Following i.n. infection, the OMVdA-ALS-F1V immunization afforded 80% protection (Fig. 4D), while the OMVdA-LATM5-F1V and rF1V immunizations provided 20% protection, and neither the OMVdA-NA immunization nor PBS offer any protection against the same i.n. challenge (Fig. 4D). This evidence concerns the gene XK and infection.