I WAS FORCED TO SLEEP WITH 30 MEN IN A DAY

HUMAN TRAFFICKING SURVIVOR: HOW I WAS RAPE 43,200 TIMES...

Mexico City: Karla Jacinto is sitting in a serene garden. She looks at the ordinary sights of flowers and can hear people beyond the garden walls, walking and talking in Mexico City.

She looks straight into my eyes, her voice cracking slightly, as she tells me the number she wants me to remember -- 43,200.

By her own estimate, 43,200 is the number of times she was raped after falling into the hands of human traffickers.

She says up to 30 men a day, seven days a week, for the best part of four years -- 43,200.

Her story highlights the brutal realities of human trafficking in Mexico and the United States, an underworld that has destroyed the lives of tens of thousands of Mexican girls like Karla.

Human trafficking has become a trade so lucrative and prevalent, that it knows no borders and links towns in central Mexico with cities like Atlanta and New York.

U.S. and Mexican officials both point to a town in central Mexico that for years has been a major source of human trafficking rings and a place where victims are taken before being eventually forced into prostitution. The town is called Tenancingo.

Tenancingo, Mexico: A breeding ground for traffickers 04:47

Even though it has a population of about 13,000 it has an oversized reputation when it comes to prostitution and pimping, says Susan Coppedge, who is now the U.S. State Department's Ambassador at Large to Combat Human trafficking, and previously worked at the U.S. Attorney's office in Atlanta. 

"That's what the town does. That is their industry," Coppedge says. "And yet in smaller, rural communities the young girls don't have any idea that this is what the town's reputation is, so they are not suspicious of the men who come from there. They think they have got a great future with this person. They think they love and it is the same story of recruitment every time."