Question

Question 7.

To date, there is no vaccine against corona virus. Briefly, explain how vaccines work, and why some vaccines need a boost?

Answer 1

vaccine is a substance that contains  virus or bacterium in a form that is not harmful(either killed or attenuated), given to a person to prevent them from getting the disease that the virus or bacterium causes.

vaccine works by training the immune system to recognize and combats pathogens.For this certain molecules are introduced to the body (called "antigens") which stimulates the active immunity of our body and alert immune cells called lymphocytes which responds by producing antibodies.These antibodies remains in the body for long time so that whenever the body comes in contact with the same microorganism again these antibodies will act immediately and destroy them.

a booster dose is an administration of extra dose of vaccine after a prime dose(which is the previous dose).

Some diseases are more resilient than others. Over time the body can lose the antibodies first provided by a vaccination or memory cells of our body specific to that disease have loss their function , leaving body open to the disease once again.In such conditions booster dose is given where patient will be reexposured to the immunising antigen, and subsequent antibodies will be reproduced.

example. Adult should get seasonal flu vaccine (influenza vaccine) every year.

  Tdap is the booster for pertussis and should be administerd in every 10 year.