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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Signs and symptoms of a drug overdose include losing consciousness, fever or sweating, breathing problems, abnormal pulse, and changes in skin color.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Asthma cases in Americans are about 75% higher today than they were in 1980.
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