Meticillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC) 398 is a genetic lineage associated with livestock, especially pigs.
The authors investigated the role of pig trade in the transmission of MRSA CC398 between farms using pulsed-field gel electrophoresis (PFGE), a highly discriminatory method for strain typing. PFGE analysis of 58 MRSA isolates from a retrospective study in the Netherlands and a prospective study in Denmark provided molecular evidence that the strains present in five of the eight recipient farms were indistinguishable from those occurring in the corresponding supplying farm.
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The molecular typing data confirm the findings of a previous risk-analysis study indicating that trading of colonised pigs is a vehicle for transmission of MRSA CC398.
C. Espinosa-Gongora, E. M. Broens, A. Moodley, J. P. Nielsen and L. Guardabassi. Transmission of MRSA CC398 strains between pig farms related by trade of animals. Veterinary Record 2012. vOL. 170 (22); 170:564 doi:10.1136/vr.100704