From an article by Michelle Goldberg in The Daily Beast:
In September, when Craigslist dropped its “erotic services” section, Backpage.com, the classified advertising network owned by Village Voice Media, became the nation’s premier online sexual marketplace—and the most mainstream venue for the buying and selling of underage girls. Now The Rebecca Project for Human Rights, the group that got Craigslist to drop its sex ads, is trying to convince Backpage to do the same, and to do it before February, when activists expect a spike in sex trafficking around the Super Bowl.
From the Polaris Project's Web site:
Human trafficking is the second largest and fastest growing criminal industry in the world. Victims experience a loss of freedom and exploitation at the hands of their traffickers who buy and sell them in pursuit of profit. As a result, human trafficking is commonly known as modern-day slavery. In human trafficking situations, traffickers gain complete control over victims and force them into the labor, services, or commercial sex industry in order to generate profit from their labor and commercial sex acts. Some of the forms of violence traffickers use to control their victims include brutal beatings, rape, lies and deception, threats of serious harm or familial harm, and psychological abuse.It never occured to me that major sporting events [Superbowl, World Cup, Olympics, etc.] are seen by traffickers as lucrative business opportunities.
... Anyone can be a victim of human trafficking ... The U.S. State Department estimates that 14,500 to 17,500 foreign nationals are trafficked into the U.S. annually. The National Runaway Switchboard estimates that every year thousands of American children are lured into the trafficking industry. Both foreign national and U.S. citizen victims have been identified in cities, suburbs, and rural areas in all 50 states and in Washington, DC. They are forced to work or provide commercial sex against their will in legal and legitimate business settings as well as underground markets. Some victims are hidden behind locked doors in brothels and factories. In other cases, victims are in plain view, but the widespread lack of awareness of trafficking leads to low levels of victim identification by the people who come into contact with them ...
Much more information is available at the Polaris Project and the Rebecca Project for Human Rights.