Skip to main content

Advertisement

Table 4 Bivariate logistic regression results for presence of An. arabiensis larvae: water body characteristics

From: Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

  Dongola Merowe
Habitats sampled OR* 95% CI P value† Habitats sampled OR 95% CI P value†
Water temperature (°C)     0.26     0.87
<24 366 1.00    533 1.00   
24–27.9 281 1.01 0.63–1.63 0.95 400 1.10 0.68–1.79 0.70
28–31.9 376 0.76 0.47–1.20 0.24 569 1.11 0.71–1.74 0.63
32+ 258 1.23 0.77–1.96 0.38 565 1.23 0.79–1.90 0.35
Salinity (%)     <0.0001     <0.0001
0 318 1.00    890 1.00   
0.01–0.25 689 5.02 2.66–9.48 <0.0001 807 2.88 1.95–4.26 <0.0001
>0.25 274 4.49 2.25–8.98 <0.0001 370 2.49 1.56–3.99 <0.0001
pH     <0.0001     0.0005
< 6.5 253 1.00    424 1.00   
6.5 756 1.00 0.62–1.63 0.99 1,358 1.05 0.68–1.61 0.83
> 6.5 272 2.59 1.55–4.31 <0.0001 285 2.29 1.39–3.78 0.001
Water turbidity     0.54     0.0002
Non-turbid 871 1.00    1,141 1.00   
Turbid 410 0.89 0.62–1.29   926 0.53 0.38–0.75  
Water depth (cm)     0.20     <0.0001
<10 844 1.00    1,148 1.00   
10–50 325 0.94 0.64–1.39 0.76 418 1.39 0.97–1.99 0.07
>50 112 0.53 0.25–1.12 0.10 501 0.32 0.18–0.55 <0.0001
Surface area (m 2 )     0.0001     <0.0001
<1 552 1.00    947 1.00   
1–10 438 1.97 1.36–2.86 <0.0001 619 3.86 2.62–5.68 <0.0001
>10 291 0.79 0.48–1.32 0.37 501 1.81 1.14–2.87 0.01
Degree of shading (%)     0.0008     <0.0001
<25 888 1.00    1,290 1.00   
25–75 285 0.56 0.35–0.89 0.01 546 0.67 0.45–0.97 0.04
>75 108 0.29 0.12–0.73 0.01 231 0.12 0.04–0.38 <0.0001
Presence of algae     <0.0001     <0.0001
No 1,027 1.00    1,701 1.00   
Yes 254 3.62 2.54–5.17   366 5.81 4.18–8.07  
Presence of vegetation     <0.0001     <0.0001
No 598 1.00    1,042 1.00   
Yes 683 2.18 1.52–3.13   1,025 2.27 1.62–3.17  
  1. * Odds ratio
  2. † P values in bold are from likelihood ratio tests (overall significance of exposure variables); for variables with multiple exposure levels P values from Wald tests are also reported.