Lesson 2 of 16
How an illness spreads
Show on a big screenHow does an illness get from one living thing to another?
Step 1 of 4
- Three joined links: Germ, a step, Next.
- The middle link is cut.
- The walk stops at the gap.
- Cut one link. Nothing arrives.
A germ travels by air, water, food, touch or an insect. Each way is a route.
A pathogen is a germ that causes disease. A disease that spreads from one living thing to another is communicable.
The rule
A pathogen is a germ that causes disease. It has to travel from one living thing to another. It travels by air, water, food, touch or an insect. Each route is a chain of steps. Cut one step and that route stops.
A germ needs every step. So a germ stopped at one step cannot finish that route.
| Route | Starts at |
|---|---|
| Air | An uncovered cough or sneeze |
| Water | Water poured into an open pot |
| Food | Food left uncovered |
| Touch | An unwashed hand on a latch |
This bench is made up. A real worry goes to a trusted adult or a doctor.
Pick a route. Cut it. Then pick another.
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