[Source:  CDC]

Students diagnosed with live head lice do not need to be sent home early from school; they can go home at the end of the day, be treated, and return to class after appropriate treatment has begun. Nits may persist after treatment, but successful treatment should kill crawling lice.
Head lice can be a nuisance but they have not been shown to spread disease. Personal hygiene or cleanliness in the home or school has nothing to do with getting head lice.

Both the American Academy of Pediatrics (AAP) and the National Association of School Nurses (NASN) advocate that “no-nit” policies should be discontinued. “No-nit” policies that require a child to be free of nits before they can return to schools should be discontinued for the following reasons:

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