ADDICTION EPIDEMIC The power of opioid dependence sends growing numbers of people to street drugs and deadly chemical mixes.
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TOUGH BITE Deer ticks are now spreading a new species of bacteria that causes Lyme disease.
BUYBACK In 1996, Australia initiated a program to purchase and destroy certain types of long guns, including semiautomatic weapons. Over the next four years, the country collected more than 650,000 guns.