Résumé
Objective To investigate the HOOF genotyping characteristics of 83 Brucella (B.)melitensis strains isolated in Ulanqab of Inner Mongolia Autonomous Region from 2012 to 2015.Methods A total of 83 B.melitensis strains were detected by convention identification and AMOS-PCR,then HOOF protocol with eight VNTR locus were used for the genotyping of the strains,and the allelic diversity of each VNTR locus and the discriminatory power of VNTR typing of HOOF were assessed by Hunter-Gaston Discriminatory index.BioNumerics 5.0 was used for phylogenetic analysis and constructing dendrogram.Results All of the isolates were identified as B.melitensis strains by two identification methods.The complete eight VNTR locus had higher polymophism and diversity index was 0.998;and diversity index of six locus (1,2 and 4-7) were ≥0.678,discriminatory power of HOOF was mainly from this six higher diversity index locus.The 83 B.melitensis strains were classified into eight clusters and 76 genotypes,6 shared genotypes included 13 isolates,indicating that these brucellosis cases had epidemiological link,the other 70 strains had distinct genotypes,indicating that these cases had no epidemiological link.Conclusions The epidemic of human brucellosis in Ulanqab was characterized by local and sporadic outbreaks.Cross infection was related with the transfer of the sources of infection.
Résumé
Objective To investigate the HOOF genotyping characteristics of 83 Brucella (B.)melitensis strains isolated in Ulanqab of Inner Mongolia Autonomous Region from 2012 to 2015.Methods A total of 83 B.melitensis strains were detected by convention identification and AMOS-PCR,then HOOF protocol with eight VNTR locus were used for the genotyping of the strains,and the allelic diversity of each VNTR locus and the discriminatory power of VNTR typing of HOOF were assessed by Hunter-Gaston Discriminatory index.BioNumerics 5.0 was used for phylogenetic analysis and constructing dendrogram.Results All of the isolates were identified as B.melitensis strains by two identification methods.The complete eight VNTR locus had higher polymophism and diversity index was 0.998;and diversity index of six locus (1,2 and 4-7) were ≥0.678,discriminatory power of HOOF was mainly from this six higher diversity index locus.The 83 B.melitensis strains were classified into eight clusters and 76 genotypes,6 shared genotypes included 13 isolates,indicating that these brucellosis cases had epidemiological link,the other 70 strains had distinct genotypes,indicating that these cases had no epidemiological link.Conclusions The epidemic of human brucellosis in Ulanqab was characterized by local and sporadic outbreaks.Cross infection was related with the transfer of the sources of infection.