We have never had them Neil ds 1 started school a few years ago. He was complaining of an itchy bottom which I assumed was poor bum wiping as he was in foundation. We were having to treat him every 3 to 4 months he was the only one with symptoms. Now he is older and in another part of the building he has been fine and clean for 6 months!!! However ds 2 has now started in foundation and complaining of an itchy bottom :-/. It is do time consuming and expensive. The toilets in the younger classes always stink I am sure the are not cleaned properly.