Table 1. Variables used in the analysis of highly pathogenic avian influenza distribution in Thailand (subdistrict level) and Suphanburi Province (village level).

Category	Description	Abbreviation
Poultry*	No. broilers and layer hens	BrLaCh
	No. native chickens	NaCh
	No. meat and layer ducks	MeLaDu
	No. free-grazing ducks	FgDu
	No. cocks	Co
	No. other poultry	Ot
Land use/water†	Proportion of land occupied by wetland in the subdistrict, and in a 1-, 2-, 5-, and 10-km radius neighborhood	Pwet, Pwet1K, Pwet2K, Pwet5K, Pwet10K
	Proportion of land occupied by rice fields in the subdistrict, and in a 1-, 2-, 5-, and 10- km radius neighborhood	Price, Price1K, Price2K, Price5K, Price10K
	River/stream density (per km2) in the subdistrict and in a 1-, 2-, 5-, and 10-km radius neighborhood	Sd, Sd1K, Sd2K, Sd5K, Sd10K
People/roads‡	No. humans	Hpop
	No. roads	Nroads
Topographic§	Elevation, m	Alt
	Slope, degrees	Slp

*Census in the subdistrict or village.
†Estimate in the subdistrict was not used for the village-level analysis; distance-based variables between the 1- and 10-km neighborhood were estimated around the village point or subdistrict centroid.
‡No. roads in the subdistrict or connected to the village.
§These variables were averaged in the subdistrict polygon for subdistrict level analysis or extracted at the point of the village for village-level analysis.