What are the symptoms of threadworm, other than itching?

[fadingfast]

I'm not sure whether DS has worms. No visible evidence of worms (but don't really know what I am looking for). He has complained of an itchy/sore bottom and this could be because he doesn't always 'wipe' properly, but it still seems irritated even when clean. Are there any other symptoms? I am worried I might also have it as have been mildly itchy and have had a gripey/queasy tummy off and on for several days.

Wetting the bed can also be a sign.

The little blighters only come out at night, so to see them you need to look about half an hour after the dc have gone to sleep. They are like little white threads of cotton.

Picture on here of what they look like.