Define vaccine

Asked by bookragstutor 13 years ago 9/10/2012 1:36 AM

Last updated by Jill W 4 years ago 1/17/2021 12:45 PM

Answered by Jill W 4 years ago 1/17/2021 12:45 PM

A vaccine is a harmless variant or derivative of a pathogen that stimulates a host's immune system to mount defenses against the pathogen.