I'm always intrigued by the little information that some of the parents on our school know about nits/lice and how much prejudice there is. I mentioned to a parent one day that I had treated my child for headlice and since my DD and hers had been playing/cuddling that she should check... and she gave the whole - 'my DD couldn't possibly have them because we don't brush her hair and lice live in hairbrushes', 'my son never got them', 'her hair is always clean' etc etc. She seemed to know nothing about it at all and was suggesting that my DD must be unclean!!
I tied her hair back to try and keep them away (personal choice) but when she was in reception she had them nearly all year... I checked her hair every couple of days and treated with proper stuff (occasionally), and the rest of the time combed through conditioner or hair detangler treatment! As fast as I cleared them, she got more from some other child at school. I got so fed up telling the school she had them - they didn't do anything, only occasionally send home a tiny note saying 'there has been a case of lice in your childs class, please check your childs hair', the rest of the time they made me feel like an inadequate parent!! The school never offered actual advice on how to treat or how often, so although I know because I searched hard and asked other parents, many parents at our school know absolutely nothing!
She's gone into Y1 and they play differently now so we've only had them once in the last 3 months, I'm hoping this may be the end of constantly having them!!
You get lice from hair contact. They walk along the hairs. Combing the hair with nothing in it is not effective as they move faster than you can comb. Lice live in dirty or clean hair, short or long hair. They are fairly clear but can change colour to blend with the colour of the hair they live on! The 'itch' tends to the the sign of an infestation/reaction to the bites, it is likely that if they have started itching they have probably had lice for days unnoticed!