|
|
Research
Sporadic Cryptosporidiosis,
North Cumbria, England, 1996–2000
Stella Goh,* Mark Reacher,†
David P. Casemore,‡ Neville Q. Verlander,† Rachel Chalmers,§ Margaret
Knowles,¶ Joy Williams,* Keith Osborn,# and Sarah Richards**
*Carlisle and District Primary Care Trust, Rosehill, Carlisle, United
Kingdom; †Communicable Disease Surveillance Centre, London, United Kingdom;
‡University of Wales, Aberystwyth, Ceredigion, Wales, United Kingdom;
§Singleton Hospital, Swansea, Wales, United Kingdom; ¶Cumberland Infirmary,
Carlisle, United Kingdom; #United Utilities, Great Sankey, Warrington,
United Kingdom; and **West Cumberland Hospital, Whitehaven, United Kingdom
| Online Appendix.
Single variable analysisa |
|
|
Water and fluid consumption
|
Cases
|
Controls
|
OR
|
LCL
|
UCL
|
p value
|
|
|
Usually drink cold tap water without boiling it
first
|
|
Y
|
136
|
373
|
2.12
|
1.16
|
3.91
|
0.012
|
|
N
|
16
|
93
|
1
|
|
|
|
|
Usual daily consumption of cold unboiled tap water
at home (pints)
|
|
<¼
|
23
|
106
|
1
|
|
|
0.005b
|
|
¼–1
|
65
|
218
|
1.37
|
0.79
|
2.42
|
|
|
>1–2
|
40
|
96
|
1.92
|
1.03
|
3.59
|
|
|
>2
|
21
|
40
|
2.42
|
1.14
|
5.13
|
|
|
Usual consumption of cold, unboiled tap water away
from home (pints) at work/nursery/school in the Copeland/Allerdale
area
|
|
<¼
|
83
|
273
|
1
|
|
|
0.495b
|
|
¼–1
|
39
|
110
|
1.17
|
0.73
|
1.85
|
|
|
>1
|
2
|
5
|
1.32
|
0.17
|
7.82
|
|
|
Was usual consumption unboiled tap water away from
home/at work/nursery outside the Copeland/Allerdale area?
|
|
Y
|
13
|
31
|
1.29
|
0.62
|
2.67
|
0.573
|
|
N
|
137
|
422
|
1
|
|
|
|
|
Usual daily volume of cold, unboiled tap water drunk
(pints) at home and away from home in the Allerdale and Copeland
area
|
|
<¼
|
19
|
108
|
1
|
|
|
0.017b
|
|
¼–1
|
58
|
175
|
1.88
|
1.03
|
3.47
|
|
|
>1–2
|
45
|
121
|
2.11
|
1.12
|
4.01
|
|
|
>2
|
28
|
62
|
2.57
|
1.26
|
5.24
|
|
|
Do you usually drink bottled water?
|
|
Y
|
16
|
36
|
1.43
|
0.73
|
2.79
|
0.323
|
|
N
|
133
|
429
|
1
|
|
|
|
|
Do you usually drink soft drinks?
|
|
Y
|
87
|
283
|
0.86
|
0.58
|
1.27
|
0.467
|
|
N
|
64
|
178
|
1
|
|
|
|
|
If yes, how much soft drinks, on average, do you
drink per day (pints)
|
|
<¼
|
66
|
181
|
1
|
|
|
0.358b
|
|
¼–¾
|
36
|
110
|
0.9
|
0.55
|
1.47
|
|
|
1–2
|
31
|
103
|
0.83
|
0.49
|
1.39
|
|
|
>2
|
11
|
40
|
0.75
|
0.34
|
1.63
|
|
|
Did you have any drinks with ice added:
(cases) in the 2 weeks before illness?
(controls) in the 2 weeks before interview?
|
|
Y
|
29
|
106
|
0.83
|
0.51
|
1.36
|
0.514
|
|
N
|
116
|
354
|
1
|
|
|
|
|
If yes, consumption of ice at home:
(cases) in the 2 weeks before illness?
(controls) in the 2 weeks before interview?
|
|
Y
|
11
|
57
|
0.56
|
0.27
|
1.15
|
0.119
|
|
N
|
141
|
409
|
1
|
|
|
|
|
Drink pasteurized milk
|
|
Y
|
134
|
396
|
1.3
|
0.72
|
2.36
|
0.431
|
|
N
|
18
|
69
|
1
|
|
|
|
|
Pints of pasteurized milk on average per day (pints)
|
|
<¼
|
19
|
71
|
1
|
|
|
0.221b
|
|
¼–¾
|
66
|
153
|
1.61
|
0.87
|
3.01
|
|
|
>1
|
56
|
202
|
1.04
|
0.56
|
1.94
|
|
|
Drink unpasteurized milk
|
|
Y
|
9
|
22
|
1.28
|
0.53
|
3.02
|
0.699
|
|
N
|
142
|
443
|
1
|
|
|
|
|
|
Food consumption
|
Cases
|
Controls
|
OR
|
LCL
|
UCL
|
p value
|
|
|
Lettuce
|
|
Y
|
36
|
166
|
0.58
|
0.37
|
0.9
|
0.013
|
|
N
|
112
|
298
|
1
|
|
|
|
|
Tomatoes
|
|
Y
|
42
|
170
|
0.65
|
0.43
|
1
|
0.048
|
|
N
|
110
|
291
|
1
|
|
|
|
|
Coleslaw
|
|
Y
|
26
|
93
|
0.85
|
0.51
|
1.41
|
0.572
|
|
N
|
122
|
369
|
1
|
|
|
|
|
Mixed salad
|
|
Y
|
25
|
123
|
0.56
|
0.33
|
0.92
|
0.020
|
|
N
|
124
|
339
|
1
|
|
|
|
|
Raw sausages
|
|
Y
|
6
|
12
|
1.56
|
0.51
|
4.61
|
0.4062
|
|
N
|
145
|
452
|
1
|
|
|
|
|
Other raw meat
|
|
Y
|
8
|
13
|
1.93
|
0.71
|
5.14
|
0.233
|
|
Fresh raw vegetables
|
|
Y
|
47
|
177
|
0.76
|
0.5
|
1.16
|
0.216
|
|
N
|
100
|
288
|
1
|
|
|
|
|
Local cheese
|
|
Y
|
5
|
8
|
1.94
|
0.54
|
6.71
|
0.3252
|
|
N
|
144
|
446
|
1
|
|
|
|
|
Other cheese
|
|
Y
|
113
|
322
|
1.43
|
0.91
|
2.27
|
0.124
|
|
N
|
34
|
139
|
1
|
|
|
|
|
Yogurt
|
|
Y
|
113
|
346
|
1.03
|
0.66
|
1.63
|
0.968
|
|
N
|
37
|
117
|
1
|
|
|
|
|
Ice cream
|
|
Y
|
98
|
338
|
0.68
|
0.45
|
1.04
|
0.072
|
|
N
|
53
|
125
|
1
|
|
|
|
|
Cream
|
|
Y
|
18
|
95
|
0.53
|
0.3
|
0.95
|
0.029
|
|
N
|
131
|
369
|
1
|
|
|
|
|
|
Farm and farm animal contact
|
Cases
|
Controls
|
OR
|
LCL
|
UCL
|
p value
|
|
|
Did you have contact with farms?
|
|
Y
|
59
|
108
|
2.11
|
1.4
|
3.2
|
<0.001
|
|
N
|
91
|
352
|
1
|
|
|
|
|
Any short visit at a farm
|
|
Y
|
40
|
57
|
2.56
|
1.57
|
4.17
|
<0.001
|
|
N
|
107
|
391
|
1
|
|
|
|
|
Frequency of farm visit
|
|
0
|
91
|
352
|
1
|
|
|
0.003b
|
|
1–5
|
44
|
82
|
2.08
|
1.32
|
3.27
|
|
|
6–10
|
3
|
2
|
5.8
|
0.78
|
50.38
|
|
|
>11
|
8
|
11
|
2.81
|
1
|
7.81
|
|
|
Any contact with a dairy farm
|
|
Y
|
13
|
18
|
2.38
|
1.06
|
5.31
|
0.033
|
|
N
|
127
|
418
|
1
|
|
|
|
|
Any contact with a farm with cattle or sheep
|
|
Y
|
15
|
29
|
1.68
|
0.83
|
3.4
|
0.164
|
|
N
|
125
|
407
|
1
|
|
|
|
|
Any contact with a farm with cattle and sheep
|
|
Y
|
10
|
20
|
1.6
|
0.67
|
3.73
|
0.334
|
|
N
|
130
|
416
|
1
|
|
|
|
|
Any contact with a farm without cattle or sheep
|
|
Y
|
15
|
19
|
2.63
|
1.22
|
5.66
|
0.010
|
|
N
|
125
|
417
|
1
|
|
|
|
|
Any overnight stay at a farm
|
|
Y
|
1
|
5
|
0.61
|
0.03
|
5.45
|
1.000
|
|
N
|
146
|
443
|
1
|
|
|
|
|
Did you have contact with farm animals?
|
|
Y
|
53
|
92
|
2.23
|
1.45
|
3.43
|
<0.001
|
|
N
|
94
|
364
|
1
|
|
|
|
|
Frequency of farm animal contact
|
|
0
|
94
|
364
|
1
|
|
|
|
|
1 to 20
|
38
|
68
|
2.16
|
1.34
|
3.5
|
0.051
|
|
>20
|
4
|
5
|
3.1
|
0.68
|
13.6
|
|
|
Eat food within 1 to 2 hours of contact
|
|
Y
|
32
|
41
|
3.11
|
1.79
|
5.38
|
<0.001
|
|
N
|
96
|
382
|
1
|
|
|
|
|
Did you feed farm animals by hand?
|
|
Y
|
23
|
45
|
1.74
|
0.97
|
3.12
|
0.061
|
|
N
|
116
|
396
|
1
|
|
|
|
|
Stroke any farm animal
|
|
Y
|
29
|
49
|
2.01
|
1.17
|
3.42
|
0.009
|
|
N
|
123
|
417
|
1
|
|
|
|
|
Any other contact with a farm animal
|
|
Y
|
28
|
35
|
2.78
|
1.57
|
4.93
|
<0.001
|
|
N
|
124
|
431
|
1
|
|
|
|
|
Did you have any contact with fields recently sprayed
with slurry
|
|
Y
|
5
|
10
|
1.72
|
0.5
|
5.64
|
0.351
|
|
N
|
123
|
422
|
1
|
|
|
|
|
Walk close to slurry in a field
|
|
Y
|
6
|
9
|
2.31
|
0.71
|
7.34
|
0.122
|
|
N
|
122
|
423
|
1
|
|
|
|
|
Any contact with slurry
|
|
Y
|
16
|
28
|
2
|
0.99
|
4.02
|
0.052
|
|
N
|
116
|
406
|
1
|
|
|
|
|
Contact with pet animals at home
|
|
Y
|
98
|
293
|
1.08
|
0.72
|
1.62
|
0.77
|
|
N
|
53
|
171
|
1
|
|
|
|
|
Contact with pets with diarrhea
|
|
Y
|
6
|
23
|
0.78
|
0.27
|
2.12
|
0.763
|
|
N
|
85
|
254
|
1
|
|
|
|
|
Feed your pet raw meat
|
|
Y
|
0
|
2
|
0
|
0
|
12.74
|
1.000
|
|
N
|
152
|
464
|
1
|
|
|
|
|
Feed your pet tinned meat
|
|
Y
|
42
|
126
|
1.03
|
0.67
|
1.59
|
0.97
|
|
N
|
110
|
340
|
1
|
|
|
|
|
Feed your pet pellets
|
|
Y
|
2
|
6
|
1.02
|
0
|
5.73
|
1.000
|
|
N
|
150
|
460
|
1
|
|
|
|
|
Feed your pet biscuits
|
|
Y
|
21
|
39
|
1.76
|
0.95
|
3.21
|
0.070
|
|
N
|
131
|
427
|
1
|
|
|
|
|
Feed your pet leftovers
|
|
Y
|
6
|
5
|
3.79
|
1
|
14.69
|
0.031
|
|
N
|
146
|
461
|
1
|
|
|
|
|
Feed your pet raw vegetables
|
|
Y
|
13
|
20
|
2.09
|
0.95
|
4.56
|
0.069
|
|
N
|
139
|
446
|
|
|
|
|
|
Feed your pet other food
|
|
Y
|
44
|
127
|
1.09
|
0.71
|
1.67
|
0.763
|
|
N
|
108
|
339
|
1
|
|
|
|
|
Did you have contact with any other animals or birds
|
|
Y
|
75
|
248
|
0.84
|
0.54
|
1.30
|
0.475
|
|
N
|
51
|
142
|
1
|
|
|
|
|
Did you or your child accidentally touch any dirt
or feces from any animal
|
|
Y
|
13
|
17
|
3.04
|
1.33
|
6.94
|
0.006
|
|
N
|
89
|
354
|
1
|
|
|
|
|
|
Play groups and recreational water exposure
|
Cases
|
Controls
|
OR
|
LCL
|
UCL
|
p value
|
|
|
Contact with play group
|
|
Y
|
61
|
164
|
1.27
|
0.84
|
1.9
|
0.269
|
|
N
|
82
|
279
|
1
|
|
|
|
|
Swim at a swimming pool
|
|
Y
|
44
|
141
|
0.94
|
0.61
|
1.44
|
0.838
|
|
N
|
108
|
325
|
1
|
|
|
|
|
Engage in water sports
|
|
Y
|
2
|
18
|
0.33
|
0.05
|
1.53
|
0.1852
|
|
N
|
150
|
448
|
1
|
|
|
|
|
Go paddling
|
|
Y
|
22
|
57
|
1.23
|
0.7
|
2.17
|
0.531
|
|
N
|
128
|
408
|
1
|
|
|
|
|
Any other contact with fresh water
|
|
Y
|
16
|
39
|
1.29
|
0.66
|
2.49
|
0.516
|
|
N
|
133
|
418
|
1
|
|
|
|
|
| aOR, odds ratio;
LCL, lower confidence limit; UCL, upper confidence limit. |
| bχ2
test for trend. |
|
