Table 2 Univariable logistic regression analysis of E .coli O157:H7 occurrence with various risk factors

Area

 Rural

120

8

0.61

–

–

–

 Urban

269

11

0.306

0.61

0.24–1.60

Breed

 Exotic

101

1

*

–

–

–

 Cross

183

13

0.059

7.17

0.93–55.65

 Local

105

5

0.155

4.81

0.55–41.89

Cleaning of pens

 No stay overnight

133

13

7.81^a

–

–

–

 Stay overnight

256

6

0.005^**

4.17

1.61–12.5

Herd size (Farm scale)

 Medium scale

137

3

2.23

–

–

–

 Small scale

252

16

0.095

2.90

0.94–12.62

Milking location

 In barn

151

13

5.43^a

–

–

–

 Anywhere

238

6

0.005^**

3.45

1.32–10.00

Hand wash

 Before and after milking

377

15

*

 Only before milking

12

4

0.000^***

8.37

2.15–27.49

Floor type

 Earthen

214

8

0.75^a

–

–

–

 Concrete

175

11

0.275

1.68

0.67–4.42

Use of towel

 No use of towel

96

8

*

–

–

–

 Before milking

174

9

0.310

0.60

0.22–1.61

 Before and after milking

138

2

0.023

0.16

0.03–0.78

Use of detergent

 No

52

2

*

–

–

–

 Yes

356

17

0.767

1.25

0.35–8.06

History of mastitis

 No

104

8

*

–

–

–

 Yes

304

11

0.096

0.45

0.18–0.19