Thanks for your question.
Basically for successful treatment of threadworms all household members must be treated, even if they don't have any symptoms. Also you need to ensure that during treatment and for a few weeks after the treatment you need to follow strict hygiene measures to avoid spreading the threadworm eggs. Regularly vacuuming your house and thoroughly washing your bathroom and kitchen will ensure this. Personal hygiene such as keeping the nails short and washing hands regularly also is beneficial.
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