Table 7. Logistic regression modelsa,b,c assessing the association between source type, location type, and the occurrence of select plasmid incompatibility types and antimicrobial resistance genes in phenotypically resistant Escherichia coli isolates from wildlife and soil samples collected on swine farms and conservation areas in southern Ontario, 2011−2013 (n = 146, dataset B).
| Independent variable | Sub-category | tet(A) | tet(B) | bla TEM-1 | |||
| OR (95% CI) | p-value | OR (95% CI) | p-value | OR (95% CI) | p-value | ||
| Location type | Conservation area | REF | 0.031a (global) | REF | 0.331b (global) | REF | 0.437b (global) |
| Swine farm | 2.06 (1.06−4.01) | 0.033 | 1.64 (0.60−4.44) | 0.331 | 0.69 (0.26−1.77) | 0.438 | |
| Source type | Soil | REF | 0.698b (global) | REF | 0.938b (global) | REF | 0.029b,c (global) |
| Wildlife | 0.88 (0.44−1.76) | 0.716 | 0.97 (0.45−2.08) | 0.938 | 3.13 (1.35−7.22) | 0.008 | |
| sul1 | sul2 | ant(3”)-Ia | |||||
| OR (95% CI) | p-value | OR (95% CI) | p-value | OR (95% CI) | p-value | ||
| Location type | Conservation area | REF | 0.998a (global) | REF | 0.914a (global) | REF | 0.333a (global) |
| Swine farm | 1.0 (0.29−3.50) | 0.998 | 0.96 (0.44−2.08) | 0.914 | 1.54 (0.64−3.75) | 0.336 | |
| Source type | Soil | REF | 0.151a (global) | REF | 0.553a (global) | REF | 0.655a (global) |
| Wildlife | 2.07 (0.77−5.57) | 0.151 | 1.27 (0.58−2.76) | 0.553 | 0.82 (0.34−1.97) | 0.655 | |
| aph(3”)-Ib | aph(6)-Id | IncFIB(AP001918) | |||||
| OR (95% CI) | p-value | OR (95% CI) | p-value | OR (95% CI) | p-value | ||
| Location type | Conservation area | REF | 0.011a (global) | REF | 0.011a (global) | REF | 0.031a (global) |
| Swine farm | 2.45 (1.22−4.92) | 0.012 | 2.45 (1.22−4.92) | 0.012 | 2.07 (1.06−4.04) | 0.032 | |
| Source type | Soil | REF | 0.492b (global) | REF | 0.492b (global) | REF | 0.738a (global) |
| Wildlife | 0.78 (0.38−1.60) | 0.492 | 0.78 (0.38−1.60) | 0.492 | 0.89 (0.46−1.72) | 0.738 | |
| IncI1(1-alpha) | IncFII | ||||||
| OR (95% CI) | p-value | OR (95% CI) | p-value | ||||
| Location type | Conservation area | REF | 0.203b (global) | REF | 0.571b (global) | ||
| Swine farm | 0.39 (0.09−1.66) | 0.203 | 1.33 (0.49−3.59) | 0.573 | |||
| Source type | Soil | REF | 0.516b (global) | REF | 0.614a (global) | ||
| Wildlife | 1.36 (0.54−3.43) | 0.516 | 0.77 (0.29−2.09) | 0.615 | |||
a The random intercept for clustering by site or animal was not retained in the model, thus ordinary logistic regression was used.
b Included a random intercept for clustering at the site-level. Variance components were: tet(A) source type 0.22 (95%CI: 0.03−1.72); tet(B) source type 0.13 (95%CI: 0.00−4.63); tet(B) location type 0.16 (95%CI: 0.00−2.91); blaTEM-1 location type 0.22 (95%CI: 0.02−2.33); blaTEM-1 source type 0.24 (95% CI: 0.02−2.40); sul1 location type 0.40 (95%CI: 0.05−3.39); sul1 source type 0.41 (95%CI: 0.05−3.36); aph(3”)-Ib source type 0.32 (95%CI: 0.02−3.50); aph(6)-Id source type 0.32 (95%CI: 0.02−3.50); IncI1(1-alpha) source type 0.73 (95%CI: 0.11−4.69); IncI1(1-alpha) location type 0.63 (95%CI: 0.10−3.95).
c Adjusted for confounding by year of sampling.