The immunologic defenses of the body respond to microbial invasion by producing protective antibodies or cell-mediated immunity, or both. Appropriate administration of specific microbial antigens, as in a vaccine, can provoke effective, longterm resistance to infection. Conserved microbial molecules can also stimulate the development of innate immune responses. This too enhances resistance to infection and may be clinically useful.

Last full review/revision March 2012 by Ian Tizard, BVMS, PhD, DACVM