Table 7.
Factors related to anopheline larval density.
| Habitat characteristics | Number of obs. | Number of dips | Total number of anopheline larvae | Anopheline larval density (per dip) |
RR | 95%CI | p-value |
| Zone | 0.028 | ||||||
| Hann Maristes | 18 | 209 | 208 | 1.00 | ref. | ||
| Pikine | 27 | 140 | 357 | 2.55 | 1.66 | 0.77 – 3.60 | 0.198 |
| Université | 14 | 54 | 246 | 4.56 | 2.23 | 0.91 – 5.46 | 0.080 |
| Yarakh | 2 | 18 | 110 | 6.11 | 2.28 | 0.41 – 12.76 | 0.348 |
| Ouest Foire | 22 | 93 | 578 | 6.22 | 3.09 | 1.38 – 6.95 | 0.006 |
| Almadies | 38 | 179 | 1309 | 7.31 | 4.09 | 1.98 – 8.45 | <0.001 |
| Gibraltar | 2 | 9 | 160 | 17.78 | 8.10 | 1.48 – 44.39 | 0.016 |
| Parcelles Grand Medine * | 0 | - | - | - | |||
| Liberté 5 | 0 | - | - | - | |||
| Yoff Village | 0 | - | - | - | |||
| Habitat type | <0.001 | ||||||
| "Céanes", cemented weels or basins | 8 | 53 | 126 | 2.38 | ref. | ||
| Waterproof containers | 5 | 17 | 30 | 1.76 | 2.56 | 0.45 – 14.72 | 0.291 |
| Swamp areas, marshes, ponds or lakes | 22 | 116 | 467 | 4.03 | 14.76 | 3.76 – 57.88 | <0.001 |
| Ditches or puddles | 80 | 488 | 2137 | 4.38 | 15.96 | 4.44 – 57.36 | <0.001 |
| Man-made water collections | 4 | 16 | 82 | 5.13 | 17.45 | 2.62 – 116.14 | 0.003 |
| Canals | 4 | 12 | 126 | 10.50 | 22.50 | 3.90 – 129.71 | <0.001 |
| Period | 0.762 | ||||||
| Weeks 1 – 4 | 57 | 328 | 1775 | 5.41 | ref. | ||
| Weeks 5 – 8 | 66 | 374 | 1193 | 3.19 | 0.94 | 0.63 – 1.40 | |
| Temporary collection | 0.292 | ||||||
| No | 23 | 134 | 379 | 2.83 | ref. | ||
| Yes | 100 | 568 | 2589 | 4.56 | 1.44 | 0.73 – 2.85 | |
| Perimeter (metres) | 0.755 | ||||||
| <20 m | 49 | 226 | 1078 | 4.77 | ref. | ||
| >= 20 m | 74 | 476 | 1890 | 3.97 | 0.93 | 0.59 – 1.46 | |
| Water temperature (n = 93) | <0.001 | ||||||
| <30°C | 33 | 228 | 475 | 2.08 | ref. | ||
| >= 30°C | 60 | 307 | 1611 | 5.25 | 3.34 | 1.97 – 5.68 | |
| Turbidity (n = 88) | 0.592 | ||||||
| <13 (clear) | 28 | 142 | 700 | 4.93 | ref. | ||
| >= 13 (turbid) | 60 | 392 | 1261 | 3.22 | 0.87 | 0.52 – 1.46 | |
| Surface vegetation (%) | 0.001 | ||||||
| <20% | 89 | 504 | 2596 | 5.15 | ref. | ||
| >= 20% | 34 | 198 | 372 | 1.88 | 0.41 | 0.24 – 0.70 | |
| Sunlight (%, n = 120) | 0.674 | ||||||
| <80% | 72 | 447 | 1194 | 2.67 | ref. | ||
| >= 80% | 48 | 244 | 1665 | 6.82 | 1.13 | 0.64 – 2.00 | |
| Presence of predator(n = 104) | 0.865 | ||||||
| No | 48 | 308 | 1326 | 4.31 | ref. | ||
| Yes | 56 | 286 | 1245 | 4.35 | 0.96 | 0.59 – 1.56 | |
| Presence of Culicinae larvae (n = 106) | 0.016 | ||||||
| No | 51 | 291 | 1259 | 4.33 | ref. | ||
| Yes | 55 | 321 | 1033 | 3.22 | 1.71 | 1.10 – 2.64 | |
Adjusted (by study area) risk ratio (RR) estimated by GEE negative binomial regression model. Bivariate analysis; 123 observations of anopheline breeding sites, unless otherwise indicated.
* Water collections found outside of the 200 × 200 m study area