TABLE 2.

Characterization of O157:H7 isolates from the Ganges River, Varanasi

Isolate	Sampling site	Resulta of:
		PCR for stx1	PCR for stx2	PCR for eae	Sorbitol fermentation test
Referenceb	NAc	+	+	+	−
No. 1	Nagwa Nala	+	+	+	+
No. 2	Nagwa Nala	−	−	−	+
No. 3	Tulsi Ghat	+	+	+	+
No. 4	Varuna River	+	+	+	+

^aProfiles for O157:H7 strains were determined using PCR analysis with an array of virulence gene primers. +, positive; −, negative; stx₁, Shiga toxin 1 gene; stx₂, Shiga toxin 2 gene; eae, enterocyte attachment and effacement (intimin) gene. The ability to ferment sorbitol was tested using API 20E and BBL crystal enteric/nonfermenter identification kits.

^bThe O157:H7 reference strain is from the E. coli Reference Center, Penn State University (identification no. 3A-3299-85).

^cNA, not applicable.