The short answer is because they are small, don’t need a lot of food and have evolved to compete with other bacteria by growing in number faster. Lots of bacteria are great at spreading in some environments but not in others so its important to remember how important the environment is to all species. If you are interested in particular germs, bacteria, viruses or parasite I can be more specific
If you want to know about a specific germ then I can tell you some of the tricks they use to spread specifically but as they are all so different I have been about as specific as I can be 🙂
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The short answer is because they are small, don’t need a lot of food and have evolved to compete with other bacteria by growing in number faster. Lots of bacteria are great at spreading in some environments but not in others so its important to remember how important the environment is to all species. If you are interested in particular germs, bacteria, viruses or parasite I can be more specific
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