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Vaccines prevent between 2.5 and 4 million deaths every year.
There are more bacteria in your mouth than there are people in the world.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.
The average adult has about 21 square feet of skin.
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