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Did you know?

Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.

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According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.

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Everyone has one nostril that is larger than the other.

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There are more nerve cells in one human brain than there are stars in the Milky Way.

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There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.

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