Researchers estimate that thousands have died. In many cases, the precise origin of the poison has never been determined. But records and interviews show that in three of the last four cases it was made in China, a major source of counterfeit drugs.From China to Panama, a Trail of Poisoned Medicine - New York Times
What they are referring to are cases in which counterfeit medications are resulting in deaths. Many of those dying are poor people in poor countries.
What does this have to do with immigration? Well when we promote immigration from a country we are electing to become more like that country in some ways. (See this 2003 case in Florida.)Do we really want the US to become more like countries like China and India?