Vaccination

A small amount of weakened or dead viruses or bacteria or proteins made in labs that imitate some virus or bacteria when given to humans in safe and effective quantities for the prevention or cure of the disease is known as vaccination and immunization. This weakened form of disease when injected to humans will trigger the immune system that either produces antibodies for that particular disease or induces processes that enhance immunity. Because of the above process, if the person is exposed to the same kind of disease, then the immune system is prepared to fight off the infection. Vaccination prevents the onset of diseases or reduces the severity of the disease.

The main goal of public health is to prevent disease. It is easier and more cost-effective to prevent disease than to treat it. Hence, immunization protects the person from the diseases as well as stops the spread to others. Immunization has eradicated the common epidemic diseases such as measles, mumps, whooping cough, etc and near eradication of polio and smallpox.

Few vaccines are given only once whereas few need boosters for maintaining successful immunization and protection against the disease.