Symptom severity scoring system.

Symptom severity scoring system was adapted from Murphy et al.11. Animals were scored twice post-infection. Cumulative score may range from 0 to 10, indicating no to severe illness.

本研究采用的症状严重程度评分系统改编自Murphy等人的研究（文献11）。受试动物于感染后接受两次评分，其累积评分区间为0至10，分别对应无病症至重症的不同状态。