You don't quote any sources. I'm inclined to take such reports with a pound of salt. Yes it is scary, but if we don't know for sure it is happening, the thing to do is to have the authorities investigate.
I've read in Parade magazine that there was a mental hospital in South America that had a surprisingly high rate of people released back into the community. When the authorities went to check why, they found that there were a lot of bodies buried around the grounds. On most of them, the corneas (eye parts) were removed.
I've heard the stories about people waking up to find their kidneys were missing, but I've never heard a credible first-person account.
I've also head that poor people in places like India may sell a kidney for $10.000 (enough for them to live out their lives in comfort). You can't do that in America, but the laws are different there. You can live with just one kidney.
And of course, recently we heard of the scandal where tissues and bones from cadavers contaminated with diseases were sold to hospitals and some people got hepatitis from that. That is horrible and sad, and I hope the ones responsible are caught and put in jail. I hope that something can be done for the poor peope who are sufering with these diseases now.
In the 1960's Larry Niven predicted that this would be happening. He called such people 'organleggers' after the bootleggers of old, people who made illegal alchol. His thought was that you can't stop people from wanting to live longer, especially the wealthy. Especially the elderly. Especially the wealthy, elderly legislators who make the laws on what medical advances are to be used and how.
In the early 1980's we had a narrow escape. One of the New England states, either Vermont or New Hampshire, was concerned about prison overcrowding and came up with a plan to reduce it. This was in the newspapers of the day, and you can probably find something about it in the library.
The Red Cross was having a critical blood shortage in those days. The idea was to give a prisoner time off for every pint of blood donated. You can donate once every ninety days; and a prisoner would get a month off. So a prisoner could donate three times during a one-year prison sentence and get out after nine months (getting the other three months off.)
The public didn't know of AIDS, then. The plan was not put into practice, but we narrowly missed having our blood supply infected with that and other disease that are statistically much more prevalent in prisons than in the general population. For example, there are something like six kinds of hepatitis, and there is a prison in Massachusetts that was the world capital for four of them. I don't believe that it is only poverty or poor cleanliness practices inside the prison that spread them.
We should be careful that human ghouls do not prey on the rest of us, but please be careful to check your sources and don't cry wolf.