Question

how are vaccins usful to us? ​

Answer 1

Explanation:

Vaccines contain a microorganism or virus in a weakened, live or killed state, or proteins or toxins from the organism. In stimulating the body's adaptive immunity, they help prevent sickness from an infectious disease. When a sufficiently large percentage of a population has been vaccinated, herd immunity results.

Answer 2

Answer: vaccine produces immunity to a disease by stimulating the production of antibodies. Vaccines are suspensions of killed or weakened microorganisms. which kills the bacteria or viruses which entered the body.