Four animals of each strain were scheduled to be sacrificed at 1 and 3 days post infection (p.i.), and 8 hamsters were scheduled to be sacrificed at 7 days p.i. However, 6 of the 8 Day 7 STAT2 KO hamsters were moribund at around 4 days p.i. (Fig 1A). Here, STAT2 is linked to infection.