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Vaccines – What are they and why do we need them?

Team StoryWeavers|November 11, 2020, 06:14 IST| 10

What ends a pandemic? Vaccines!

The novel Coronavirus, which is behind the COVID-19 pandemic, has taken the whole world by storm. Offices, schools, malls, gyms, and every non-essential place is shutdown in nearly every corner of the world. Just so that we can fight this virus better. Close to 3 billion people around the world are under lockdown. That’s almost half the world’s population. Governments across the globe are taking measures to prevent the spread. Experts say that our best bet to slow the spread of the virus is to practise to social distancing and maintaining proper hygiene. 

Meanwhile, everybody is talking about a vaccine that can stop the coronavirus once and for all. So why haven’t we invented a vaccine yet? And how do vaccines help prevent pandemics in the first place? Let’s take a look at some of these questions.

Vaccines are given through either an injection, orally (like Polio drops) or sometimes even nasally.

What are Vaccines?

Vaccines are one of the most effective and sometimes the only way to prevent certain diseases from happening to us humans. The process of getting a vaccine is called Vaccination. Vaccination is the process of introducing the immune system to a weakened form of an infection, which later helps the immune system to develop a fighting mechanism against the real infection. 

Vaccines are given through either an injection, orally (like Polio drops) or sometimes even nasally. As of today, the World Health Organization(WHO) reports a total of 25 licensed vaccines like Penicillin-G, MMR, etc, that are available for the prevention of 25 respective diseases including Scarlet Fever, Measles, and Rubella. Vaccines are so effective at stopping epidemics from spreading that they have almost entirely eliminated many deadly diseases from the world like Polio, Influenza, Typhoid, and Tetanus. 

How do Vaccines work?

Vaccines are nothing but a less potent, inactive or sometimes dead form of the very infection that it is meant to prevent us from. Our body responds to these weakened germs by producing its own fighting mechanism called antibodies. These antibodies stay in our blood for a long time and get activated any time the actual germs enter our body. So when the vaccine enters your body, it familiarises your immune system with the dangerous viruses and bacteria, to which your immune system responds by developing a fighting mechanism.

So for example, when someone is given a vaccine for Polio, they are given a very weak form of the virus. Since the virus/bacteria given in the form of the vaccine is not very strong, our immune system develops antibodies for Polio. So that later if our body contracts the virus/bacteria again, the immune system already has the antibodies to fight back. This process is called immunization. 

Antibodies made by immune system helps fight off the bacteria or virus that attacks our bodies

When do you get vaccines?

Every country has its own schedule planned for the vaccination of its citizens. So everyone compulsorily gets some vaccines, depending on which country they belong to. For example, every citizen of India takes a total of 13 vaccines since their birth. The list of compulsory vaccines of each country depends on the type of infections that area is prone to. Most of the vaccines are given to people at a very young age ranging from within a week of birth to up to 16 years of age. 

And then there are some vaccines which are taken by people regardless of their age. It is based on need. Like for example certain viruses like influenza upgrades/mutates itself on an average of 6 months to a year, which means if you took a vaccine for flu/common cold now, there’s a good chance it will no longer be effective a year from now. So next year again, you will have to take a flu shot. But usually, our bodies are strong enough to fight back influenza, hence many people don’t take this vaccine.

Why don’t we have a vaccine for COVID-19 yet?

To answer this question, we will have to understand the steps of making a vaccine. Broadly there are three steps to making a vaccine:

  1. Isolating the virus/bacteria from the host’s DNA. Collecting them in the purest form, in order to understand and test it.
  2. Developing the Vaccine
  3. Testing the Vaccines through clinical trials

All of these steps happen inside medical research labs, performed by highly trained doctors and scientists. Needless to say, the process of making a vaccine is extremely complicated and time-consuming. The Novel Coronavirus is a very new type of virus for mankind and scientists just finished decoding its entire RNA. Every step in the process will take its own time. And this is the reason why no country has been able to develop a vaccine yet. But clinical trials are underway in some parts of the world and the best minds are on the case. 

Meanwhile what can prevent the virus from spreading is practise social distancing. Staying inside our homes, avoiding meeting people and maintaining high standards of personal hygiene is the best we as individuals can do right now to contain the spread of this dangerous disease.

So stay home, stay safe and keep learning.

If you enjoyed reading this article, you may also enjoy:

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10 scientific discoveries that changed the world in the last decade

About the Author

Charu, a feminist and an accidental writer, is yet to master the art of writing about herself. Always curious to learn new stuff, she ends up spending a lot of time unlearning the incorrect lessons. She enjoys all sorts of stories – real, fictional, new, old, hers and would love hearing yours too. Feel free to ping her at to share anything that you think is worth sharing.

Leave a Comment




May 21, 2020

Great!! Vaccines are really very useful
Stay home Stay safe

Priyamvada .P. Mahapatra

May 9, 2020

Thanks for information . It was great !! I hope every body are safe in there house..


April 16, 2020

Very usefull. I request everyone to stay safe in their houses to prevent coronavirus and take the precautions revealed from the government.


April 12, 2020

It was great !! And I just hope that our intelligent and
Superb scientists and doctors will soon be able to make the vaccines of this deadly virus and we’ll again be back but it can take time so till then Stay home Stay Safe !!!

suraj kandhare

April 10, 2020

Thank you very much it was very wonderfull

Trrishan Saha

April 9, 2020



April 8, 2020

Thanks it was really helpful. And I request others to stay safe at home and enjoy this only time with parents and learning.


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