Vaccines and Immunization

Vaccination is the administration of antigenic material (a vaccine) to stimulate an individual’s immune system to develop adaptive immunity to pathogen. Vaccine can prevent or ameliorate infectious disease. Vaccination is the most effective method of preventing infectious diseases; widespread immunity due to vaccination is largely responsible for the worldwide eradication of the smallpox and elimination of diseases such as polio, measles and tetanus from much of the world.

Immunization is the process by which individual’s immune system becomes fortified against an agent known as immunogen. When this system is exposed to molecules that are foreign to the body, called non-self it will orchestrate an immune response, and it will also develop the ability to quickly respond to a subsequent encounter because of immunological memory. This is a function of the adaptive immune system. Therefore by exposing an animal to an immunogen in a controlled way, its body can learn to protect itself this is called active immunization. Passive immunization is direct introduction to these elements into the body, instead of production of these elements by the body itself.