Table 2.

Logistic regression analysis of multiple virulence factors and B2 status as predictors of mouse lethalitya

Lethality criterionMultiple virulence factorsbB2 phylogenetic group
RRcPRRP
≥1 mouse (model 1)82<0.00160.04
All 10 mice (model 2)310.00320.33
Accelerated lethalityd (model 3)370.00130.11
  • a Results are based on data from reference 1.

  • b Two or more factors including hemolysin, MRHA, K1 antigen, sfa/foc, pap, hly, and ibe10 (not afa and aer).

  • c RR, relative risk.

  • d Accelerated lethality as indicated by + in the column labeled “Lethality in mice” of Table 1 of reference1.