I don't understand the language that the articles are written in. Symptoms: I have one 2 year old chicken with bald spots on her shoulders. The skin is very pink/red. She's been sleeping around the clock for a couple days. There have been shell-less eggs and eggs with thin shells on the ends and we have a history of soft shelled eggs happening occasionally. My problems are: They say egg drop syndrome is usually asymptomatic but I clearly have a sick bird. They say there is no treatment but you can eliminate it from your flock by identifying the infected birds. Does that mean getting rid of them? They say it's transmitted vertically. What does that mean? Are the eggs safe to eat if they have thin shells or other symptoms or what if they look like healthy eggs? I suspected cocci until I started reading about the eggs and i'm really sure this is happening. I also read that there's not much history of it in the USA, meaning to me that it's unlikely to happen in the states? If that's the case, what am I dealing with? I'm coming across contradictory information and not sure what to do now. Am I to disinfect the coop and everything? If I'm not getting rid of otherwise healthy birds, will the virus continue to spread?