I treated a little girl ( about 10 years old) for head lice. She had clumps of lice bugs and nits. I would estimate that she probably had head lice for about 1 year.
In working in the Lice Business I have heard of different head lice home remedy treatments. I've heard of dish washing liquid, mayo, vinegar, petroleum jelly and even gasoline.
If there is Head Lice going around in your family as a precautionary measure cleaning immediate bedding ( pillowcases, comforter and sheets) regularly wash them and put them in dryer for about 30 min.. if there are any Head Lice the heat from the dryer would kill them .. is the comforter can not fit in