Child abduction, especially in the third world is a real problem. The thing that most people don't realize is that the sex slave trade is in fact a very large criminal enterprise and there are men who get paid a lot to nab children when they are young. There are also high profile people involved in this but very few have their names revealed.
If you want to know just how big a problem this is take a look at the Catholic Church. I know its not abduction but its a problem.
We all have heard stories of women being kept in basements for years and years before they are found. How many aren't. Many are traffiked off to other parts of the world.
I wouldn't leave children with maids if I was you. I don't know if its ignorance on the part of the parents but you are essentially leaving your children with less than educated women from parts of the world where most people are not well versed in public safety.