Table 2. PRRSV strains used in this study.

No.	Isolate	Identity (%)a)	Province	Year	Access no.	No.	Isolate	Identity (%)a)	Province	Year	Access no.
1	S1	89.1	Henan	1998	DQ459471	21	09HEN2	97.7	Henan	2009	JF268680
2	HN1	88.8	Henan	2002	AY457635	22	09HUN1	97.6	Hunan	2009	JF268673
3	HuN	98.4	Hunan	2006	EF517962	23	09HUN2	98.0	Hunan	2009	JF268674
4	HN-HW	98.7	Hunan	2006	FJ797690	24	WUH4	99.0	Hubei	2011	JQ326271
5	HUN4	98.9	Hunan	2006	EF635006	25	HZ-31	95.2	Hubei	2012	KC445138
6	HUB1	98.6	Hubei	2006	EF075945	26	HeNan-A1	98.5	Henan	2013	KJ002451
7	HUB2	98.7	Hubei	2006	EF112446	27	HeNan-A2	96.6	Henan	2013	KJ002452
8	WUH1	98.1	Hubei	2006	EU187484	28	Henan-A3	96.9	Henan	2013	KJ019330
9	WUH2	97.7	Hubei	2006	EU678352	29	Henan-A4	97.0	Henan	2013	KJ534539
10	Henan-1	98.6	Henan	2007	EU200962	30	Henan-A5	97.0	Henan	2013	KJ534540
11	07HEN	98.6	Henan	2007	FJ393457	31	Henan-A6	97.2	Henan	2013	KJ534541
12	HN2007	98.5	Henan	2007	EU880437	32	Henan-A7	97.5	Henan	2013	KJ534542
13	Em2007	93.1	Hubei	2007	EU262603	33	Henan-A8	97.5	Henan	2013	KJ534543
14	08HuN	98.6	Hunan	2008	GU169411	34	Henan-A9	96.2	Henan	2013	KJ546412
15	WUH3	98.6	Hubei	2008	HM853673	35	Henan-A10	97.2	Henan	2013	KJ609516
16	09HUB1	97.9	Hubei	2009	JF268682	36	Henan-A11	96.2	Henan	2013	KJ609517
17	09HUB2	97.9	Hubei	2009	JF268683	37	Henan-A12	97.2	Henan	2014	KJ819934
18	09HUB5	97.9	Hubei	2009	GU168568	38	Henan-A13	97.0	Henan	2014	KJ819935
19	09HUB7	97.6	Hubei	2009	GU168567	39	Henan-A14	96.7	Henan	2014	KJ819936
20	09HEN1	97.7	Henan	2009	JF268684	40	HUN-2014	100	Hunan	2014	KP330232

a) Identity with PRRSV HUN-2014 strain.