In western and northern areas of the South American continent, there is less security in general and more poverty. Colombia, Peru, Ecuador, and Bolivia all have serious political and economic problems. In this kind of environment, human trafficking is easier for those who profit from it. There is a ready supply of poverty-stricken people to victimize with promises of jobs out of the country, and those transported to Europe or the United States are less likely to escape home than those from Mexico.
Also, in these same countries exists a persistent and well-organized, heavily armed system of drug traffickers. So smuggling networks out of these countries and into wealthier countries are already established, and human trafficking can take place with relative ease and high profit. Colombia and the Dominican Republic have much higher rates of human trafficking than Ecuador, however.