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Objective:To analyze the incidence of brucellosis and the genotypes of Brucella isolates or nucleic acids in Shaanxi Province, to get the epidemiological and molecular genetic characteristics, and to provide scientific basis for precise prevention and control of human brucellosis. Methods:Log into the Chinese Disease Control and Prevention Information System, collect the incidence data of human brucellosis of Shaanxi Province in 2020, and analyze the epidemiological characteristics. Bacteriology and PCR methods were used to identify the isolates or nucleic acids, and multiple locus variable-number tandem repeat analysis (MLVA) was used for molecular typing. BioNumerics (Version 7.6) software was used to analyze the results of MLVA.Results:In 2020, 1 086 cases of human brucellosis were reported in Shaanxi Province, the incidence rate was 2.80/100 000, involving 86 counties (districts), the epidemic peak was from March to September (865 cases), male-to-female ratio was 2.68 ∶ 1.00 (791 ∶ 295), 79.74% (866 cases) in the age group of 30 to 69 years old, and 83.43% (906 cases) of the cases were farmers. Biotype identification of 36 isolates showed that 4 isolates were mutant Brucella melitensis, 3 isolates were Brucella melitensis 1 and 29 isolates were Brucella melitensis 3. The 36 isolates and 7 nucleic acids were identified as Brucella by BCSP31-PCR and Brucella melitensis by AMOS-PCR. MLVA-16 genotyping, panel1 showed two genotypes: type 42 (1-5-3-13-2-2-3-2) and type 63 (1-5-3-13-2-3-3-2), panel2A showed 4-41-8 and panel2B showed high variability. Thirty-six isolates and 7 nucleic acids were divided into 33 genotypes, of which 27 genotypes were single isolates and 6 genotypes were shared. Conclusions:The situation of human brucellosis prevention and control in Shaanxi Province is grim. MLVA-16 is a mature genotyping method, which determines the existence of multiple genotypes of Brucella isolates or nucleic acids in Shaanxi Province, which can provide scientific information for precise prevention and control of human brucellosis, outbreak analysis and epidemiological traceability.
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Objective To analyze the molecular characteristics of Brucella strains isolated from Nanjing,understand strains genotying and clustering,and to provide a basis for prevention and treatment of brucellosis.Methods Multilocus sequence typing (MLST) and multiple locus variable-number tandem repeat analysis (MLVA) were used to analyze and characterize Brucella ovis strains isolated from 7 cases of sporadic cases in Nanjing Drum Tower Hospital,the Affiliated Hospital of Nanjing University Medical School,from 2011-2016,and cluster analysis was did with reference strain data from Jiangsu Province.Results The results showed that 7 strains were defined as sequence type (ST) 8 by MLST.They were typed into 7 subtypes and clustered in the "Middle Mediterranean Cluster" by MLVA.Strain NJ-2011-1 and two strains isolated from other cities in Jiangsu had the same MLVA genotype.Conclusions The results reveal ST8 is the predominant genotype in Nanjing.They have clustered in the "Middle Mediterranean Cluster" by MLVA.The 7 strains are sporadic.The transmission routes and risk factors are more complicated in the city.Various departments should strengthen the cooperation to control the source.
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Two cross-sectional studies were carried out in 2013 and 2015 monitoring for Mycoplasma hyopneumoniae presence in a swine farm. In these studies, the genetic diversity of M. hyopneumoniae was assessed in clinical specimens using a Multiple Locus Variable-number tandem repeat Analysis (MLVA) targeting P97 R1, P146 R3 and H4 loci. The samples from August 2015 showed the MLVA profile prevalent in June 2013, therefore it can be concluded that a same genetic type of M. hyopneumoniae can persist for at least two years in a closed herd. In addition, the nested PCR reactions implemented in this study showed to be useful for MLVA typing in non-invasive clinical samples.
Dos estudios transversales fueron realizados en los anos 2013 y 2015 monitorizando la presencia de Mycoplasma hyopneumoniae en una piara. En esos estudios la diversidad genética de M. hyopneumoniae fue evaluada a partir de muestras clínicas utilizando un análisis multilocus de regiones repetidas en tándem (MLVA) de los loci P97 R1, P146 R3 y H4. Las muestras colectadas en agosto del 2015 mostraron el perfil de MLVA prevalente en junio del 2013, por lo tanto, se puede concluir que el mismo tipo genético de M. hyopneumoniae puede persistir por al menos 2 años en una piara sin reposición externa de animales. Además, las reacciones de PCR anidadas implementadas en este estudio mostraron ser útiles para la tipificación por MLVA a partir de muestras clínicas no invasivas.
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Animals , Mycoplasma hyopneumoniae , Pneumonia of Swine, Mycoplasmal , Swine , Genetic Variation , Cross-Sectional Studies , Minisatellite Repeats , Mycoplasma hyopneumoniae/isolation & purification , Mycoplasma hyopneumoniae/genetics , Pneumonia of Swine, Mycoplasmal/geneticsABSTRACT
Objective To understand the genotype of the Yersinia (Y.) pestis strains isolated from Heqing county,Yunnan province in 2017 and provide evidence for the prevention and control of plague in this area.Methods Ten Y.pestis strains isolated from Heqing were typed by the detections of different region (DFR) and clustered regularly interspaced short palindromic repeats (CRISPRs) as well as multiple-locus variable-number tandem repeat analysis (MLVA).And the results were compared with those of the 93 Y.pestis strains from the adjacent plague foci of Heqing obtained from the established database for clustering analysis.Results The results showed that Heqing strains had the same type of DFR (Genomovar 05) and CRISPRs (Cluster Ca7,Type 22) with isolates from the plague focus in Lijiang.Heqing strains and Lijiang strains were in the same cluster in MST and only VNTR loci N2117 and M23 of Heqing strains were different from that of Lijiang strains.Conclusion The Y.pestis strains isolated from Heqing in 2017 were highly homogenous with the strains isolated from wild rodents in plague focus in Lijiang,and Heqing plague might be the result of further southward spread of Lijiang plague.
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Objective To understand the genotype of the Yersinia (Y.) pestis strains isolated from Heqing county,Yunnan province in 2017 and provide evidence for the prevention and control of plague in this area.Methods Ten Y.pestis strains isolated from Heqing were typed by the detections of different region (DFR) and clustered regularly interspaced short palindromic repeats (CRISPRs) as well as multiple-locus variable-number tandem repeat analysis (MLVA).And the results were compared with those of the 93 Y.pestis strains from the adjacent plague foci of Heqing obtained from the established database for clustering analysis.Results The results showed that Heqing strains had the same type of DFR (Genomovar 05) and CRISPRs (Cluster Ca7,Type 22) with isolates from the plague focus in Lijiang.Heqing strains and Lijiang strains were in the same cluster in MST and only VNTR loci N2117 and M23 of Heqing strains were different from that of Lijiang strains.Conclusion The Y.pestis strains isolated from Heqing in 2017 were highly homogenous with the strains isolated from wild rodents in plague focus in Lijiang,and Heqing plague might be the result of further southward spread of Lijiang plague.
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Objective A suspected strain of Brucella canis isolated in Hebei Province in 2015 was identified and its genetic characteristics were analyzed.Methods After conventional identification of the bacteria strain,multiplex polymerase chain reaction (M-PCR) and multiple-locus variable-number tandem-repeat analysis (MLVA) were conducted to determine its species and genetic characteristics.Results The strain was identified as Brucella canis by conventional subtyping and M-PCR.Using Panel 1,the strain was genotype 3,using Panel 2A,the strain was genotype 28.It was closely clustered with Brucella canis,and differences of repeated numbers at variablenumber tandem-repeat (VNTR) loci Bruce04,Bruce07,Bruce09 and Bruce16 were also displayed.Conclusions The conventional subtyping and molecular methods can improve the stability and accuracy of the identification.Genetic characteristics of the strain is closely related to that of Brucella canis.
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Objective To explore the genetic relationship between the Chinese and the foreign species of Francisella tularensis.Methods Based on our own findings and from the literature,17 SNP,4 INDEL,and 12 VNTR were selected for phylogenetic analysis on 39 strains of F.tularensis,including 10 strains of Chinese F.tularensis and 29 strains of foreign F.tularensis that had been sequenced and published.SNP-INDEL and MLVA were used for the separation and combination.Results Data from the combined analysis indicated that 3 strains of Chinese F.tularensis with Japanese FSC022 were assigned to B5;3 strains,with Swedish FSC200 to B1;3 strains with American OSU18 to B2 and 1 strain with French FTNF002-00,German F92,and American OR96246 to B4,respectively.10 strains of Chinese F.tularensis were assigned to 4 clades and the result demonstrated a wide diversity of F.tularensis subsp.holarctica in China.Conclusion A set of simple and robust typing tools for F.tularensis subsp.holarctica were established in this study.Based on the results,F.tularensis subsp.holarctica might have had its origins in Asia.
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Objective A suspected Brucella strain, isolated from the first case of mink breeder in Hebei Province was identified and genetic characteristics were analyzed.Methods Blood sample of the patient with brucellosis was collected at brucellosis laboratory of Hebei Provincial Center for Disease Control and Prevention;anti-Brucella antibody was tested and Brucella was isolated by two phase culture bottles.Conventional methods were used to identify the isolated strain, the genetic characteristics were analyzed by multiple-locus variable-number tandem-repeat analysis (MLVA).Results Anti-Brucella antibody was tested positive.The isolated strain was identified as Brucella melitensis biovar 1 using the conventional methods.Using Pannel 1, the strain was genotype 42 clustering to the East Mediterranean Brucella Melitensis group.It was closely clustered with Brucella melitensis biovar 3, and difference of repeated numbers at variable-number tandem-repeat (VNTR) loci bruce19 was also displayed.Conclusion The case is the first brucellosis case of mink breeder in Hebei Province, the isolated strain from this patient is identified as Brucella melitensis biovar 1 and the genetic characteristics of the strain are closely related to those of Brucella melitensis biovar 3.
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Leptospirosis is the most widespread zoonosis in the world and significant efforts have been made to determine and classify pathogenic Leptospira strains. This zoonosis is maintained in nature through chronic renal infections of carrier animals, with rodents and other small mammals serving as the most important reservoirs. Additionally, domestic animals, such as livestock and dogs, are significant sources of human infection. In this study, a multiple-locus variable-number tandem repeat analysis (MLVA) was applied to genotype 22 pathogenic Leptospira strains isolated from urban and periurban rodent populations from different regions of Argentina. Three MLVA profiles were identified in strains belonging to the species Leptospira interrogans (serovars Icterohaemorrhagiae and Canicola); one profile was observed in serovar Icterohaemorrhagiae and two MLVA profiles were observed in isolates of serovars Canicola and Portlandvere. All strains belonging to Leptospira borgpetersenii serovar Castellonis exhibited the same MLVA profile. Four different genotypes were isolated from urban populations of rodents, including both mice and rats and two different genotypes were isolated from periurban populations.
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Animals , Mice , Rats , Leptospira/genetics , Rodentia/microbiology , Argentina , Didelphis/microbiology , Genotype , Genotyping Techniques/methods , Leptospira interrogans serovar canicola/genetics , Leptospira interrogans serovar icterohaemorrhagiae/genetics , Leptospira interrogans serovar pomona/genetics , Leptospira/classification , Leptospira/isolation & purification , Leptospirosis/transmission , Serogroup , Serotyping , Tandem Repeat Sequences/genetics , Urban Population , Virulence/geneticsABSTRACT
Objective To inspect the source of an outbreak with Mycoplasma pneumoniae (Mp).Methods We carried out real-time PCR to analyze specimens collected from pediatric patients in Beijing during January 2010 to May 2012,diagnosed as pneumonia or a respiratory infection according to clinical symptoms.These positive samples were analyzed by the M-P typing system(M:multiple-locus variable-number tandem-repeat analysis,MLVA; P:P1-restriction fragment length polymorphism analysis,P1-RFLP).Results Sixty-nine specimens were tested positive to Mp by the real-time PCR in 446 specimens from pediatric patients.The infection rate was 11.69％,15.56％ and 20.00％ respectively in 2010,2011 and the first half of 2012.According to the M-P system,11 distinct genotypes were identified from 69 positive specimens,M43562P1 and M53562P1 were the two main genotypes that showed an increasing trend from 2010 to 2011,and M33562P1 and M63562P1 showed an increasing trend from 2011 to 2012 in China.Conclusion During this international Mp epidemic,the infection rate of Mp was also increase in Beijing in 2011,and M43562P1 and M53562P1 were the two main genotypes.Among them,M43562 were consistent with pop genotypes in Europe,and M53562 were consistent with pop genotype in Israel.The M-P system would be valuable to monitor the epidemic of Mp in different countries in the world.
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Objective To establish the standard operating procedures on multiple locus variable number tandem repeat analysis and to evaluate the values in identification of Brucella(B.) melitensis and epidemiological trace-back.Methods Sixteen B.melitensis,22 B.abortus,21 B.suis and 10 B.cnais were investigated by Brucella MLVA-16 genotyping scheme.All data were analyzed using BioNumerics version 5.1 software (AppliedMaths,Belgium).Clustering analysis was based on the categorical coefficient and unweighted pair group method using arithmetic averages(UPGMA) method.Polymorphism at each locus was quantified using Nei's diversity index.Resultant genotypes were compared using the web-based Brucella 2010 MLVA database.Results MLVA methods were successfully established and some strains can be clustered.Bruce06,bruce08,bruce11,bruce12,bruce42,bruce43,bruce45 and bruce55 were useful for species identification of Brucella isolates.Bruce04,bruce07,bruce09,bruce16 and bruce 30 afforded a higher discriminatory power for investigation of strain relatedness in regions of endemicity.Conclusions TheMLVAmethod has proved to be highly discriminatory and epidemiological concordance and is easy for Brucellosis surveillance in province-level lab.
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Bacillus (B.) anthracis is the pathogen that causes fatal anthrax. Strain-specific detection of this bacterium using molecular approaches has enhanced our knowledge of microbial population genetics. In the present study, we employed molecular approaches including multiple-locus variable-number tandem repeat analysis (MLVA) and canonical single-nucleotide polymorphism (canSNP) analysis to perform molecular typing of B. anthracis strains isolated in Korea. According to the MLVA, 17 B. anthracis isolates were classified into A3a, A3b, and B1 clusters. The canSNP analyses subdivided the B. anthracis isolates into two of the three previously recognized major lineages (A and B). B. anthracis isolates from Korea were found to belong to four canSNP sub-groups (B.Br.001/2, A.Br.005/006, A.Br.001/002, and A.Br.Ames). The A.Br.001/002 and A.Br.Ames sub-lineages are closely related genotypes frequently found in central Asia and most isolates were. On the other hand, B. anthracis CH isolates were analyzed that belonged to the B.Br.001/002 sub-group which found in southern Africa, Europe and California (USA). B.Br.001/002 genotype is new lineage of B. anthracis in Korea that was not found before. This discovery will be helpful for the creation of marker systems and might be the result of human activity through the development of agriculture and increased international trade in Korea.