When you've got nothing left to sell, sell your blood. That's how many people in China, most notably in Henan, got AIDS. But as long as there's poverty, you can bet that there will be people willing to sell their own blood. In the town of Jieyang in Eastern Guangdong province, a recent expose lead to greater media attention, which meant that the authorities actually had some work to do. An investigation started, which lead to the suspension of three officials (pending further investigation) as well as the arrests of the blood-selling mafia's ringleaders (both reports in Chinese).
According to this report (in Chinese), this phenomenon has been going on for as long as 20 years. Furthermore, there are two "gangs," one from Jiangxi province and one comprised mostly of Anhui province people. The people selling blood are, to no one's surprise, poor and unemployed. They sell 400ml of blood for 200 RMB, of which the blood pimps get 40 RMB. They do this perhaps up to 15 times a month, or every other day. Obviously, that's not good for you, and the video report above shows us some of the effects of this. They can make around 1500 RMB a month this way (though it should add up to more if it's 160*15), and the ringleaders can make several thousand RMB (around 3000-4000), or in some cases, much more, selling this blood. In the video report, the journalist calls up the health bureau at Jieyang, and the person answering the phone says "we have never heard of such phenomenon, but if you have, please give us a tip and we will try to lawfully deal with these problems." And of course, like most spokesmen, they are paid to lie and sometimes aren't even good at it.

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