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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
Medication errors are three times higher among children and infants than with adults.
Vaccines prevent between 2.5 and 4 million deaths every year.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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