Table 3.
Overview of spatial variables among three subtypes of highly pathogenic avian influenza virus infected premises (H5N1, H5N8, and H56) in South Korea.
| Subtype | ||||
|---|---|---|---|---|
| Variables (unit) | H5N1 (n = 88) |
H5N8 (n = 339) |
H5N6 (n = 335) |
p-value |
| Farm species | ||||
| Chicken (no. of farms) | 34 | 56 | 197 | - |
| Domestic duck (no. of farms) | 54 | 283 | 138 | - |
| Topology | ||||
| Elevation (m) | 54.08 (42.03) | 50.15 (41.68) | 71.03 (49.14) | <0.01*‡ |
| Topological wetness index† | 10.45 (1.37) | 11.07 (1.83) | 10.63 (1.59) | <0.01*‡ |
| Land-use/cover | ||||
| Proportion of forest within a 3 km radius (%) | 25.67 (20.29) | 21.08 (17.21) | 29.45 (19.47) | <0.01*‡ |
| Proportion of rice field within a 3 km radius (%) | 33.58 (14.81) | 37.33 (11.29) | 32.09 (13.15) | <0.01*‡ |
| Proportion of waterbody within a 3 km radius (%) | 2.98 (2.73) | 2.44 (1.63) | 2.77 (1.80) | <0.01*‡ |
| Proportion of wetland within a 3 km radius (%) | 1.13 (1.09) | 0.97 (0.89) | 1.22 (1.89) | 0.07‡ |
| Minimum distance to driveway (km) | 0.53 (0.47) | 0.59 (0.51) | 0.43 (0.41) | <0.01*‡ |
| Poultry and human | ||||
| Human (no. of inhabitant/10 km2) | 30.40 (42.02) | 17.69 (19.61) | 31.768 (39.74) | <0.01*§ |
| Chicken farm (no. of farms/km2) | 0.34 (0.27) | 0.60 (1.20) | 0.62 (0.76) | <0.01*§ |
| Domestic duck farm (no. of farms/km2) | 0.32 (0.37) | 0.89 (1.13) | 0.51 (0.97) | <0.01*§ |
| Wildlife and live bird market | ||||
| Minimum distance to major wintering site for wild bird (km) | 5.55 (5.77) | 6.32 (5.56) | 6.59 (4.45) | 0.23‡ |
| Minimum distance to live bird market (100 m) | 1.04 (0.10) | 3.10 (12.8) | 2.41 (9.24) | <0.04*§ |
Values are expressed as mean (standard deviation).
†
Topological wetness index indicates the level of water accumulation and local drainage.
‡
Using ANOVA test.
§
Using Kruskal–Wallis test.