Inactivated Vaccines

•Active pathogens are grown in large numbers and then killed either by a chemical or heat. Although the pathogen is killed, or made to lose its reproduction capacity, various parts of the pathogen are intact. E.g The antigen (the chemical structure) that is recognised by the immune system is left unimpaired.
•When this dead microbe is introduced in the body, the immune system is tricked to respond by producing antibodies against specific antigens still left intact, without knowing that the pathogen is defective.
•As the pathogen is dead, it cannot reproduce nor cause even a mild disease. Thus, it is safe to administer to even people with lesser immunity, like the old and those who have comorbidity.
•Inactivated polio vaccine and the rabies vaccine are made this way.