註釋 Variola virus (VARV) is the causative agent of smallpox and has been globally eradicated with no naturally occurring infections reported since 1977. Because Variola virus (VARV) has been eradicated from the environment, alternative animal models are used to evaluate potential treatments for smallpox. One model of smallpox utilizes intranasal (IN) inoculation of BALB/c mice with ECTV, causative agent of mousepox disease in mice, due to the genetic and disease presentation similarities between ECTV and VARV. The ECTV-mouse model reproduces many features similar to that of human smallpox including severe, acute systemic disease caused by a low virus infectious dose; lack of pulmonary involvement early in the disease progression; and a presentation of a characteristic pustular rash in mice that survive the acute phase of disease. Thus, the BALB/c mouse model was developed to characterize and study ECTV infection and pathogenesis. First, the propagation of ECTV resulted in a certified working stock of virus and the LD90 and LD50 were determined to be 32.10 PFU and 