My 18month old had threadworm 4 weeks ago, we all took the medication as advised and again 2 weeks later which was now 2 weeks ago. Now last night she's showing symptoms again. We couldn't see anything this time but fidgeting and wriggling around for 2 hours last night exactly as she did when we know she had them before. We did all the cleaning and washing of bedding etc last time. She also had them in the summer, between that and last time was about 6 weeks. Both times she was back to normal at night within 48 hrs of taking the medicine. We assumed the only reason they came back after the very first time was because we didn't all take the followup dose. But last time we did, all took the repeat dose 2 weeks ago and so feeling defeated now because they seem to have returned so quickly. I literally washed all toys and the house last time, do I just do it all again for them to keep coming back?? She goes to nursery which is where we suspect its come from so I fear it never going to end.