title: Molecular epidemiology of Corynebacterium pseudotuberculosis isolated from horses in California.
abstract: Corynebacterium pseudotuberculosis biovar Equi is an important pathogen of horses. It is increasing in frequency in the United States, and is responsible for various clinical forms of infection, including external abscesses, internal abscesses of the abdominal or thoracic cavities, and ulcerative lymphangitis. The host/pathogen factors dictating the form or severity of infection are currently unknown. Our recent investigations have shown that genotyping C. pseudotuberculosis isolates using enterobacterial repetitive intergenic consensus (ERIC)-PCR is useful for understanding the evolutionary genetics of the species as well for molecular epidemiology studies. The aims of the present study were to assess (i) the genetic diversity of C. pseudotuberculosis strains isolated from horses in California, United States and (ii) the epidemiologic relationships among isolates. One hundred and seven C. pseudotuberculosis biovar Equi isolates from ninety-five horses, and two C. pseudotuberculosis biovar Ovis strains, C. pseudotuberculosis ATCC 19410Ttype strain and C. pseudotuberculosis 1002 vaccine strain, were fingerprinted using the ERIC 1+2-PCR. C. pseudotuberculosis isolated from horses showed a high genetic diversity, clustering in twenty-seven genotypes with a diversity index of 0.91. Minimal spanning tree showed four major clonal complexes with a pattern of temporal clustering. Strains isolated from the same horse showed identical ERIC 1+2-PCR genotype, with the exception of two strains isolated from the same animal that showed distinct genotypes, suggesting a co-infection. We found no strong genetic signals related to clinical form (including internal versus external infections). However, temporal clustering of genotypes was observed.
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Dionei J
authors.initials: DJ
authors.lastname: Haas
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; Departamento de Medicina Veterinária, Universidade Federal de Lavras, Lavras, Minas Gerais, Brazil.
authors.forename: Elaine M S
authors.initials: EM
authors.lastname: Dorneles
authors.affiliation: Department of Medicine and Epidemiology, University of California, Davis, California, USA.
authors.forename: Sharon J
authors.initials: SJ
authors.lastname: Spier
authors.affiliation: Department of Medicine and Epidemiology, University of California, Davis, California, USA.
authors.forename: Scott P
authors.initials: SP
authors.lastname: Carroll
authors.affiliation: Department of Medicine and Epidemiology, University of California, Davis, California, USA.
authors.forename: Judy
authors.initials: J
authors.lastname: Edman
authors.affiliation: Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Vasco A
authors.initials: VA
authors.lastname: Azevedo
authors.affiliation: Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Marcos B
authors.initials: MB
authors.lastname: Heinemann
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address: alage@vet.ufmg.br.
authors.forename: Andrey P
authors.initials: AP
authors.lastname: Lage
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D002140:California / Q000453:epidemiology; D016000:Cluster Analysis; D003354:Corynebacterium Infections / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D016925:Corynebacterium pseudotuberculosis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics*; D021901:DNA, Intergenic / Q000235:genetics*; D014644:Genetic Variation; D005838:Genotype; D006734:Horse Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D006736:Horses / Q000382:microbiology; D017720:Molecular Epidemiology; D010802:Phylogeny; D012720:Severity of Illness Index
chemical_list: D004269:DNA, Bacterial; D021901:DNA, Intergenic
keywords: Co-infection; ERIC 1+2-PCR; Genotyping; Temporal clustering pattern; Ulcerative lymphangitis