Immunisation is a method of artificially stimulating the immune system to provide protection against specific serious infections. This is done by giving a vaccine. A vaccine may be any one of the following:
- A live, but specially weakened (attenuated), organism such as oral polio vaccine.
- A dead organism such as intramuscular polio vaccine.
- An inactivated substance (a toxoid) produced by an organism such as diphtheria vaccine.
- Part of an organism such as hepatitis B vaccine.
Immunisation is a method of preventing some serious infectious diseases.
It is best not to use the word ‘vaccination’ as it means to immunise with vaccinia (cowpox) to protect against smallpox. However, the word vaccine is still used. Therefore, a vaccine is used to immunise an infant.