Vaccination and immunization

Vaccination is the process of administering a vaccine into the body — the deliberate act of introducing the preparation to trigger protection against a specific disease. Immunization describes the actual biological outcome: the process by which the body builds up immunity to that disease as a result of the vaccine. In other words, vaccination is the intervention, and immunization is the physiological change it produces. A vaccine works by giving the immune system a controlled first encounter with the pathogen (or a harmless stand-in for it), which the system fights off and then 'records' in its memory cells; the next time the real pathogen enters the body, the memory response allows it to be eliminated far more quickly than it otherwise would be. Once the body has demonstrated it ca …