title: Molecular typing of Mycoplasma agalactiae: tracing European-wide genetic diversity and an endemic clonal population.
abstract: Mycoplasma agalactiae causes chronic infections in small ruminants and remains endemic in many regions of the world, despite intensive and costly eradication programs. In this study, the innate genomic plasticity of M. agalactiae was exploited to design and assess a combination of molecular epidemiological tools to trace the pathogen in different geographic locations and to understand its emergence or re-emergence after eradication campaigns. For this purpose, two collections of M. agalactiae isolates, representing European outbreaks or localized endemic disease in a single region of France, were subjected to RFLP (Restriction Fragment Length Polymorphism) analyses using two sets of DNA probes (distributed across the genome and specific for the vpma gene locus), and a previously described VNTR (Variable Number Tandem Repeats) analysis. A combination of four genome-specific DNA probes and two VNTRs gave the highest discriminative power. Molecular typing revealed that, while isolates from diverse geographical origins fell into clearly different groups, the endemic disease repeatedly observed in the Western Pyrenees region over the past 30 years has been caused by a unique subtype of M. agalactiae. This indicates that the re-emergence of the pathogen after seemingly successful eradication programs is not due to the importation of exotic strains, but to the persistence of local reservoirs of infection.
authors.affiliation: Université de Toulouse, INP-ENVT, UMR 1225, F-31076 Toulouse, France.
authors.forename: Laurent-Xavier
authors.initials: LX
authors.lastname: Nouvel
authors.forename: Marc Serge
authors.initials: MS
authors.lastname: Marenda
authors.forename: Michelle Diane
authors.initials: MD
authors.lastname: Glew
authors.forename: Eveline
authors.initials: E
authors.lastname: Sagné
authors.forename: Philippe
authors.initials: P
authors.lastname: Giammarinaro
authors.forename: Florence
authors.initials: F
authors.lastname: Tardy
authors.forename: François
authors.initials: F
authors.lastname: Poumarat
authors.forename: Renate
authors.initials: R
authors.lastname: Rosengarten
authors.forename: Christine
authors.initials: C
authors.lastname: Citti
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques / Q000379:methods; D021821:Communicable Diseases, Emerging / Q000382:microbiology; D015342:DNA Probes / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics*; D060740:Disease Eradication; D019353:Endemic Diseases; D005602:France / Q000453:epidemiology; D005798:Genes, Bacterial; D014644:Genetic Variation; D018598:Minisatellite Repeats; D017720:Molecular Epidemiology / Q000379:methods; D058889:Molecular Typing / Q000379:methods*; D009175:Mycoplasma Infections / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control; D045644:Mycoplasma agalactiae / Q000145:classification / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D015342:DNA Probes; D004269:DNA, Bacterial