When the bite starts to itch, the chigger is no longer there, it is gone. In fact, they fall off very easily when you take a bath. They bite the skin and don't burrow like a tick because they survive on skin fluids, not blood. You are not killing anything with the home remidies. What nail polish does is seal the area off from the air which keeps it from itching so much. So salves or creams with antihistimines will do the same thing with the addition of reducing the swelling. I have had luck with Preperation H cream and even the wipes.