. Author manuscript; available in PMC: 2022 Jan 1.

Published in final edited form as: J Food Prot. 2021 Jan 1;84(1):113–121. doi: 10.4315/JFP-20-179

Table 3.

Diversity of Listeria monocytogenes sigB allelic types and pulsotypes in agricultural water and fecal samples.

Sample Type	Location	No. of L. monocytogenes	Subtyping Method^a	No. of Subtypes	Estimated Subtype Richness (95% CI)^b,c	Simpson’s Index (95% CI)^c	Effective No. of Subtype^d
Fecal	-	22	AT	5	5 (5, 8)	0.63 (0.46, 0.80)	3
	Near Pond	13	PT	7	9 (7, 33)	0.78 (0.63, 0.93)	5
Water	-	64	AT	7	7 (7, 8)	0.54 (0.41, 0.68)	2
	Stream	33	AT	6	9 (6, 73)	0.41 (0.20, 0.62)	2
	Pond	31	AT	7	8 (7, 15)	0.66 (0.49, 0.82)	3
	Pond	31	PT	19	29 (19, 207)	0.93 (0.91, 0.95)	15

AT = allelic type; PT = PFGE type. PFGE was only performed on Listeria monocytogenes isolates and not on non-pathogenic Listeria species isolates.

Estimated using weighted linear regression

95% CI: 95% confidence interval

The effective number of subtype is calculated based on Simpson’s Index of Diversity.