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Thyroid conditions may make getting pregnant impossible.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
Vaccines prevent between 2.5 and 4 million deaths every year.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
The human body produces and destroys 15 million blood cells every second.
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