Table 2.
Factors associated with Schistosoma mansoni infection
| Risk factor |
S. mansoni positive Proportion (%) |
Crude odds ratio† (95% CI) |
P-value‡ (trend) | Adjusted odds ratio† (95% CI) |
P-value‡ (trend) |
|---|---|---|---|---|---|
| Gender | |||||
| Female | 216/537 (40.7) | 1 | <0.001 | 1 | <0.001 |
| Male | 503/720 (68.7) | 3.26 (2.39–4.45) | 2.62 (1.88–3.65) | ||
| Age group | |||||
| 13–19 | 78/120 (65.7) | 1 | 0.48 (0.14) | 1 | 0.056 (0.007) |
| 20–29 | 311/523 (59.2) | 0.75 (0.39–1.44) | 0.58 (0.36–0.95) | ||
| 30–39 | 206/383 (53.8) | 0.60 (0.28–1.30) | 0.38 (0.19–0.78) | ||
| 40+ | 123/227 (53.1) | 0.59 (0.25–1.40) | 0.31 (0.14–0.68) | ||
| Occupation | |||||
| Housewife | 38/97 (39.2) | 1 | 0.001 | 1 | 0.059 |
| Fishing | 440/642 (68.5) | 3.24 (1.92–5.45) | 1.85 (1.00–3.44) | ||
| Shops, saloons | 41/95 (43.2) | 1.30 (0.65–2.59) | 0.96 (0.43–2.13) | ||
| Bars, restaurants | 38/117 (32.5) | 0.63 (0.35–1.15) | 0.62 (0.33–1.17) | ||
| Agriculture/charcoal | 107/209 (51.2) | 1.72 (0.93–3.16) | 1.01 (0.47–2.18) | ||
| Other | 47/86 (33.3) | 1.24 (0.60–2.57) | 0.64 (0.27–1.52) | ||
| Asset score | 0.94 (0.88–1.01) | 0.11 | 1.05 (0.95–1.15) | 0.31 | |
| Anybody smoking in house | |||||
| No | 493/891 (55.0) | 1 | 0.022 | 1 | 0.83 |
| Yes | 226/366 (62.2) | 1.35 (1.05–1.75) | 0.98 (0.81–1.18) | ||
| Cooking with charcoal | |||||
| No | 118/189 (67.7) | 1 | 0.044 | 1 | 0.41 |
| Yes | 601/1068 (55.3) | 0.60 (0.36–0.98) | 0.80 (0.45–1.39) | ||
| Source of water for domestic use | |||||
| Lake | 671/1257 (57.8) | 1 | 0.086 | 1 | 0.058 |
| Spring | 3/16 (16.8) | 0.15 (0.03–0.66) | 0.17 (0.04–0.78) | ||
| Well | 5/9 (55.5) | 0.91 (0.28–2.94) | 0.44 (0.14–1.43) | ||
| Communal tap | 40/74 (57.2) | 0.98 (0.63–1.52) | 1.10 (0.48–2.52) | ||
| How often do you go in the lake? | |||||
| Every day | 530/907 (58.4) | 1 | <0.001 (0.009) | 1 | 0.005 (0.43) |
| Almost every day | 135/206 (65.5) | 1.45 (1.02–2.06) | 1.66 (1.01–2.74) | ||
| Weekly | 35/74 (47.3) | 0.58 (0.27–1.23) | 0.82 (0.33–2.02) | ||
| Less frequently | 14/63 (22.2) | 0.20 (0.11–0.38) | 0.39 (0.15–1.01) | ||
| When you are outside the house, what do you normally wear on your feet? | |||||
| Nothing | 30/43 (75.0) | 1 | 0.062 | 1 | 0.004 |
| Sandals | 644/1146 (55.8) | 0.42 (0.19–0.93) | 0.29 (0.15–0.57) | ||
| Closed shoes | 40/60 (65.7) | 0.64 (0.25–1.74) | 0.29 (0.11–0.76) | ||
| Have you ever been treated for worms? | |||||
| No | 306/472 (64.6) | 1 | 0.011 | 1 | 0.031 |
| Yes | 399/768 (52.0) | 0.61 (0.42–0.88) | 0.56 (0.34–0.94) | ||
CI, confidence interval.
†
Odds ratios estimated using logistic regression models with linearised standard errors and weighting to allow for the survey design; adjusted odds ratio (aOR) estimated from multivariable logistic regression models that included sex, age, occupation, asset score (generated by adding number of assets that household owns), tribe, smoking within the household, cooking with charcoal, footwear and prior treatment of worms.
‡
P-values are from the Wald test adjusted for the survey design.