Table 5.

In vitro and meat BIM isolation and determination of BIM frequency.

Source of BIMs	Presumptive BIMs tested	Confirmed BIMs (%)	BIM frequency (mean ± SD)a
Secondary culture	8 EPEC	6 (75.0)	EPEC/DT1 = 8.7 × 10−7± 3.9 × 10−8
			EPEC/DT6 = 6.5 × 10−7 ± 4.8 × 10−8
Meat	8 O157:H7	2 (25.0)	O157:H7 STEC/DT1 = 1.8 × 10−6 ± 1.5 × 10−7
	STEC		O157:H7 STEC/DT6 = 1.3 × 10−6 ± 9.4 × 10−7

^aSD, standard deviation. Means and SD were calculated from duplicate experiments.

EPEC, enteropathogenic E. coli; O157:H7 STEC: O157:H7 Shigatoxigenic E. coli.