Table 1.
Multivariate logistic regression model showing risk factors for sporadic cases of STEC infections in New Zealand
| Variable | Coefficient (SE)a | Adjusted odds ratio (95% CI)b | p-valuec | |
|---|---|---|---|---|
| Other household member having contact with animals other than household petsd* |
|
|
|
|
| for 0–4 year-old |
1.39 (0.42) |
4.03 (1.78–9.13) |
0.001 |
|
| for 5–19 year-old |
-0.77 (0.67) |
0.47 (0.13–1.72) |
0.251 |
|
| for >19 year-old |
0.30 (0.49) |
1.35 (0.51–3.56) |
0.541 |
|
| Cattle livestock present in meshblock |
0.64 (0.30) |
1.89 (1.04–3.42) |
0.037 |
|
| Contact with animal manure |
0.74 (0.32) |
2.09 (1.12–3.90) |
0.021 |
|
| Contact with recreational waters |
1.08 (0.42) |
2.95 (1.30–6.70) |
0.010 |
|
| Travelled to areas in New Zealand with interrupted or no main water supply |
0.89 (0.43) |
2.43 (1.04–5.65) |
0.040 |
|
| Handling raw offal |
-0.94 (0.35) |
0.39 (0.20–0.78) |
0.008 |
|
| Drinking refrigerated fruit juice from supermarket |
-1.37 (0.32) |
0.25 (0.14–0.47) |
<0.001 |
|
| Visiting childcare/kindergarten/or school |
-0.92 (0.31) |
0.40 (0.22–0.73) |
0.003 |
|
| Eating raw vegetables |
-0.65 (0.33) |
0.52 (0.27–0.99) |
0.046 |
|
| Eating seafood |
-0.52 (0.27) |
0.59 (0.35–1.02) |
0.057 |
|
| Dining outside home |
-0.44 (0.29) |
0.65 (0.37–1.14) |
0.133 |
|
| Water supply to home from private bore/spring/creek/or stream |
0.62 (0.39) |
1.85 (0.86–4.00) |
0.117 |
|
| Contact with children wearing nappies |
-0.33 (0.31) |
0.72 (0.39–1.33) |
0.298 |
|
| Taking antacids | -0.84 (0.58) | 0.43 (0.14–1.34) | 0.147 | |
Likelihood ratio test = 153.70 (df = 18, p < 0.001).
aStandard error.
b95% confidence interval.
cp-values were computed based on 50 imputations.
dThis variable was modelled using a multiplicative interaction term comprising the variables 'Other household member having contact with animals other than household pets’ and 'Age’.
It can be interpreted as follows: a child 0–4 years of age is at significantly higher risk of being an STEC case, if another household member had contact with animals other than household pets, compared to a child of the same age without this risk factor.
*p-value = 0.064 for the variable 'Other household member having contact with animals other than household pets’ without the interaction term.