TABLE 1.

Distribution of environmental samples across surface categories and production departments

Production department and parametera	Result by surface category
	Floor and drainage	Operator	Equipment	Total
Ham production
No. of samples	94	74	216	384
No. of positives	9	7	9	25
% prevalence (95% CI)	9.6 (5.1–17.2)	9.5 (4.7–18.3)	4.2 (2.2–7.7)	6.5 (4.4–9.4)
Deboning
No. of samples	127	171	414	712
No. of positives	30	20	22	72
% prevalence (95% CI)	23.6 (17.1–31.7)	11.7 (7.7–17.4)	5.3 (3.5–7.9)	10.1 (8.1–12.5)
Slicing
No. of samples	74	75	223	372
No. of positives	4	3	4	11
% prevalence (95% CI)	5.4 (2.1–1.31)	4.0 (1.4–11.1)	1.8 (0.7–4.5)	3.0 (1.7–5.2)

^aCI, confidence interval.