Fig. 1: Study design and comparison of skin lesions in rhesus macaques from the MPXV and SIV-MPXV groups.

a Study design. Group A (MS, SIV-MPXV, n = 6) and Group B (MP, MPXV, n = 6). b SIV RNA and MPXV DNA loads in the plasma of monkeys before (n = 6) and after 10 dpi (n = 3). The shaded areas within the dashed lines indicate the standard deviation (SD). c,d Skin lesion counts (n = 6 before 10 dpi, n = 3 after 10 dpi) and duration from onset to resolution. Statistical differences between groups were analyzed using two-way ANOVA. ****P < 0.0001. The exact P values are both P < 0.0001 on 10 dpi and 14 dpi (c). The solid triangles indicate the time of skin lesion appearance and healing (d). e Images of skin lesions in monkeys from the MP and MS groups at 10 dpi. f Skin lesion counts at different regions in the MP and MS groups at 10 dpi (n = 6). Statistical differences between groups were analyzed using two-way ANOVA with Tukey’s correction for multiple comparisons. *P < 0.05, **P < 0.01. The exact P-values are: P = 0.0302 in the limbs and P = 0.0068 in the pygal. g MPXV DNA loads in skin lesions in the MP and MS groups (n = 3). Statistical differences were analyzed by a two-tailed unpaired t test. **P < 0.01 (P = 0.0022). h Histopathology of skin lesions in macaques after the MPXV challenge. The black arrows represent necrotic cell fragments and granulocytes, the gray arrows refer to fibrous cell necrosis, the purple arrows indicate inflammatory cell infiltration mainly composed of lymphocytes and granulocytes, the orange arrows point to an increase in the number of spinous cell layers, the blue arrows show loose arrangement of connective tissue, and the dark blue arrows show mild edema. Data are shown as the mean ± SD (b, c, f, g). The ‘n’ represents the number of independent biological replicates. Source data are provided as a Source Data file.