Table 1.
Description of cases and controls and univariate analysis results
| Cases | Controls | Wald chi-square | |||||
|---|---|---|---|---|---|---|---|
| n/N | % | n/N | % | p-value | mORa | 95 % Wald CI | |
| Waterborne routes of exposure | |||||||
| Drinking water source = private well | 12/85 | 14 | 12/170 | 7 | 0.08 | 2.1 | 0.91–4.7 |
| Drinking water source = municipal water | 55/85 | 65 | 125/170 | 74 | 0.15 | 0.67 | 0.38–1.2 |
| Drinking water source = bottled water | 38/85 | 45 | 99/170 | 58 | 0.042 | 0.58 | 0.34–0.98 |
| Use any in home treatment | 33/81 | 41 | 78/170 | 46 | 0.44 | 0.81 | 0.47–1.4 |
| Use tap filter | 15/85 | 18 | 11/170 | 6 | 0.007 | 3.1 | 1.3–7.1 |
| Drink untreated or raw water | 11/76 | 14 | 6/169 | 4 | 0.004 | 4.6 | 1.6–13.0 |
| Swim in or go into any natural water | 11/85 | 13 | 11/170 | 6 | 0.082 | 2.3 | 0.90–5.8 |
| Swim or go into any artificial water | 14/85 | 16 | 48/170 | 28 | 0.027 | 0.43 | 0.20–0.91 |
| Environmental exposures | |||||||
| Go canoeing, kayaking, hiking or camping | 6/84 | 7 | 15/170 | 9 | 0.64 | 0.79 | 0.30–2.1 |
| Live on a farm or country property | 10/84 | 12 | 9/170 | 5 | 0.068 | 2.5 | 0.94–6.7 |
| Live with contact with food animals | 6/85 | 7 | 5/170 | 3 | 0.15 | 2.4 | 0.73–7.9 |
| Visit a farm or country property | 14/85 | 16 | 24/170 | 14 | 0.60 | 1.2 | 0.58–2.6 |
| Visit farm or country property and contact with food animals | 8/85 | 9 | 18/170 | 11 | 0.75 | 0.86 | 0.33–2.2 |
| Contact with households pets | 52/84 | 62 | 121/170 | 71 | 0.12 | 0.64 | 0.36–1.1 |
| Contact with cat | 19/85 | 22 | 67/170 | 39 | 0.008 | 0.45 | 0.25–0.82 |
| Contact with dog | 44/85 | 52 | 89/169 | 53 | 0.89 | 0.97 | 0.58–1.6 |
| Contact with pets other than cats and dogs | 4/85 | 5 | 24/170 | 14 | 0.025 | 0.28 | 0.09–0.85 |
| Gardening | 12/83 | 14 | 59/170 | 35 | 0.0007 | 0.29 | 0.14–0.59 |
| Social events and domestic travel | |||||||
| Attend a barbeque | 25/82 | 30 | 84/170 | 49 | 0.005 | 0.42 | 0.23–0.77 |
| Attend social gathering | 17/83 | 20 | 63/170 | 37 | 0.016 | 0.46 | 0.25–0.87 |
| Travel outside the region but within Canada | 8/85 | 9 | 34/170 | 20 | 0.031 | 0.39 | 0.16–0.92 |
| Food purchasing behaviours | |||||||
| Shop for food in supermarket | 78/81 | 96 | 165/170 | 97 | 0.79 | 0.81 | 0.17–3.8 |
| Shop for food in farmers market | 7/81 | 9 | 51/170 | 30 | 0.0005 | 0.23 | 0.10–0.52 |
| Shop for food in butcher shop | 6/81 | 7 | 34/170 | 20 | 0.016 | 0.33 | 0.13–0.81 |
| Shop for food in farm laneway, farm stand | 3/81 | 4 | 14/170 | 8 | 0.16 | 0.39 | 0.11–1.4 |
| Shop for food from other location | 4/81 | 5 | 6/170 | 4 | 0.74 | 1.2 | 0.35–4.4 |
| Meat purchasing behaviours | |||||||
| Eat meat purchased from another place than grocery store | 13/85 | 15 | 43/169 | 25 | 0.084 | 0.55 | 0.27–1.1 |
| Consume meat from hunting | 1/85 | 1 | 6/168 | 4 | 0.31 | 0.33 | 0.04–2.8 |
| Consume meat from butcher | 7/85 | 8 | 31/169 | 18 | 0.042 | 0.41 | 0.17–0.97 |
| Consume meat from kill | 4/85 | 5 | 11/169 | 7 | 0.57 | 0.71 | 0.22–2.3 |
| Food outside home | |||||||
| Eat food prepared outside the home | 45/76 | 59 | 135/169 | 80 | 0.001 | 0.36 | 0.19–0.67 |
| Food from fast food chain restaurant | 19/85 | 22 | 86/168 | 51 | <0.0001 | 0.26 | 0.14–0.50 |
| Food from eat-in restaurant | 26/85 | 31 | 88/169 | 52 | 0.002 | 0.41 | 0.23–0.72 |
| Food from eat-in cafeteria | 2/85 | 2 | 14/169 | 8 | 0.087 | 0.27 | 0.06–1.2 |
| Food from deli | 1/85 | 1 | 14/160 | 9 | 0.052 | 0.13 | 0.02–1.0 |
| Food from ready-to-eat | 5/85 | 6 | 55/169 | 33 | <0.0001 | 0.12 | 0.04–0.34 |
| Food from food vendor | 3/85 | 4 | 17/169 | 10 | 0.08 | 0.32 | 0.09–1.1 |
| High risk foods | |||||||
| Consume undercooked food | 8/85 | 9 | 24/169 | 14 | 0.30 | 0.64 | 0.28–1.5 |
| Consume spoiled food | 9/84 | 11 | 14/169 | 8 | 0.54 | 1.3 | 0.55–3.2 |
| Consume unpasteurized products (dairy, juice, milk) | 5/84 | 6 | 18/169 | 11 | 0.28 | 0.58 | 0.21–1.6 |
| High risk occupations | |||||||
| Agriculture/food and animal processing | 2/85 | 2 | 3/170 | 2 | 0.75 | 1.3 | 0.22–8.0 |
| Food preparation | 4/85 | 5 | 3/170 | 2 | 0.17 | 3.3 | 0.59–19 |
| Daycare | 2/85 | 2 | 4/170 | 2 | Not converged | ||
| Healthcare | 3/85 | 4 | 5/170 | 3 | 0.80 | 1.2 | 0.29–5.0 |
| Gender | |||||||
| Male | 45/85 | 53 | 72/170 | 42 | 0.08 | 1.7 | 0.94–3.1 |
aMatched odd ratio, bold indicates significant association (p < 0.05)