Immunization is the strengthening of a persons defence mechanism against infection. An immunobiological substance called vaccine is injected into a person for protection against a specific disease.
Vacca means cow in Latin. The word vaccination came to be used after Edward Jenner, an English doctor, experimentally infected a boy with extract from cowpox lesion before infecting him with small
pox in his attempt to make the boy develop resistance to smallpox.
There has been a significant drop in the incidence of infectious diseases for which vaccination has been introduced. An example of this is smallpox, once a major cause of death worldwide. The smallpox virus is now found only in freezers in high-containment laboratories.
Vaccines are available for many infectious diseases. In 1974, World Health Organisation (WHO) launched an Expanded Programme of immunization (EPI) to protect the children of the world against diphtheria, whooping cough, tetanus, polio, TB and measles. The Universal immunization Programme was started in India in1985, along the guidelines of WHO.
How It All Began
How Vaccines Work
Types of Vaccines