Write a short note on vaccination.

Hint: A vaccine is a substance that involves protecting the human body from certain diseases. In the vaccines, a dead or weakened version of a microbe is present. Generally, the vaccine helps the immune system to recognize and destroy the living microbe during a future infection.

Complete answer:
Vaccination is the process of developing the immune system to build protection from disease. In the vaccination, the vaccine is injected into the human body. A vaccine is a product that improves the immunity of the human body to a certain disease. It is produced biologically.
The vaccine contains typical agents of a microorganism that causes diseases and is produced from weakened or dead forms microbes while one surface of microbes is proteins or toxins. The vaccine stimulates the immune system of the body and identifies the attack microbes as the foreign agent to destroy it. Due to vaccines, the immune system is able to recognize and destroy any microorganisms encountered later.
The process of vaccination developed the body's adaptive immunity which prevents sickness from an infectious disease. When the vaccination takes place in a large percentage of a population it leads to herd immunity results. The ability and working mechanism of vaccination has been researched and verified scientifically. A mass vaccination process results in widespread immunity that helps in the successful eradication of smallpox and the elimination of diseases such as polio and tetanus worldwide.
Generally, there are four types of vaccines that are used. At first, live virus vaccines contain the weakened form of the virus. The measles, mumps, and rubella, and chickenpox vaccine are its examples.
Next is the killed or inactivated vaccines that are made from a protein or other small pieces taken from a virus or bacteria. The whooping cough vaccine is an example of this type of vaccine.
The third is the toxoid vaccines. It contains a toxin or chemical produced by bacteria or viruses and its examples are diphtheria and tetanus vaccines. The fourth one is biosynthetic vaccines made from man made substances that are very similar to pieces of the virus or bacteria. The Hepatitis B vaccine is an example of this vaccine.

Note: Vaccination is a scientific system of developing human immunity without infection. The weakened or killed pathogens are injected into the body through the vaccination that builds immunity against the particular pathogen. This pathogen produced antibodies in the body. Thus, a vaccinated person becomes able to fight against the pathogen. Generally, vaccination is used for T.B., mumps, polio, smallpox, typhoid, and other infectious diseases.