Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae and Methicillin-Resistant Staphylococcus aureus in pig farms in Switzerland.

The presence of Methicillin-Resistant Staphylococcus aureus (MRSA) in pig farms has been widely reported, and the emergence of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) has been documented in several countries. However, data for Switzerland are very scarce. This study aimed to compare changes in the prevalence of MRSA in Swiss pig farms between 2008 and 2015 and make the first ever estimates of the presence of ESBL-E and carbapenemase producers in pigs and pig farm workers. Results showed that ESBL-E was present in both pigs and farm workers and that the proportion of farms with MRSA had increased fourfold in seven years (from 7% to 31%). Associations between antibiotic use and resistant bacteria carriage were shown.