Table 3. Different amino acid residues in the HA of the H5N1 viruses isolated from wild birds, humans and tigers.

Virusa	Amino acid residue sites (H3 numbering)
	77	193	225	246	260	397	475	509+	531
A/Alberta/01/2014	D	K	R	E	V	R	N	I	M
A/tiger/Jiangsu/01/2013	D	R	G	E	V	R	N	I	I
Ws/HN/SMX1/2015	S	K	G	E	I	K	N	V	M
Ws/HN/SMX3/2015	S	K	G	E	I	K	D	V	M
Ws/HN/SMX4/2015	S	K	G	E	I	K	N	V	M
Ws/HN/SMX9/2015	S	K	G	E	I	K	D	V	M
Po/HN/SMX1/2015	S	K	G	K	I	K	N	V	M
En/HN/SMX1/2015	S	K	G	E	I	K	D	V	M

509+: there is a gap after the 509^th residue in H3 protein compared with these H5 proteins.

^aWs: whooper swan; Po: pochard; En: environment; HN: Henan.