Definition that contains smallpox virus
- myxoma virus a poxvirus closely related to smallpox virus; causes benign gelatinous tumors in humans
- variola minor virus a type of smallpox virus that has a fatality rate of about 1 percent
- variola major a type of smallpox virus that has a fatality rate of up to 25 percent
- variola major virus a type of smallpox virus that has a fatality rate of up to 25 percent
- variola minor a type of smallpox virus that has a fatality rate of about 1 percent