How Viruses Spread & Why You Should Stay Home: Explainer for Kids

Mar 17, 2020 / By Emma

Staying away from regular activities and friends is plenty stressful even for grownups, and it’s an even bigger challenge for kids to make sense of it all. By sharing the science of how viruses are transmitted, we can help kids to see staying at home as a powerful way to help keep friends and family safe, rather than as something scary or frustrating.

If you’re stuck at home right now, you’re not alone! Millions of people in the US and all over the world are canceling classes, parties, and visits to help stop the spread of a new virus. This virus causes a disease called COVID-19. For some people, this disease isn’t much worse than a cold, but it can make others very sick, and there’s no vaccine to prevent it or medicine to treat it yet. That means the best way to keep people safe is to stop them from getting the virus in the first place. Fortunately, there’s something we can all do to help: stay home!

First, let’s look at what a virus is. Viruses are teeny-tiny particles that can invade your body. They’re around 1,000 times smaller than the smallest cells (the microscopic building blocks that make up everything in your body — and all living things). Cells can eat, breathe, and make copies of themselves on their own. But viruses aren’t like that. They don’t eat or breathe, and they can’t make copies of themselves without a host cell. Here’s how it works:

  1. Someone with a virus coughs or sneezes near you, and virus particles end up in your nose or mouth
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  3. A single virus particle attaches itself to a cell in your body — the host cell. The host cell is kind of like a party host, but the party guests (the virus particles) are pretty rude!
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  5. The virus uses the host cell to make lots of copies of itself — like using a photocopier.
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  7. The new virus copies break free of the host cell and attach themselves to other cells.
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  9. The virus keeps spreading through your body — into your throat, lungs, bloodstream, and muscles (which is why you might feel achy all over).
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When a virus spreads through your body, your immune system sends out special cells to fight it off. Some of the virus-fighting cells heat up to temperatures that are too high for the virus to survive — that’s a fever! Others make more mucus or make you cough or sneeze, which help get the invaders out of your body. So the symptoms of the virus are really your body fighting for you!


One thing that’s really important to remember is that, by the time symptoms like a fever or cough show up, the virus is already there in your body — and has been for a little while. In the case of COVID-19, you could have the virus but not show any symptoms for 2–14 days. And sometimes, you might be carrying the virus and not show any symptoms at all! But during that time, you can still pass it on to other people, even if you don’t feel sick. Just think of all the places you go, the things you touch, and the people you interact with in just two days (let alone two weeks)!


That brings us to how the virus travels from person to person. When you cough, sneeze, or touch your face near your nose or mouth, you spread tiny droplets of mucus or saliva all around you. To imagine this, put a little bit of glitter in your palm and blow on it. (Outside, please!) See how far the glitter goes and how it lands on everything in front of you? Droplets from a sneeze or cough (or even just from talking) can spray 6–8 feet (over 2 meters).

Glitter, like germs, can spread all over the place. (Photo credit: Asife/Shutterstock)

Those droplets can also get on your hands (like if you cover your cough with your palm instead of your elbow) and then onto everything else you touch: door handles, railings, light switches, keyboards, phones, countertops, pens, toys, and more. If you have a virus, even if you don’t have symptoms, your virus particles end up on everything you touch, too. And then, if someone else touches one of those things within three days, the virus ends up on their hands. (That’s why it’s important to wash your hands with soap!)

Avoid spreading droplets by coughing and sneezing into your elbow, not your hands. (Photo credit: BlurryMe/Shutterstock)

The best way to keep those droplets from spreading viruses to people is to stay away from others. Staying home means you’re a lot less likely to come into contact with the virus that causes COVID-19, and if you have it, you can’t spread it very far. That keeps the virus from reaching people who would be in more danger if they got it. So by staying at home, you’re protecting your family, friends, and community. Way to go, you virus-fighting hero!


If you do have to go out, here are some things you can do to help stop the spread of viruses:

  • Keep your distance from people you don’t already live with. Try to keep at least six feet away and avoid handshakes and hugs. 
  • Make sure shared surfaces (like door handles or countertops) get wiped down with alcohol wipes or a bleach solution at least once a day. 
  • Wash your hands with soap before and after going out or use hand sanitizer if soap isn’t available. 
  • Wear a mask over your mouth and nose to keep your droplets contained. When you get back home, take off your mask and either wash it or throw it away.

Further reading for parents:

Note: An earlier version of this post recommended only wearing a mask if you have symptoms. The original version of this article was posted when there was a national shortage of masks and the CDC was not recommending masks for most people. We’ve updated to follow current recommendations.

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