Table 5 Univariate and multivariable analysis of risk factors associated with clinical malaria infections
Intervention shehias | Control shehias | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Survey population (n; %)1 | Malaria cases (n; %)2 | OR (CI95%) | aOR3(CI95%) | p value | Survey population (n; %)1 | Malaria cases (n; %)2 | OR (CI95%) | aOR3 (CI95%) | p value | |
Residing in households sprayed in the last 12 months | ||||||||||
No | 1316; 12.5 | 18; 23.4 | 1 (Ref) | 1 (Ref) | – | 1437; 12.3 | 24; 18.1 | 1 (Ref) | 1 (Ref) | – |
Yes | 9218; 87.5 | 59; 76.6 | 0.4; 0.3–0.7 | 0.5; 0.2–0.9 | 0.018 | 10,205; 87.7 | 109; 82.0 | 0.6; 0.4–0.9 | 0.6; 0.4–1.0 | 0.074 |
Residing in household with at least one mosquito net | ||||||||||
No | 1283; 12.2 | 9; 11.7 | 1 (Ref) | 1 (Ref) | – | 1739; 14.9 | 16; 12.0 | 1 (Ref) | 1 (Ref) | – |
Yes | 9251; 87.8 | 68; 88.3 | 1.0; 0.5–2.0 | 2.8; 0.9–9.1 | 0.085 | 9903; 85.1 | 117; 88.0 | 1.3; 0.8–2.2 | 2.6; 1.2–5.5 | 0.015 |
Residing in households with at least one mosquito net and/or sprayed in the past 12 months | ||||||||||
No | 293; 2.8 | 6; 7.8 | 1 (Ref) | 1 (Ref) | – | 200; 1.7 | 3; 2.3 | 1 (Ref) | 1 (Ref) | – |
Yes | 10,241; 97.2 | 71; 92.2 | 0.3; 0.1–0.7 | 0.4; 0.1–1.9 | 0.262 | 11,442; 98.3 | 130; 97.7 | 0.7; 0.2–2.0 | 0.5; 0.1–2.1 | 0.356 |
Age | ||||||||||
< 5 years | 1622; 15.4 | 4; 5.2 | 1 (Ref) | 1 (Ref) | – | 1785; 15.3 | 10; 7.5 | 1 (Ref) | 1 (Ref) | – |
5–14 years | 2725; 25.9 | 22; 28.6 | 3.3; 1.1–9.4 | 3.7; 1.2–11.1 | 0.019 | 3104; 26.7 | 30; 22.6 | 1.7; 0.8–3.6 | 2.1; 1.0–4.4 | 0.064 |
15–24 years | 1895; 18.0 | 27; 35.1 | 5.7; 2.0–16.4 | 4.4; 1.5–13.1 | 0.009 | 2034; 17.5 | 42; 31.6 | 3.8; 1.8–7.7 | 3.7; 1.7–8.0 | 0.001 |
> 25 years | 4292; 40.7 | 24; 31.2 | 2.2; 0.8–6.4 | 1.4; 0.5–4.3 | 0.510 | 4719; 40.5 | 51; 38.4 | 1.9; 1.0–3.8 | 1.6; 0.8–3.2 | 0.228 |
Sex | ||||||||||
Female | 5440; 51.6 | 26; 33.8 | 1 (Ref) | 1 (Ref) | – | 6028; 51.8 | 50; 37.6 | 1 (Ref) | 1 (Ref) | – |
Male | 5094; 48.4 | 51; 66.2 | 2.1; 1.3–3.4 | 2.0; 1.2–3.2 | 0.009 | 5614; 48.2 | 83; 62.4 | 1.8; 1.3–2.6 | 1.7; 1.1–2.5 | 0.009 |
Travel in last month | ||||||||||
No travel | 10,152; 96.4 | 54; 70.1 | 1 (Ref) | 1 (Ref) | – | 11,262; 96.7 | 95; 71.4 | 1 (Ref) | 1 (Ref) | – |
Within Zanzibar | 336; 3.2 | 3; 3.9 | 1.7; 0.5–5.3 | 2.3; 0.7–7.6 | 0.160 | 325; 2.8 | 3; 2.3 | 1.1; 0.3–3.4 | 1.1; 0.3–3.7 | 0.838 |
Outside of Zanzibar | 43; 0.4 | 20; 26.0 | 87.5; 46.4–165.1 | 103.4; 49.8–214.9 | < 0.001 | 55; 0.5 | 35; 26.3 | 75.8; 42.3–136.0 | 85.0; 4.2–159.8 | < 0.001 |
Reported use of a mosquito net the previous night | ||||||||||
No | 2606; 24.7 | 29; 37.7 | 1 (Ref) | 1 (Ref) | – | 3430; 29.5 | 45; 33.8 | 1 (Ref) | 1 (Ref) | – |
Yes | 7928; 75.3 | 48; 62.3 | 0.5; 0.3–0.8 | 0.5; 0.3–1.0 | 0.033 | 8212; 70.5 | 88; 66.2 | 0.8; 0.6–1.2 | 0.7; 0.5–1.1 | 0.167 |