Table 3.
Effects of climatic factors and interventions on the spatio-temporal patterns of malaria incidence estimated from Bayesian negative binomial models adjusted for interventions, socio-economic and health seeking behavior proxies.
| Predictor | Children <5 years |
Individuals 5 years and above |
|---|---|---|
| IRR (95%BCI) | IRR (95%BCI) | |
| Rainfall (mm) (≤77.0) | 1 | 1 |
| 77.1–126.0 | 1.09 (1.07, 1.13)a | 1.08 (1.05, 1.10)a |
| 126.1–354 | 1.13 (1.11, 1.17)a | 1.09 (1.06, 1.13)a |
| NDVI (≤0.55) | 1 | 1 |
| 0.56–0.66 | 1.13 (1.10, 1.16)a | 1.18 (1.14, 1.23)a |
| 0.67–0.81 | 1.19 (1.14, 1.24)a | 1.28 (1.21, 1.32)a |
| LSTD (°C) (≤26.5) | 1 | 1 |
| 26.6–29.3 | 1.06 (1.03, 1.09)a | 1.04 (1.01, 1.06)a |
| 29.4–44.6 | 0.94 (0.88, 0.98)a | 0.94 (0.92, 0.97)a |
| LSTN (°C) (≤17.1) | 1 | 1 |
| 17.2–18.9 | 1.00 (0.93, 1.11) | 1.00 (0.97, 1.04) |
| 19.0–23.3 | 1.00 (0.94, 1.10) | 1.00 (0.95, 1.05) |
| Altitude | 0.78 (0.72, 0.79)a | 0.90 (0.86, 0.94)a |
| Land cover (Others) | 1 | 1 |
| Crops | 1.07 (1.04, 1.10)a | 1.10 (1.05, 1.17)a |
| Distance to water bodies (km)(≤16.9) | 1 | 1 |
| 17.0–45.8 | 1.01 (0.93, 1.06) | 0.87 (0.83, 0.90)a |
| 46.0–152.6 | 0.86 (0.83, 0.90) | 0.89 (0.80, 0.91)a |
| Interventionsc | ||
| ITNs | 0.27 (0.21, 0.38)a | 1.19 (1.00, 1.20) |
| ACTs | 0.70 (0.62, 0.78)a | 0.54 (0.42, 0.63)a |
| Interactions | ||
| Rainfall(mm) (≤77.0) ∗ ITNs | 1 | 1 |
| (77.1–126.0) ∗ ITNs | 1.04 (0.67, 1.60) | 1.19 (0.78, 1.79) |
| (126.1–354) ∗ ITNs | 0.79 (0.50, 1.26) | 0.82 (0.52, 1.28) |
| NDVI (≤0.55) ∗ ITNs | 1 | 1 |
| (0.56–0.66) ∗ ITNs | 1.60 (1.03, 2.46)a | 1.84 (1.21, 2.80)a |
| (0.67–0.81) ∗ ITNs | 3.20 (1.88, 5.43)a | 3.08 (1.85, 5.13)a |
| LSTD (°C) (≤26.5) ∗ ITNs | 1 | 1 |
| (26.6-29.3) ∗ ITNs | 1.47 (1.05, 2.31)a | 1.82 (1.18, 2.82)a |
| (29.4–44.6) ∗ ITNs | 1.70 (1.03, 2.80)a | 2.46 (1.52, 3.97)a |
| Rainfall(mm) (≤77.0) ∗ ACTs | 1 | 1 |
| (77.1–126.0) ∗ ACTs | 1.00 (0.76, 1.30) | 1.10 (0.85, 1.42)a |
| (126.1–354) ∗ ACTs | 1.11 (0.82, 1.49) | 1.26 (0.95, 1.67)a |
| NDVI (≤0.55) ∗ ACTs | 1 | 1 |
| (0.56–0.66) ∗ ACTs | 1.12 (1.07, 1.48)a | 1.05 (1.01, 1.37)a |
| (0.67–0.81) ∗ ACTs | 1.26 (1.13, 1.72)a | 1.18 (1.06, 1.59)a |
| LSTD (°C) (≤26.5) ∗ ACTs | 1 | 1 |
| (26.6–29.3) ∗ ACTs | 1.18 (1.05, 1.55)a | 1.37 (1.06, 1.77)a |
| (29.4–44.6) ∗ ACTs | 0.91 (0.68, 0.97)a | 1.24 (0.92, 1.66) |
| Wealth index (Poorest) | 1 | 1 |
| Poorer | 0.82 (0.77, 0.88)a | 1.09 (0.99, 1.14) |
| Middle | 0.71 (0.67, 0.74)a | 0.86 (0.83, 0.90)a |
| Richer | 0.70 (0.68, 0.76)a | 0.83 (0.78, 0.87)a |
| Richest | 0.78 (0.73, 0.86)a | 0.91 (0.79, 0.95)a |
| Malaria treatment seeking behavior | 0.47 (0.40, 0.53)a | 0.54 (0.45, 0.60)a |
| Temporal trendb | Median (95%BCI) | Median (95%BCI) |
|---|---|---|
| 2014 | −0.02 (−0.03, −0.01) | −0.18 (−0.21, −0.16) |
| 2015 | −0.04 (−0.06, −0.04) | −0.39 (−0.42, −0.37) |
| 2016 | −0.03 (−0.05, −0.02) | −0.15 (−0.20, −0.10) |
| 2017 | −0.09 (−0.12, −0.07) | −0.33 (−0.40, −0.29) |
| Seasonal parameters | ||
| Amplitude | ||
| Annual | 0.11 (0.04, 0.17) | 0.31 (0.19, 0.36) |
| Semi-annual | 0.14 (0.07, 0.18) | 0.08 (0.03, 0.11) |
| Phase (months) | ||
| Annual | 2.57 (1.76, 5.90) | 2.40 (1.90, 5.63) |
| Semi-annual | 2.83 (1.19, 5.81) | 1.76 (0.73, 4.64) |
| Spatio-temporal parameters | ||
| Spatial variance | 1.42 (1.06, 1.81) | 1.27 (0.97, 1.66) |
| Temporal variance | 18.15 (12.21, 26.06) | 18.61 (12.44, 27.06) |
| Temporal correlation | 0.94 (0.90, 0.98) | 0.98 (0.95, 0.99) |
| Dispersion | 6.84 (6.61, 7.09) | 7.95 (7.68, 8.24) |
a
Statistically important effect.
b
Versus 2013.
c
Coverage was modeled on the scale of 0 to 1, therefore one unit increase in coverage corresponds to a 100% increase which implies a shift of the current by 100%.