8% were resistant to at least one of the first line anti-tuberculosis drugs, including 2.5% multidrug resistance and 17.5% isoniazid resistance, with or without other drugs. In addition, further characterization of isolates from a subset of the two trials (n = 184) revealed a total of 80 different spoligotype patterns, 29 “orphan” and 51 shared patterns. We identified the six major MTBC lineages of human relevance, with predominance of the Euro-American lineage. In total, 132 (71.7%) of the strains were genotypically clustered, and further analysis (using the DESTUS model) suggesting significantly faster spread of LAM10_CAM family (p = 0.00016). In conclusion, our findings provide a first insight into drug resistance and the population structure of the MTBC in Guinea, with relevance for public health scientists in tuberculosis control programs.  相似文献   

10.
The objectives of this study were to determine drug resistance pattern in new and previously treated tuberculosis (TB) patients, to assess function of TB control program, and to characterize multidrug resistant TB (MDR-TB) by molecular fingerprinting methods. Anti-microbial susceptibility testing (AST) to the first line anti-TB drugs was performed on L?wenstein-Jensen (middlebrook 7H10) medium according to the proportion method. Molecular fingerprinting of all MDR strains was performed by spoligotyping and MIRU-VNTR. Mycobacterium tuberculosis strains were isolated from 53 Iraqi patients with pulmonary TB. Thirty eight patients (71.7%) tested cases, and 15 (28.3%) were previously treated. Four of the 38 new cases (10.5%) had resistant, of which 3 (7.9%) were MDR. Eight (53.3%) of the 15 previously treated patients had resistant strains, of which 7 (46.7%) were MDR. Spoligotyping of MDR strains showed CAS family (40%) as the predominant genotype. Using MIRU-VNTR typing, all isolates had a unique profile. MDR-TB prevalence is higher among previously treated patients than among the new cases. The many drug resistant strains, in absence of evidence of recent transmission and in combination with the many previously treated cases, highlight the need for an improved control program, coupled with a need to improve detection rate and early diagnosis of MDR-TB.  相似文献   

11.
Human tuberculosis is an infectious disease caused by bacteria from the Mycobacterium tuberculosis complex (MTBC). Although spoligotyping and MIRU-VNTR are standard methodologies in MTBC genetic epidemiology, recent studies suggest that Single Nucleotide Polymorphisms (SNP) are advantageous in phylogenetics and strain group/lineages identification. In this work we use a set of 79 SNPs to characterize 1987 MTBC isolates from Portugal and 141 from Northeast Brazil. All Brazilian samples were further characterized using spolygotyping. Phylogenetic analysis against a reference set revealed that about 95% of the isolates in both populations are singly attributed to bacterial lineage 4. Within this lineage, the most frequent strain groups in both Portugal and Brazil are LAM, followed by Haarlem and X. Contrary to these groups, strain group T showed a very different prevalence between Portugal (10%) and Brazil (1.5%). Spoligotype identification shows about 10% of mis-matches compared to the use of SNPs and a little more than 1% of strains unidentifiability. The mis-matches are observed in the most represented groups of our sample set (i.e., LAM and Haarlem) in almost the same proportion. Besides being more accurate in identifying strain groups/lineages, SNP-typing can also provide phylogenetic relationships between strain groups/lineages and, thus, indicate cases showing phylogenetic incongruence.Overall, the use of SNP-typing revealed striking similarities between MTBC populations from Portugal and Brazil.  相似文献   

12.
目的 了解厦门市结核分枝杆菌基因类型分布及主要流行基因群情况,并建立分型数据库。方法 采用实时荧光PCR法对厦门市2013 - 2015年分离到的466株结核分枝杆菌临床分离株进行菌株确认,然后采用间隔区寡核苷酸分型方法(spoligotyping)对其进行基因分型。分型结果与SpolDB4数据库进行比对,并使用Bionumeric6.6.4软件进行基因聚类分析。结果 466株菌均为结核分枝杆菌,基因分型分成96种基因型别,62种数据库中有相应的SIT编号,34种为新的型别。97.64%(455/466)的菌构成了15个基因簇。466株菌属于7个基因家族及未定义家族,排在前三的分别为:Beijing(北京)家族60.09%(280/466)、T家族21.03%(98/466)、H家族5.58%(26/466)。结论 厦门市结核分枝杆菌基因型别呈现多样性,北京家族为主要的流行基因群。  相似文献   

13.
In recent years the State of New South Wales (NSW), Australia, has maintained a low tuberculosis incidence rate with little evidence of local transmission. Nearly 90% of notified tuberculosis cases occurred in people born in tuberculosis-endemic countries. We analyzed geographic, epidemiological and genotypic data of all culture-confirmed tuberculosis cases to identify the bacterial and demographic determinants of tuberculosis hotspot areas in NSW. Standard 24-loci mycobacterium interspersed repetitive unit-variable number tandem repeat (MIRU-24) typing was performed on all isolates recovered between 2009 and 2013. In total 1692/1841 (91.9%) cases with confirmed Mycobacterium tuberculosis infection had complete MIRU-24 and demographic data and were included in the study. Despite some year-to-year variability, spatio-temporal analysis identified four tuberculosis hotspots. The incidence rate and the relative risk of tuberculosis in these hotspots were 2- to 10-fold and 4- to 8-fold higher than the state average, respectively. MIRU-24 profiles of M. tuberculosis isolates associated with these hotspots revealed high levels of heterogeneity. This suggests that these spatio-temporal hotspots, within this low incidence setting, can represent areas of predominantly imported infection rather than clusters of cases due to local transmission. These findings provide important epidemiological insight and demonstrate the value of combining tuberculosis genotyping and spatiotemporal data to guide better-targeted public health interventions.  相似文献   

14.
目的 了解2018年10月至2019年1月间泰州地区急性胃肠炎疫情主要致病原,掌握其传播流行规律。方法 采集学校聚集性疫情中患者的咽拭子和肛拭子标本,进行病原学核酸检测,测定阳性疫情株VP1基因序列,构建系统发生树,分析疫情株所属流行亚群,推测该流行亚群做传染病人口学模型和传播路径,以及VP1基因变异性分析。结果 共采集疫情样100人份,检出诺如病毒GII型阳性45份,测定其中20份标本VP1基因序列,除1份为GII.3型外,其余均为GII.2亚型,该GII.2型疫情株间同源性平均达99.4%,其与2016-2017年中国、日本流行株属于同一流行亚群,该亚群起源于上海地区,且仍处于流行上升阶段。结论 本时间段泰州市急性胃肠炎学校聚集性疫情的主要致病原是GII.2型诺如病毒,其属于一个活跃的流行亚群。  相似文献   

15.
Bovine Anaplasmosis caused by Anaplasma marginale is a worldwide disease prevalent in tropical and subtropical regions where Rhipicephalus microplus is considered the most significant biological vector. Molecular markers previously applied for A. marginale typing are efficient for isolate discrimination but they are not a suitable tool for studying population structure and dynamics. Here we report the development of an MLST scheme based on the study of seven genes: dnaA, ftsZ, groEl, lipA, recA, secY and sucB. Five annotated genomes (Saint Maries, Florida, Mississippi, Puerto Rico and Virginia) and 53 bovine blood samples from different world regions were analyzed. High nucleotide diversity and a large proportion of synonymous substitutions, indicative of negative selection resulted from DnaSP 5.00.02 package application. Recombination events were detected in almost all genes, this evidence together with the coexistence of more than one A. marginale strain in the same sample might suggest the superinfection phenomena as a potential source of variation. The allelic profile analysis performed through GoeBURST shown two main CC that did not support geography. In addition, the AMOVA test confirmed the occurrence of at least two main genetically divergent groups. The composition of the emergent groups reflected the impact of both historical and environmental traits on A. marginale population structure. Finally, a web-based platform “Galaxy MLST-Pipeline” was developed to automate DNA sequence editing and data analysis that together with the Data Base are freely available to users.The A. marginale MLST scheme developed here is a valuable tool with a high discrimination power, besides PCR based strategies are still the better choice for epidemiological intracellular pathogens studies. Finally, the allelic profile describe herein would contribute to uncover the mechanisms in how intracellular pathogens challenge virulence paradigm.  相似文献   

16.
目的利用间隔区寡核苷酸分型(Spoligotyping)方法对甘肃省结核分枝杆菌流行株进行分型研究,了解目前甘肃省结核分枝杆菌流行株基因型的基本情况,为甘肃省结核病防控提供分子流行病学依据。方法采用Spoligo-typing对甘肃省228株临床分离结核分枝杆菌进行基因分型,结果使用Bionumerics-5.01软件统计、分析,并与SpolDB4数据库进行比对,得出菌株分型结果。结果228株结核分枝杆菌被分为北京家族(Beijingfamily)和非北京家族(Non-Beijingfamily)2大基因群,其中北京家族基因群占88.6%(202/228)。非北京家族基因群为11.4%(26/228),228株结核分枝杆菌构成23个基因簇,其中独立基因型12个。结论北京家族基因群菌株在甘肃省结核分枝杆菌流行株中占据绝对优势地位,对该基因群菌株引发的结核病应给予密切关注并应加强对北京家族基因型菌株生物学特性研究。  相似文献   

17.
In the present study, genetic diversity analysis of Mycobacterium tuberculosis isolated from patients attending a tertiary care hospital, North India, has been attempted. Eighty three isolates of M. tuberculosis were subjected to DNA fingerprinting using spoligotyping and IS6110-RFLP techniques. Spoligotype patterns showed that central Asian (32.5%), ill defined T (13.2%) and Beijing (10.8%) families were predominant in ongoing transmission of the bacterium. Two STs; ST26 (CAS_Delhi) and ST1 (Beijing) represented 36.1% of the total M. tuberculosis population in eastern Uttar Pradesh, North India. IS6110 RFLP analysis showed that isolates having low and zero copy number of the IS element were 15.6% and 19.2%, respectively. Out of the 47 isolates clustered by spoligotyping, 40 could be further differentiated as unique strains by IS6110-RFLP. Therefore, this study recommends that both the techniques be used simultaneously for DNA fingerprinting of M. tuberculosis in India.  相似文献   

18.
DNA fingerprinting data for 4,207 Mycobacterium tuberculosis isolates were combined with data from a computer program (Origins). Largest population groups were from England (n = 1,031) and India (n = 912), and most prevalent strains were the Euro-American (45%) and East African–Indian (34%) lineages. Combining geographic and molecular data can enhance cluster investigation.  相似文献   

19.
目的 描述中国不同地区群体遗传结构特征,探索并评价不同分析方案控制队列样本群体遗传结构混杂因素的效果。方法 通过中国慢性病前瞻性研究(CKB)队列10个地区4 500例样本的全基因组关联研究数据,通过主成分分析提取样本第一、二主成分,绘制主成分二维图,并与样本地区来源相比较,分析我国不同地区样本的遗传结构特征。以CKB队列数据为基础,生成存在遗传结构差异、亲缘关系等队列样本特征的模拟数据集,探索并评价不同分析策略对膨胀因子(λ)的控制效果。结果 我国不同地区人群存在显著的群体遗传结构差异,人群遗传结构主成分分布与项目地区的地理分布基本一致,第一主成分对应不同地区的纬度,第二主成分对应不同地区的经度。生成的模拟数据集,直接进行关联分析假阳性率较高(λ=1.16),即使调整遗传结构主成分或根据地区进行亚组分析仍无法有效控制λ(λ>1.05);使用混合线性模型引入亲属关系矩阵作为随机效应量后,无论是否进一步调整遗传结构主成分,λ均得到有效控制(λ=0.99)。结论 我国不同地区人群遗传结构存在较大差异,在分子流行病学研究中需要谨慎处理群体遗传结构造成的研究偏倚;针对大队列数据遗传结构复杂、亲缘关系广泛等特征,需要使用混合线性模型进行关联分析。  相似文献   

20.
目的研究间隔区寡核苷酸序列(Spoligotyping)基因分型技术在河南省结核病分枝杆菌基因分型中的应用,了解河南省基因型种类和分布以及北京家族基因型在河南省的分布特征。方法应用2007年在河南省结核病防治机构实验室分离培养的310株结核分枝杆菌,设计引物,应用PCR和间隔区寡核苷酸分型(Spoligotyping)技术对结核分枝杆菌进行分型检测分析,基因分型分析经http://www.miru-vntrplus.org/MIRU/index.faces网站分析,统计学数据经卡方检验。结果对310株结核分枝杆菌临床分离株的Spoligotyping结果显示分为4个基因群(Beijing和Beijing近似群、T群、Manu群、S群),24个基因型,有267株为北京家族基因型,占86.1%,且北京家族基因型与MDR耐药有相关性;河南省较年轻人群(<60岁)感染的结核分枝杆菌中,北京家族基因型所占比例高于年老组(即>60岁组),北京家族基因型与年轻组的联系强于年老组;北京家族基因型的分布在不同的地区间有差异。结论河南省结核分枝杆菌以北京家族基因型为主要流行型,且与耐药及年龄、地域有相关性,重点监测北京家族基因型。  相似文献   

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