Vaccine It is a biological preparation that provides immunity (or protection) against a particular disease.
A vaccine consists of dead or weakened microbes which when introduced in a healthy body, produces suitable antibodies to fight and kill the invading bacteria/microbes.
These antibodies remain in the body to protect from disease causing microbes, thus developing immunity. The diseases which can be prevented by vaccination are polio, cholera, tetanus, rabies, TB, smallpox, measles and hepatitis.