Table 4.
Posterior mean coefficients, odds ratios (ORs), and 95% credible intervals (CrI) of spatial and non-spatial conditional autoregressive models of market days positive for highly pathogenic avian influenza H5N1 virus (Vietnam, 2011–2015).
| Coefficient, posterior mean (95% CrI) |
OR, posterior mean (95% CrI) |
|||
|---|---|---|---|---|
| Multivariable model (no spatially varying random effect) | Multivariable model (province as spatially varying random effect) | Multivariable model (no spatially varying random effect) | Multivariable model (province as spatially varying random effect) | |
| Suitability for rice growing | ||||
| High/moderate | Baseline | Baseline | Baseline | Baseline |
| Marginal/unsuitable | 0.47 (0.15, 0.78) | −0.04 (−0.51, 0.42) | 1.60 (1.17, 2.19) | 0.96 (0.60, 1.52) |
| Sampling month | ||||
| January | Baseline | Baseline | Baseline | Baseline |
| February | −0.27 (−0.67, 0.12) | −0.36 (−0.77, 0.05) | 0.76 (0.51, 1.13) | 0.70 (0.46, 1.05) |
| March | −0.87 (−1.40, −0.36) | −1.00 (−1.55, −0.47) | 0.42 (0.25, 0.70) | 0.37 (0.21, 0.63) |
| April | −1.01 (−1.55, −0.49) | −1.11 (−1.68, −0.57) | 0.37 (0.21, 0.62) | 0.33 (0.19, 0.57) |
| May | −1.48 (−2.19, −0.82) | −1.75 (−2.49, −1.06) | 0.23 (0.11, 0.44) | 0.17 (0.08, 0.35) |
| June | −0.27 (−1.19, 0.60) | −0.59 (−1.51, 0.29) | 0.76 (0.30, 1.83) | 0.55 (0.22, 1.34) |
| July | −0.50 (−1.47, 0.43) | −0.82 (−1.79, 0.12) | 0.61 (0.23, 1.54) | 0.44 (0.17, 1.13) |
| August | −0.35 (−1.26, 0.53) | −0.65 (−1.58, 0.26) | 0.70 (0.20, 1.70) | 0.52 (0.21, 1.30) |
| September | −0.80 (−1.60, −0.05) | −1.10 (−1.92, −0.33) | 0.45 (0.20, 0.95) | 0.33 (0.15, 0.72) |
| October | −1.80 (−3.44, −0.49) | −1.96 (−3.62, −0.62) | 0.16 (0.03, 0.61) | 0.14 (0.03, 0.54) |
| November | −0.53 (−0.99, −0.08) | −0.66 (−1.13, −0.20) | 0.59 (0.37, 0.92) | 0.52 (0.32, 0.82) |
| December | −0.80 (−1.20, −0.40) | −0.92 (−1.34, −0.51) | 0.45 (0.30, 0.67) | 0.40 (0.26, 0.60) |
| Average maximum temperature (°C) | ||||
| ≤24.47 | Baseline | Baseline | Baseline | Baseline |
| 24.48–28.74 | 0.72 (0.26, 1.20) | 0.15 (−0.75, 1.03) | 2.06 (1.29, 3.34) | 1.17 (0.47, 2.81) |
| 28.75–30.32 | 1.71 (1.29, 2.15) | 1.12 (0.21, 1.99) | 5.54 (3.63, 8.62) | 3.07 (1.23, 7.32) |
| ≥30.33 | 1.69 (1.23, 2.16) | 1.21 (0.26, 2.12) | 5.41 (3.43, 8.71) | 3.36 (1.29, 8.36) |
| River density (km length/km2) | 0.08 (−0.05, 0.21) | −0.05 (−0.29, 0.19) | 1.08 (0.95, 1.23) | 0.95 (0.75, 1.21) |
| Travel time (min) to nearest city with population ≥50,000 | −0.18 (−0.33, −0.04) | −0.07 (−0.24, 0.08) | 0.84 (0.72, 0.96) | 0.93 (0.78, 1.09) |
| Chicken density (heads/km2) | ||||
| <285 | Baseline | Baseline | Baseline | Baseline |
| 285–791.3 | 0.19 (−0.13, 0.51) | 0.03 (−0.39, 0.45) | 1.21 (0.88, 1.66) | 1.03 (0.68, 1.57) |
| 791.4–1,686.1 | 0.07 (−0.27, 0.41) | 0.00 (−0.41, 0.42) | 1.07 (0.77, 1.50) | 1.00 (0.66, 1.52) |
| ≥1,686.2 | −0.44 (−0.86, −0.03) | −0.37 (−0.87, 0.12) | 0.64 (0.42, 0.97) | 0.69 (0.42, 1.13) |
| Round | ||||
| Round 1 | Baseline | Baseline | Baseline | Baseline |
| Round 2 | 1.11 (0.76, 1.46) | 1.14 (0.76, 1.52) | 3.02 (2.13, 4.31) | 3.13 (2.14, 4.57) |
| Round 3 | 0.85 (0.48, 1.21) | 0.85 (0.47, 1.24) | 2.33 (1.62, 3.35) | 2.35 (1.60, 3.56) |
| Round 4 | −0.12 (−0.85, 0.61) | 0.06 (−0.68, 0.81) | 0.89 (0.43, 1.85) | 1.06 (0.51, 2.25) |
| Round 5 | 0.68 (−0.02, 1.33) | 0.76 (0.03, 1.44) | 1.97 (0.98, 3.78) | 2.14 (1.03, 4.23) |
| Round 6 | 1.25 (0.18, 2.29) | 1.57 (0.47, 2.65) | 3.48 (1.19, 9.91) | 4.81 (1.60, 14.16) |
| Model deviance information criterion | 1,934.81 | 1,822.10 | ||
Province included as a spatially varying random effect.