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Vaccines prevent between 2.5 and 4 million deaths every year.
A seasonal flu vaccine is the best way to reduce the chances you will get seasonal influenza and spread it to others.
There are 20 feet of blood vessels in each square inch of human skin.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
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