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How Do Vaccines Work? An Easy Explanation for Children

Team StoryWeavers|February 14, 2023, 17:58 IST|

Hello, and welcome to the newest episode of Kiki’s Knowledge Corner! 

Due to the recent pandemic, we have heard the word ‘vaccine’ many times.  Sometimes, even multiple times a day!  We have also visited the vaccination centres before to get vaccinated against diseases like polio.  But how many of us actually know how the vaccine works? 

That is why today we are going to learn what vaccines are and how the vaccines work.  

Let’s go!

(Click to read the section)

How does the body fight diseases?

When harmful germs enter the body, they begin to grow and spread throughout the body. It is called an infection. It causes diseases.

The immune system is responsible for protecting the body from germs like bacteria, viruses, fungi and other harmful things. When there’s an infection in the body, the white blood cells in your body help your immune system fight the infection.

The immune system needs a few days to make the tools called antibodies needed to fight a new germ. For germs that the body has already fought before, it can make the antibodies much faster. It is because it remembers every germ it has ever fought. This protection is called immunity. 

What are vaccines?

People take vaccines, which are a type of medicine, to protect themselves from diseases they haven’t had yet. Essentially, vaccines are used to prevent diseases. 

How do vaccines work?

Vaccines work by helping the immune system fight infections. Vaccines help your body fight off diseases by giving it a taste of what it’s like to be sick from a particular disease. If the disease ever attempts to make you sick for real, your body will be prepared to fight it off because of the vaccine. 

Once a person has been vaccinated against a disease like polio, measles, etc., their immune system is ready to fight the disease quickly and strongly if they ever get it. As the vaccine starts working, some individuals may get a mild fever. There’s no need to worry, as this is perfectly normal. 

Vaccination is one of the best ways to keep someone from getting a disease. But no vaccine is perfect. However, when a person is vaccinated, the chances of them getting very sick reduces.

Did you like this article? Did it help you learn anything new? Do you have any questions on vaccines? Let us know in the comments below. 

Disclaimer: This post has been overly simplified to make it easy for children (Ages 5–8) to read and understand. Kindly read the referenced material carefully for more information. 

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About the Author

“Me-kha-la!” That happens at least once when she introduces herself to new people. She wholeheartedly believes in the quote by Arthur Rubinstein that says – “if you love life, life will love you back”. She is an organizational psychologist and psychometrician. She was a class teacher of 36 adorable girls for two years, grades 2 & 3, as a part of the Teach For India Fellowship. These little girls have a special place in her heart, and when she writes for children, she writes for them!

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