I too keep my turkeys and chickens together but I'm able to free range my birds so they only are enclosed during the nightYou can find out if your area has blackhead thru your local extension office.
I keep turkeys and chickens in the same pen and brooder when they are babies.
To my knowledge my turkey haven't given my chickens any thing.
But I think I lost some turkeys because of chickens. Mainly cocci.