1How a germ actually gets into you
A germ needs a door — and a block only shuts one door
You only need two ideas. Watch each one:
Germs come in through doors
A germ can't beam into you. It needs a way in. The two big doors: your hands touching your face after you touch something, or tiny droplets floating in the air that you breathe in.
A block shuts one door
Each block covers just one door. Washing your hands shuts the touch door. A mask, fresh air, or standing back shuts the air door. Shut one and the other is still wide open.
2Two kinds of germ
The hitchhiker vs the floater
Germs don't all travel the same way. Each one has a favorite door:
The hitchhiker
Hitches a ride on hands and doorknobs. It needs you to touch something, then touch your face.
The floater
Rides out on a cough and floats across the room, waiting to be breathed in — no touching needed.
3Your turn — let a germ loose in a room
Pick a germ and watch it spread with nothing blocking it
Here's a crowded room. One person starts sick. Pick which germ it is, then let the room mix — and watch who catches it. No blocks yet; just see how it travels.
4Now try to stop it — shut one door
This germ travels by air. Can super-strict handwashing alone stop it? 🚪
Same room, but now you get to slam one door shut while the germ tries to spread. Guess first — then run it and watch.
Guess before you shut the door
An air germ is loose — it spreads by floating droplets. Everyone washes their hands super strictly (the touch door is slammed shut). Does that alone stop the outbreak?