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Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
There are 20 feet of blood vessels in each square inch of human skin.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
There are more bacteria in your mouth than there are people in the world.
Asthma cases in Americans are about 75% higher today than they were in 1980.
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