Question

What is vaccination? Mention the four ways in which vaccines are prepared, giving the name of one disease for which each type of vaccine is used.

Answer 1

Vaccination is the practice of artificially introducing germs or germ substances into the body for developing resistance to particular diseases.
The four ways in which vaccine are prepared are-
1. Killed germs are used for preparing vaccines. Eg. TAB vaccine for typhoid.
2. Living weakened germs are treated in a way that they become weak and cannot cause disease. They are then used for preparing vaccines. Eg. BCG vaccine for Tuberculosis.
3. Living fully virulent germs used for preparing vaccines. Eg. Smallpox or Cowpox virus.
4. Toxoids are toxins extracted from bacteria used for preparing vaccines. Eg. Diptheria.