Table 2.

Association of exposures with case status, Community A, Missouri, June 1–December 17, 2013

Risk factor	Exposed			Unexposed			Relative risk (95% CI)
	Cases no.	Total no.	%	Cases no.	Total no.	%
Job description*
Cow dairy	12	25	48	35	76	46	1.0 (0.6, 1.7)
Goat dairy	6	7	86	41	94	44	2.0 (1.3, 2.9)
Construction	3	9	33	44	92	48	0.7 (0.3, 1.8)
Environmental†	8	10	80	39	91	43	1.9 (1.3, 2.8)
Food services	6	8	75	41	93	44	1.7 (1.1, 2.7)
Education/management/administration	6	19	32	41	82	50	0.6 (0.3, 1.3)
Student	3	11	27	44	90	49	0.6 (0.2, 1.5)
Goat interactions‡
Goat contact or close proximity	28	44	64	19	57	33	1.9 (1.2, 2.9)
Milking	4	4	100	43	97	44	2.3 (1.8, 2.8)
Feeding/watering	5	5	100	42	96	44	2.3 (1.8, 2.9)
Cleaning holding areas	6	6	100	41	95	43	2.3 (1.8, 2.9)
Removing/handling manure	10	11	91	37	90	41	2.2 (1.6, 3.0)
Replacing bedding	4	4	100	43	97	44	2.3 (1.8, 2.8)
Veterinary care	4	4	100	43	97	44	2.3 (1.8, 2.8)
Help with or observe a birth	4	4	100	43	97	44	2.3 (1.8, 2.8)
Direct contact with newborn kid	4	5	80	43	96	45	1.8 (1.1, 2.9)
Direct contact with dead goat	5	5	100	42	96	44	2.3 (1.8, 2.9)
Direct contact with birth products	6	6	100	41	95	43	2.3 (1.8, 2.9)
Cow interactions‡
Cow contact or close proximity	28	50	56	19	51	37	1.5 (1.0, 2.3)
Milking	10	21	48	33	73	45	1.1 (0.6, 1.8)
Feeding/watering	9	14	64	38	86	44	1.5 (0.9, 2.3)
Cleaning holding areas	15	24	63	32	76	42	1.5 (1.0, 2.2)
Removing/handling manure	20	32	63	27	68	40	1.6 (1.1, 2.3)
Replacing bedding	11	15	73	36	85	42	1.7 (1.2, 2.6)
Veterinary care	10	11	91	37	89	42	2.2 (1.6, 3.0)
Help with or observe a birth	9	9	100	38	90	42	2.4 (1.9, 3.0)
Direct contact with newborn calf	11	16	69	36	84	43	1.6 (1.1, 2.4)
Direct contact with dead cow	12	15	80	35	85	41	1.9 (1.4, 2.8)
Direct contact with birth products	13	15	87	34	85	40	2.2 (1.6, 3.0)
Other goat and cow exposures
Known exposure to:
Animal that had an abortion or stillbirth§	13	17	76	34	84	40	1.9 (1.3, 2.7)
Animal that had newborn death§	15	19	79	32	82	39	2.0 (1.4, 2.9)
Animal that had weak newborn§	15	20	75	32	81	40	1.9 (1.3, 2.7)
Dispose of animal carcasses	14	21	67	33	79	42	1.6 (1.1, 2.4)
Clean animal holding areas	18	28	64	29	73	40	1.6 (1.1, 2.4)
Clean animal holding areas after birthing	7	9	78	40	92	43	1.8 (1.2, 2.7)
Contact or work with ruminant excreta	25	38	66	22	63	35	1.9 (1.3, 2.8)
Contact or close proximity with ruminants∥	40	69	58	7	32	22	2.7 (1.3, 5.3)
Household exposures
Household member with cow or goat contact∥ (among those with no personal exposure)	5	6	45	2	19	10	4.8 (1.1, 20.7)
Work boots brought into home	12	13	92	19	41	46	2.0 (1.4, 2.9)
Work clothing laundered at home	17	25	68	20	36	56	1.2 (0.8, 1.8)
Miscellaneous exposures
Consume raw dairy products	9	14	64	38	87	44	1.5 (0.9, 2.3)
Consume pasteurized goat cheese	23	42	55	24	56	43	1.3 (0.8, 1.9)

CI = confidence interval.

^*More than one job may have been reported in the past 6 months; only jobs reported by ≥ 5 persons were analyzed.

^†Includes work with animal waste, compost management, land application of compost, and spray irrigation from manure lagoons.

^‡Ordinal independent variables describing frequency were dichotomized to ‘never or hardly ever' and ‘daily, several times per week or several times per month'.

^§Answers of “don't know” or “not applicable” classified as “no” for analysis.

^∥Contact includes work with ruminant excreta.