Assertion: vaccine's virus | /r/HasProperty | vaccinia
Facets:
Source sentences:
text: The first vaccine was introduced by British physician Edward Jenner , who in 1796 used the cowpox virus (vaccinia) to confer protection against smallpox , a related virus, in humans.
text: The vaccine is made from a virus called vaccinia, which is a poxvirus similar to smallpox, but less harmful.
text: Vaccines containing vaccinia viruses were used effectively in the campaign to eradicate smallpox.