Nhs doesn't say change every day but to wash when first treated.
The lifespan of threadworms is approximately six weeks, so it's important that hygiene measures are followed for at least this length of time. Everyone in the household must follow the advice outlined below.
wash all night clothes, bed linen, towels and soft toys when you'refirst diagnosed– this can be done at normal temperatures, but make sure the washing is well rinsed
thoroughly vacuum and dust the whole house, paying particular attention to the bedrooms– this should be repeated regularly
carefully clean the bathroom and kitchen by damp-dusting surfaces and washing the cloth frequently in hot water– this should be repeated regularly
avoid shaking any material that may be contaminated with eggs, such as clothing or bed sheets– this will prevent eggs being transferred to other surfaces
don't eat food in the bedroom– you may end up swallowing eggs that have been shaken off the bedclothes
keep your fingernails short–encourage other members of your household to do the same
discourage nail-biting and sucking fingers–in particular, make sure children don't suck their thumb
wash your hands frequently and scrub under your fingernails–it's particularly important to do this before eating, after going to the toilet, and before and after changing your baby's nappy
wear close-fitting underwear at night and change your underwear every morning
bathe or shower regularly– it's particularly important to bathe or shower first thing in the morning: make sure you clean around your anus and vagina to remove any eggs
ensure everyone in your household has their own face flannel and towel– don't share towels
keep toothbrushes in a closed cupboard and rinse them thoroughly before use