How do Vaccines Work

by - May 06, 2020

From the outrage of watching my own home state’s struggle with anti-vaxxers to discussing how herd immunity works to my own personal experience of watching a child die of a preventable disease, I've spoken on multiple occasions about why you should vaccinate your children. A recent conversation with an online friend however brought up a curious fact that I had not noted till date - in continuously pointing out the need for vaccinations, I have never really explained HOW vaccines work, have I?

a man staring at vials

It is a good topic to address and one I feel you all need to understand so you too know what to say when someone tries to engage you in a debate. I will try to explain it in as simple a format as I can.

We will do this in two steps.

1. How does your body's immune system work?

There are groups of cells, tissues and organs in your body whose key job is to defend you against a disease. This group – ranging from tiny microscopic cells and membranes to your thymus and bone marrow - collectively form your immune system. Think of them as the watchmen. 

Now when a disease-causing germ enters your body, your immune system a.k.a. 'watchmen' instantly identify that these germs don't belong to your body. They then create special weapons called antibodies that help destroy or weaken the germs. Creating this weapon takes time and thus you will feel the effects of the disease while the weapon is still being made.

After the disease is thwarted by the weapon, the watchmen save these weapons in a cupboard in neat labelled boxes. The next time the same disease enters your body, the watchmen immediately identify it and just use the weapon faster so that you can defeat the disease before it makes you sick.

2. How do Vaccines Work?

Vaccines are cheat codes we give to our watchmen in advance. Instead of waiting for the disease to infect us, we administer killed or severely weakened versions of the disease-causing germ. Just like in the first scenario, the 'watchmen' react by again recognizing that this 'germ' does not belong to your body and then create weapons - antibodies - against the germ. 

Think of the brilliance here. Now you don't have the disease since we used killed parts of the germ and yet you've got the weapon against it (stored in a labelled box) inside your body. In the future, when you do become exposed to the disease, your watchmen will just pick up these weapons they have already prepared and defend your body rapidly, saving you from getting the worst symptoms of the sickness. 

infographic explaining how vaccines work

This is how vaccines work. This is how we eradicated smallpox – a disease which used to kill 3 out of every 10 people it infected  for centuries – in just less than 15 years. This, my dear friends, is the magic of immunity.
This is why you need to vaccinate your children.
What's #YourCareQuotient? How much do you understand your child when it comes to sleep patterns, feeding and vaccination? Take the easy, interactive quiz that guides you and get the childcare guide now. 

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  1. How simply and wonderfully explained doc! Thanks for this post. I can't imagine the logic behind the snti-vaxxers lobby.

    1. So many anti vaxxers are still there in India even today. It is okay to have doubts but even after the doubts are clarified they continue to not give their children vaccines. This can become a huge issue for the community

  2. Very well explained, doc! I will never understand the logic behind the anti-vaxxers lobby - there are some pretty well known names on there too, which I find quite surprising. You would think educated people would be able to make more informed decisions, but more often than not, you find that this isn't necessarily true!

    1. Unfortunately you're right. I've seen some popular young stars also in the recent list of those who say no to vaccines. Distressing

  3. This explains things very simply! Should help a lot of people.

  4. Thanks for making it so simple to understand. I got some idea now

  5. AnonymousMay 06, 2020

    This makes sense. Don't know why so many are still against vaccination especially after we've seen what happens when we don't have a vaccine

    1. Exactly. At least now with what corona has done across the world, people should stop pushing for an anti vaccine agenda


Let me know what you think.