TABLE 1.

The occurrence of microbial source tracking markers and pathogens prior to CTD intervention during years 2005 to 2006 of the study

Microbial targeta	% of samples positive for microbial targetb								n
	CTDD	CTDU	UCTDD	UCTDU	CTDD − UCTDD	CTDD − UCTDU	CTDU − UCTDD	CTDU − UCTDU	CTDD	CTDU	UCTDD	UCTDU
Total Bacteroidales	100	100	LD	88	LDc	12	LD	12	29	21	LD	25
Bacteroidales markers
Human	7	0	LD	4	LD	3	LD	−4	29	21	LD	25
Pig	3	0	LD	0	LD	3	LD	0	29	21	LD	25
Ruminant	10	19	LD	12	LD	−2	LD	7	29	21	LD	25
Muskrat	3	14	LD	16	LD	−13	LD	−2	29	21	LD	25
Canada goose	7	0	LD	0	LD	7	LD	0	29	21	LD	25
Livestock	14	19	LD	12	LD	2	LD	7	29	21	LD	25
Wildlife	10	14	LD	16	LD	−6	LD	−2	29	21	LD	25
Other bacteria
Listeria spp.	89	100	94	100	−5	−11	6	0	18	16	17	15
Listeria monocytogenes	33	19	12	13	21	20	7	6	18	16	17	15
Salmonella spp.	6	9	9	13	−3	−7	0	−4	35	32	33	31
Campylobacter spp.	31	31	24	35	7	−4	7	−4	35	32	33	31
E. coli O157:H7	0	0	0	0	0	0	0	0	35	32	33	31

^aViral pathogens and coliphages were not collected in this period. “Livestock” and “Wildlife” are summary classes: “Livestock” represents pigs and/or ruminants, and “Wildlife” represents muskrats and/or Canada geese.

^bNo significant differences between site pairwise comparisons were observed using Fisher's exact test (significant at P < 0.05). Note that there were percentage point differences for most CTD site − UCTD site percentage point values shown. Negative values indicate the occurrence of a greater percentage in UCTD versus pre-CTD by the indicated percentage point value and site comparison.

^cLD, limited data.