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Vaccines prevent between 2.5 and 4 million deaths every year.
There are more sensory neurons in the tongue than in any other part of the body.
A seasonal flu vaccine is the best way to reduce the chances you will get seasonal influenza and spread it to others.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
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