I was trying to figure out what was wrong with one of my other chickens and came across this article(this isn't what I was looking for). But not a week later I notice it in one of my chickens. It's a crazy coincidence but we quarantined that bird. Unfortunately, it still spread to the rest of the flock but we already had the vaccine on the way. Being able to catch it quickly saved 7/8 of my flock.