you do have to wash everything to make sure it's off. i find the classic sign for head lice in a child is when they scratch in the back of the neck. so if they are scratching on the top that's not as significant because lots of kids have itch at the top of the scalp. but i have found my observation has been a great clue is when they start scratching at the back and that's the time to start looking. sometimes you have to look for 10-20 minutes it's not always that they are so obvious. sometimes you have to look really hard till you see them. lots of kids have dandruff. so if it comes off easily if it flakes off chances are its just dandruff and not lice but if it's stuck to the scalp where you try to pull it off and it won't come that could be a sign of nit and that needs to be treated.
how about pillows and sheets and towels and things like that?