TABLE 1

Incidence rate ratios of LA-MRSA CC398b

LA-MRSA CC398 status (receiving farm)LA-MRSA CC398 status (supplying farm)IRR95% CIP valuea
PositiveNegativeReference
Positive4.223.29–5.41<0.0001
Positive for L1NegativeReference
Positive for L19.884.66–20.9<0.0001
Positive for other than L10.0260.003–0.2010.0005
Positive for L2NegativeReference
Positive for L214.90–∞
Positive for other than L25.240–∞
Positive for L3NegativeReference
Positive for L32.391.40–4.090.0015
Positive for other than L30.2770.151–0.506<0.0001
  • a Only P values < 0.05 are shown.

  • b Abbreviations: L1, lineage 1; L2, lineage 2; L3, lineage 3; IRR, incidence rate ratio; 95% CI, 95% confidence interval.