How nurses can identify their patients who may be a victims of human trafficking

I need an introduction to my paper about Human Trafficking and Nursing. It should talk briefly about what is known about the issue, statistics, ethical principle that nurse should use, and their dilemma, how nurses can identify their patients who may be a victims of human trafficking. Please make it about 350 words. Use one professional journal not older than 5 years.

  So its pretty much the same thing but my instructor is asking for the statistics (in the us), and mostly how the nurses can recognize victims, and of course the ethical principles!