Furthermore, we tested a range of independent mouse strains and found that BALB/c mice followed the disease course of resistant B6 mice and had comparably low IFN levels (Supplementary Fig. 3a,b), whereas CBA/J and DBA/2 mice exhibited high susceptibility to influenza, resembling the 129 strains, and also displayed sustained, high IFNα, -β and -λ levels throughout infection (Supplementary Fig. 3c–f). The gene discussed is IFNA1; the disease is infection.