Table 3.
Multivariate analysis of factors involved in a norovirus outbreak in a high school, Lleida, Spain
| Factor | Cases n (%) | Controls n (%) | cOR | 95% CI | aOR | 95% CI |
|---|---|---|---|---|---|---|
| Sex | ||||||
| Female | 25 (59·5) | 97 (57·7) | 1·1 | 0·5–2·1 | 1·1 | 0·5–2·5 |
| Male | 17 (40·5) | 71 (42·3) | 1 | 1 | 1 | |
| Age group, years | ||||||
| 10–12 | 8 (19·0) | 25 (14·9) | 6·4 | 0·7–55·5 | 5·2 | 0·6–47·6 |
| 13–15 | 26 (61·9) | 63 (37·5) | 8·2 | 1·1–64·7 | 8·3 | 1·0–67·4 |
| 16–18 | 7 (16·7) | 60 (35·7) | 2·3 | 0·3–20·1 | 5·4 | 0·6–51·6 |
| >18 | 1 (2·4) | 20 (11·9) | 1 | 1 | ||
| Close contact with patient | ||||||
| Yes | 18 (42·9) | 28 (16·7) | 3·75 | 1·8–7·8 | 1·4 | 0·5–1·4 |
| No | 24 (57·1) | 140 (83·3) | 1 | 1 | ||
| Exposure to vomit | ||||||
| Yes | 12 (28·6) | 7 (4·2) | 9·2 | 3·3–25·2 | 4·7 | 2·0–11·2 |
| No | 30 (71·4) | 161 (95·8) | 1 | 1 | ||
| Consumed food in dining room | ||||||
| Yes | 34 (80·9) | 71 (42·3) | 6·9 | 2·0–16·1 | 5·8 | 1·8–19·3 |
| No | 8 (19·1) | 97 (57·7) | 1 | 1 |
cOR, Crude odds ratio; CI, confidence interval; aOR adjusted odds ratio.