What an antibiotic does
Show on a big screenA doctor says an antibiotic will not help a cold. Why not?
Bacteria and viruses are two kinds of germ. Both are too small to see by eye. Bacteria multiply: each one divides in two, again and again.
- Germs come in kinds. These are bacteria.
- These are viruses.
- An antibiotic acts on bacteria.
- It does not act on viruses.
A cold is caused by a virus. An antibiotic does not act on viruses.
An antibiotic is a medicine. It kills bacteria, or keeps them from multiplying.
The rule
Antibiotics work against bacteria. They do not work against viruses. Cold and flu come from viruses. A doctor decides if one is needed.
| Germ | Examples | Does an antibiotic act on it, on this bench? |
|---|---|---|
| Bacteria | Typhoid, cholera, tuberculosis | Yes |
| Viruses | Cold, flu, measles | No |
Watch out!
A vaccine is not an antibiotic. A vaccine trains the body's defences. An antibiotic acts on bacteria.
Only a doctor decides who needs an antibiotic. This bench is made up. A real worry goes to a parent, a teacher or a doctor.
Pick a germ. Switch the antibiotic on.
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