Antibody production is regarded as sufficient to prove the vaccine's effectiveness, and it is rare for subjects to be exposed directly to the biological agent (usually a virus or bacteria) the vaccine is supposed to provide immunity against.
Antibody production is regarded as sufficient to prove the vaccine's effectiveness, and critics point out that a relationship between antibody production and immunity is an assumption that has never been proved. It is rare for subjects to be exposed directly to the biological agent (usually a virus or bacteria) the vaccine is supposed to provide immunity against.