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Asthma cases in Americans are about 75% higher today than they were in 1980.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
Your heart beats over 36 million times a year.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
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