In my 8 years of being a hair stylist, I have seen MANY cases of head lice come in to various salons. The best advice I can give you along with treating the the head topically, (which you have been given many excellent advice and tips on) is the ONLY way to really get rid of those little suckers is by cleaning anything and everything...
Lice LOVE carpet fibers and fabric that is a wonderful place to hatch eggs... I would shampoo carpets, rugs, mats... and vacuum
Drapes, throw pillows, and check your furniture.. they LOVE couches, loveseats and chairs.. I always recommend shampooing and vacuuming anything fabric..
Remember your bathmats too.. kitchen rugs...
And don't forget your cars..
I have also heard of success of Bug Bombs from others stylists recommendations but I am not sure what they are or what they really entail..
Just thought I would pass this info on.. People think lice jump. This is a major misconception. The only way a person can get it is from direct contact. Such has sharing, hats, scarfs, shoes, clothes, hats, combs, brushes..
Also Hugging someone may pass it on... may not necessarily because you HUG someone who has it but because they are on their clothes. Because you hug someone and your clothes do touch, this is how they will pass...
I would also check every head, in your house, even your own.. all it takes is sharing the same pillow or laying on the floor.. If someone has it in your house, there is a 99% chance everyone has it.. The best you can do is treat everyone...
I am sure you already knew this but I thought I would pass it on.. I studied them quite intensively in school and many extra education classes. I have also looked at a few under a microscope.. nasty little bugs...
Hope this helps
Good Luck