Okay, I rang the doctors.

He said he may not have it at all, and that he would not be contagious yet if he does. He said if the pregnant mums have had chicken pox they will be fine, but I don't know whether they have, and have no contact info for them or the organiser

His immunisation is due on Saturday, which is also around when he would start to be contagious if he has it, so I don't really want to take him to the council immunisations now!

I think I am going to get them done tomorrow (we can get ours on tuesdays, thursdays or saturdays) and miss out on playgroup unless I can contact the pregnant mums.

I am happy to follow the 'he's not contagious yet' advice from my GP for kids, but not for the pregnant mums, I just couldn't live with that if anything happened.