Table. Relative risks for tuberculin skin-test conversion based on answers reported on employee exposure questionnaires^a.

Characteristics reported in questionnaire	Convertersb (%)	TST-negativesc (%)	Risk ratio (95% CI)	p value
Male	13 (87)	112 (45)	7.3 (1.7 to 31.9)	0.002
Ethnicity
Hispanic	10 (67)	109 (44)	2.4 (0.8 to 6.8)	0.092
White	2 (13)	105 (43)d	0.2 (0.1 to 1.0)	0.025
Black	2 (13)	22 (9)	1.5 (0.4 to 6.3)	0.41
Asian	1 (7)	9 (4)	1.8 (0.3 to 12.3)	0.45
U.S.-born	11 (73)	226 (90)	0.4 (0.1 to 1.0)	0.052
BCG vaccine history	0 (0)	15 (7)e	0.0 (0.0 to 6.0)f	0.40
Contact with any animal	7 (50)g	147 (60) h	0.7 (0.2 to 1.9)	0.45
Job type
Animal care	4 (29) g	91 (37) i	0.7 (0.2 to 2.2)	0.54
Groundskeeping	5 (36) g	14 (6)	7.1 (2.6 to 19.1)	<0.001
Custodial	2 (14) g	19 (8)	1.9 (0.5 to 8.0)	0.31
Maintenance	1 (7)	15 (6)	1.2 (0.2 to 8.5)	0.60
Construction	1 (7)	11 (4)	1.6 (0.2 to11.3)	0.49
Administrative	1 (7)	67 (27)	0.2 (0.0 to 1.7)	0.082
Animal health center exposure	5 (33)	152 (63) j	0.3 (0.1 to 0.9)	0.025
Elephant compound exposure	5 (33)	130 (52)	0.5 (0.2 to 1.4)	0.17
Trained elephants	3 (20)	12 (5)	4.1 (1.3 to 13.1)	0.045
Visited elephants	2 (13)	77 (31)	0.4 (0.1 to 1.6)	0.12
Attended necropsy	3 (20)	7 (3)	6.3 (2.1 to 18.9)	0.014
Goat compound exposure	3 (20)	72 (29)	0.6 (0.2 to 2.2)	0.35
Rhino compound exposure	2 (13)	82 (33)	0.3 (0.1 to 1.5)	0.097
Animal nursery exposure	2 (13)	124 (50) i	0.2 (0.0 to 0.7)	0.007

^aTST, tuberculin skin test; CI, confidence interval.
^bEmployee with a positive TST in any of the converter categories as described (true, probable, or possible). N=15, except where noted.
^cN=251, except where noted.
^dN=245.
^eN=232.
^fOdds ratio reported because of a zero value.
^gN=14.
^hN=244.
ⁱN=248.
^jN=243.