Neil Clark


We all hear the words "germ" and "bacteria" and "virus" from our earliest days.
We associate them most often with sickness, or with washing them from our hands before eating to prevent sickness. For many of us, our concept of these tiny organisms is a hodge-podge of half-truths and misinformation. Add the element of fear -- plague, cholera, polio, and HIV have terrified generations in their turn -- and you have a recipe for half-knowledge, a commodity that is marginally valuable at its best.

This lesson will try to organize some basic information about germs in common terms, which will then help us consider the relationship between germs and water. A safe water supply is an essential public health asset. So why, when diseases break out, do people sometimes investigate the local water system as a possible cause?

1 What are germs?
2 How are we exposed to germs?
3 What kind of environment do pathogens like?
4 How do germs travel?
5 Symptoms: What do we mean by sick?
6 What is water's role?
7 What can water suppliers do?
8 What are the rules?
9 Conclusion

List of
diseases and
their pathogens
Final note on  E. coli  

Lesson One

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