Define disease. (I'm literally ignorant of the term "disease" right now, I'm going to take a look).
a condition of the living animal or plant body or of one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms : sickness, malady; a harmful development (as in a social institution); trouble… See the full definition
www.merriam-webster.com
"1) a condition of the living animal or plant body or of one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms "
Hmm. No, I don't think drug addiction meets this definition.
"2) a harmful development (as in a social institution)"
No, I don't think it meets this definition either.
However, I do know that people have addictive personalities. Is this something that "impairs normal function", no.
I don't think drug addiction is a disease.
I think it's as serious issue, something that needs to be understood. I think in China or other countries where it's very difficult to get drugs to be addicted to them, people will still have addictive personalities, but that doesn't mean it will end up as a drug problem.
Some people take drugs for a variety of reasons, mostly to avoid reality.
But that isn't the point of this topic.
The point is about the source of people's method of dying.