The up-regulation of RSAD2 (radical S-adenosyl methionine domain containing 2), IFIT5 (interferon induced protein with tetratricopeptide repeats 5), OASL (2′-5′-oligoadenylate synthetase-like), ISG12(2) (interferon-stimulated genes) and Mx (myxovirus resistance) have been reported in the infection of infectious bursal disease virus (IBDV), which is another important pathogen similar to ARV but can cause much higher mortality and much more serious immunosuppression [43]. The gene discussed is MX1; the disease is infection.