Table 1.

Virus strains, isolates and infectious cDNA clone used in the study.

Virus	Strain/isolate	Relevant data
WNV	NY99	North American strain isolated in New York in 1999 (Lanciotti et al., 1999; Martin-Acebes and Saiz, 2011)
	B13	Persistent variant of NY99 isolated from a mice 56 days after vertical infection (Blazquez and Saiz, 2010)
	ArD27875	Isolated in Senegal in 1990 (Beasley et al., 2002)
	Egypt101	Isolated in Egypt in 1950 (Beasley et al., 2002)
	B956	Isolated in Uganda in 1937 (Smithburn et al., 1940)
	pFLWNV (WT)	Infectious cDNA clone containing a derivative of the North American strain 3356 isolated in New York in 2000 (Shi et al., 2002)
USUV	SAAR 1776	South African reference strain (Bakonyi et al., 2004)