VACCINES are preparations of pathogens introduced to the body to cause immune responses (Option a). These vaccines are based on death pathogens.
Vaccines are preparations that are inoculated into the body in order to produce a corresponding immune response.
In consequence, these preparations (vaccines) can be used for the treatment of different contagious and non-contagious diseases.
The categories or types of vaccines include vaccines based on the whole pathogen (e.g., virus), subunit (protein), viral vector (DNA viral vectors) and vaccines based on nucleic acids (either RNA and DNA).
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