Figure 3.

Clinical disease in C57BL/6 mice infected IC with different CHIKV strains. Four-to-six week old C57BL/6J mice were IC infected with 1000 PFU of SINV TE or CHIKV strains SL15649, AF15561, or SM2013 or mock infected with PBS and weighed (A) and clinically scored (B) daily; for (A), n = 46 mice per group for SL15649, AF15561, and SM2013, n = 31 mice per group for PBS Mock and SINV TE; data presented as mean ± SEM; dotted line represents initial starting weight; Mock versus SL15649: * p < 0.05, *** p < 0.001, **** p < 0.0001; Mock versus AF15561: # p < 0.05, ## p < 0.01, Dunnett’s multiple comparisons test; for (B), n = 20 mice per group; 0 = no clinical signs, 1 = mild abnormal gait and tail posture, 2 = hunched posture, abnormal gait, unkempt hair coat, 3 = marked hunched posture, ataxia, and decreased ambulation (humane endpoint), 4 = moribund/dead/euthanized.