Our results suggest that fluoroquinolones are a risk factor for MRSA acquisition. Control measures to limit MRSA spread in LTCFs should also be based on optimization of fluoroquinolone use.

There was important inter-observer discrepancies in scoring clinical signs of respiratory disease, using relatively inexperienced observers. These disagreements may ultimately mean increased false negative or false positive diagnoses and incorrect treatment of cases. Visual assessment of clinical signs associated with bovine respiratory disease needs to be thoroughly validated when disease monitoring is based on the use of a clinical scoring system.