Fig. 3.

Effects of SARS-CoV-2 infection on activity, posture, and body condition scores in mice. C57BL/6 J (WT) and K18-hACE2 (TG) mice were infected with 0, 1 × 10³, 1 × 10⁴, or 1 × 10⁵ PFU of SARS-CoV-2 and several common, validated veterinary health measures were scored at baseline and daily until humane euthanasia occurred or 12–14 days post infection (n = 4–6/genotype/viral load). A) Average activity score (range 0–3, normal = 0). B) Average posture score (range 0–3, normal = 0). C) Average body condition score (range 1–5, normal = 3). Data are presented as the mean ± standard deviation. Dashed lines represent WT mice and solid lines represent TG mice. Different colored lines represent the different viral infection doses gray = 0 PFU, red = 1 × 10³ PFU, green = 1 × 10⁴ PFU, blue = 1 × 10⁵ PFU). Note, activity and posture scores increase from 0 when mice exhibit declines in health, whereas BCS drops below 3 when mice are underconditioned or rises above 3 when mice are overconditioned. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)