Assertion: smallpox | /r/CapableOf | infect human
Facets:
value: naturally
type: MANNER
Source sentences:
text: Smallpox only naturally infects humans and does not exist in a carrier state.
text: There is one major difference between the two viruses: vaccinia can infect several types of living beings, while variola infects only humans naturally and cynomolgus monkeys under highly artificial laboratory conditions.
text: Smallpox was a good candidate for eradication, for several reasons: It could only infect humans, so there could be no animal reservoir of the disease.
text: Smallpox infects only humans, and the last natural case of smallpox in the world occurred in 1977.