what is vaccine ? how does it works ?

Asked by tinu1972 | 26th Jul, 2015, 07:34: PM

Expert Answer:

A vaccine is a product that produces immunity from a disease and can be administered through needle injections or by mouth.
When foreign invaders such as bacteria or virus enter the body, immune cells called lymphocytes respond by producing antibodies.These antibodies fight the invader known as an antigen and protect against further infection.

Answered by Sivanand Patnaik | 27th Jul, 2015, 08:09: AM