TABLE 5.

Concentrations of E. coli O157:H7 detected in environmental samples by real-time PCR

Sitea	Result (CFU ml−1) for gene and month
	stx1					stx2
	February	April	July	August	September	February	April
Raw	1.3 × 105 ± 3.2 × 104	4.9 × 104 ± 1.1 × 103	1.5 × 104 ± 5.1 × 103	1.1 × 104 ± 4.4 × 103	8.1 × 103 ± 2.2 × 103	NDb	2.2 × 104 ± 3.2 × 103
Pond	2.3 × 103 ± 1.5 × 102	7.4 × 104 ± 2.1 × 103	1.1 × 103 ± 5.6 × 102	1.7 × 104 ± 7.1 × 103	1.9 × 104 ± 6.2 × 103	ND	2.2 × 104 ± 2.2 × 104
W1 Inf	4.1 × 103 ± 3.2 × 103	1.1 × 105 ± 3.4 × 104	3.1 × 103 ± 4.1 × 103	3.3 × 104 ± 5.2 × 103	3.4 × 104 ± 2.2 × 103	1.7 × 104 ± 1.1 × 102	4.4 × 103 ± 3.1 × 103
W1 Eff	3.2 × 103 ± 3.0 × 103	5.3 × 103 ± 4.2 × 103	3.4 × 102 ± 3.0 × 103	8.3 × 103 ± 2.2 × 103	1.0 × 104 ± 1.2 × 103	ND	ND
W2 Inf	ND	8.0 × 104 ± 1.5 × 104	2.3 × 103 ± 8.2 × 102	4.1 × 104 ± 6.2 × 103	5.0 × 103 ± 6.2 × 103	ND	3.2 × 104 ± 3.3 × 104
W2 Eff	ND	7.6 × 103 ± 2.3 × 103	1.8 × 103 ± 4.2 × 102	1.2 × 104 ± 9.1 × 104	4.3 × 103 ± 6.1 × 102	ND	ND
Calf feces	1.2 × 104 ± 2.2 × 103	5.9 × 103 ± 5.2 × 103	4.8 × 103 ± 3.8 × 103	2.9 × 104 ± 2.2 × 103	6.0 × 103 ± 8.3 × 103	ND	4.9 × 103 ± 3.5 × 103
Cow feces	ND	2.7 × 105 ± 1.1 × 105	3.2 × 103 ± 2.2 × 103	1.6 × 104 ± 1.1 × 103	4.2 × 104 ± 6.3 × 103	ND	6.5 × 104 ± 3.6 × 104
Manure	4.5 × 103 ± 4.2 × 102	NAc	ND	2.7 × 104 ± 9.1 × 103	9.5 × 104 ± 5.2 × 103	1.2 × 102 ± 2.2 × 101	NA

^aAll solid samples were from calf feces (Calf F), cow feces (Cow F), or manure, and the liquid waste samples were from the facultative pond (Pond), the raw pond (Raw), wetland 1 effluent (W1 Eff), wetland 1 influent (W1 Inf), wetland 2 effluent (W2 Eff), and wetland 2 influent (W2 Inf).

^bND, not determined.

^cNA, samples not collected for analysis.