Table 5.
Variables significantly associated with positive serology for Leptospira spp. on univariate and multivariable analyses for serovar LT 1163*
| Risk factors | No. in category | No. with antibodies | Seroprevalence (%) | Univariate OR (95% CI) | Multivariable OR (95% CI) |
|---|---|---|---|---|---|
| Questionnaire variables† | |||||
| Total sampled | 807 | 26 | 3.2% | ||
| Male | 423 | 19 | 4.5% | 2.51 (1.04–6.03) | |
| Drink village water | 139 | 8 | 5.8% | 2.18 (0.93–5.13) | 2.68 (1.06–6.76) |
| Cats on home property | 404 | 18 | 4.5% | 2.27 (0.97–5.28) | 2.52 (1.03–6.21) |
| Flooding | |||||
| Flooding at work | 72 | 8 | 11.1% | 4.6 (1.45–14.57) | 3.76 (1.07–13.25) |
| Flooding on home property | 333 | 16 | 4.8% | 2.33 (1.04–5.20) | |
| Number of floods on home property: | |||||
| Nil | 472 | 10 | 2.1% | 1 | 1 |
| 1 to 2 times | 123 | 10 | 8.1% | 4.09 (1.66–10.06) | 4.01 (1.51–10.61) |
| 3 to 5 times | 58 | 3 | 5.2% | 2.52 (0.67–9.43) | 1.97 (0.50–7.87) |
| More than 5 times | 147 | 3 | 2.0% | 0.96 (0.26–3.54) | 0.55 (0.14–2.22) |
| Swimming at beach | |||||
| Never | 269 | 3 | 1.1% | 1 | 1 |
| Occasional (< once a week) | 295 | 8 | 2.7% | 2.47 (0.65–9.41) | 2.50 (0.64–9.81) |
| Frequent (> once a week) | 230 | 14 | 6.1% | 5.75 (1.63–20.26) | 5.32 (1.47–19.31) |
| Swimming in river | |||||
| Never | 680 | 20 | 2.9% | 1 | |
| Occasional (< once a week) | 82 | 1 | 1.2% | 0.41 (0.05–3.08) | |
| Frequent (> once a week) | 30 | 4 | 13.3% | 5.08 (1.62–15.92) | |
| Kayaking | |||||
| Never | 742 | 34 | 4.6% | 1 | |
| Occasional (< once a week) | 27 | 0 | 0.0% | no cases | |
| Frequent (> once a week) | 24 | 3 | 12.5% | 4.68 (1.30–16.85) | |
| Camping | |||||
| Never | 704 | 21 | 3.0% | 1 | |
| Occasional (< once a week) | 62 | 1 | 1.6% | 0.53 (0.07–4.03) | |
| Frequent (> once a week) | 27 | 3 | 11.1% | 4.07 (1.13–14.57) | |
| Environmental variablesठ| |||||
| Total sampled | 721 | 25 | 3.5% | ||
| House less than 50 m from stream | 260 | 14 | 5.4% | 2.32 (1.04–5.21) | |
| Piggeries within 250 m and above house | |||||
| 0–2 piggeries | 370 | 9 | 2.4% | 1 | 1 |
| 3–5 piggeries | 239 | 4 | 1.7% | 0.68 (0.21–2.24) | 0.67 (0.20–2.24) |
| > 5 piggeries | 112 | 12 | 10.7% | 4.81 (1.97–11.75) | 3.32 (1.29–8.54) |
| House in lowest 25th centile of altitude in village | |||||
| No | 606 | 16 | 2.6% | 1 | 1 |
| Yes | 115 | 9 | 7.8% | 3.13 (1.34–7.27) | 2.80 (1.12–6.97) |
*
Statistically significant odds ratios (ORs) are shown in bold.
†
Participants from all islands.
‡
Participants from Tutuila only.
§
Variables included in multivariable model: drink village water, swim at beach, piggeries, and house below 25th centile of altitude.
CI = confidence interval.