Hi all... PLEASE can anyone tell me why my 9yo keeps getting threadworm. We are a very clean family. I am super OCD when coming to manage 'a dose', I boil wash, clean and wipe EVERYTHING and she removes clothes and showers actually in the shower each morning for 3 days after treatment, and sleeps in pj bottoms etc. We treat all the family each time and wash/change all beds, towels and clothes and wipe around then vacuum (its like a military operation each time!!). The 9yo is very hygienic, she always washes her hands and scrubs under her nails after going to the loo, 1 or 2, without being asked, she doesn't pick her nose or scratch her bum as she knows this can spread germs.... why the hell would we have at least 4 doses a year... Please HELP! I find it so disgusting and I'm sick of it happening. Thanks all in advance.