Table 1. HA gene list.

Virus	HA subtype (Genbank or GISAID ID)
A/Mexico/4108/2009	H1 (pdm09) (GQ223112)
A/Puerto Rico/8/1934	H1 (CY009444)
A/Beijing/262/95	H1 (AY289928)
A/New Caledonia/20/1999	H1 (AY289929)
A/Brisbane/59/2007	H1 (CY058487)
A/Japan/305/1957	H2 (DQ508841)
A/swine/Missouri/4296424/2006	H2 (EU258943)
A/Philippines/2/82	H3 (CY121245)
A/Vietnam/1203/2004	H5 (EF541403)
A/Indonesia/5/05	H5 (EF541394)
A/duck/Guangxi/1378/2004	H5 (DQ320884)
A/duck/Hubei/wg/2002	H5 (DQ997094)
A/chicken/Vietnam/NCVD-016/2008	H5 (FJ842476)
A/Shanghai/02/2013	H7 (EPI439502)
A/Hong Kong/1073/99	H9 (AJ404626)
A/chicken/Hong Kong/G9/97	H9 (AF156373)

Abbreviation: GISIAD, Global Initiative on Sharing All Influenza Data