Maybe the weather has someting to do with it. No local vets around here deal with chickens. I'm still reading information from other sites and guessing. Many of the possible causes sound the same. I'm getting most of the information from Miss. State.
Lets hope it is soon over.
To get back to normal, some people recommend electrolytes in the water for 5-10 days after stress or illness. Cjeanr, I tried adding the electrolytes to the water. I really can't tell if it is doing any good,but it can't hurt. I think it was most likely the white silkie's egg. It was on the floor of the hen house.