Table 4.

Conjugation frequencies of ESBL-producing E. coli according to their origin.

Origin	Conjugation Frequency Average ± Sd	Conjugation Frequency Range
Rivers and WWTPs	1.15 × 10−1 ± 5 × 10−1	2.35–3.37 × 10−6
Healthy volunteers	3.38 × 10−2 ± 4.20 × 10−2	4.81× 10−2–2.28 × 10−6
Clinical cases	2.64 × 10−3 ± 5.82 × 10−3	1.19 × 10−2–9.08 × 10−7
Farms and feeds	1.53 × 10−4 ± 2.85 × 10−4	1.03 × 10−4–9.14 × 10−7
Food products	9.61 × 10−4 ± 1.96 × 10−3	1.16 × 10−3–3.59 × 10−7