Genotyping of Mycobacterium bovis from cattle in Central Pampas in Argentina: temporal and regional trends

SHIMIZU, ERNESTO; MACÍAS ANALÍA; PAOLICCHI, FERNANDO; MAGNANO, GABRIEL; ZAPATTA, LAURA; FERNÁNDEZ, ANALÍA; CANAL ANA; GARBACCIO, SERGIO; CATALDI, ANGEL; CAIMI, KARINA; ZUMÁRRAGA, MARTÍN JOSÉ

MEMóRIAS DO INSTITUTO OSWALDO CRUZ.

FUNDACO OSWALDO CRUZ

Lugar: Rio de Janeiro; Año: 2014 vol. 109 p. 236 - 245

0074-0276

Mycobacterium bovis is the causative agent of bovine tuberculosis, a disease that affects approximately 5% of Argentinean cattle. Among the molecular methods for genotyping, the most convenient are spoligotyping and genotyping by Variable Number of Tandem Repeat (VNTR). A total of 378 samples from bovines with visible lesions compatible with tuberculosis were taken in slaughterhouses from three provinces, yielding 265 M. bovis spoligotyped isolates distributed in 35 spoligotypes. In addition, 197 isolates were also typed by VNTR and 54 combined VNTR types were detected. There were 24 clusters and 27 orphan types. When both typing methods were combined, 98 spoligotyping and VNTR types were observed with 27 clusters and 71 orphan types. By performing a meta-analysis with previous spoligotyping results, we identified regional and temporal trends in the structure population of M. bovis. For SB0140, the most predominant spoligotype in Argentina, the percentage of prevalence remained high in the different periods, varying from 25.5 % to 57.8% (1994 to 2011). In contrast, the second and third most prevalent spoligotypes showed important fluctuations. This study shows that there has been an expansion of ancestral lineages as demonstrated by spoligotyping. However, ETR typing suggests dynamic changes in the clonal population of this microorganism.