I quarantined the chickens that were sick after I noticed that whatever it is seems to be spreading quickly. Despite that, I still find yet another chicken sick every day. I've lost 2 so far. The first hen who got infected died sometime today, and a fluffy little silkie that I got from a stranger passed away as well. However, the silkie wasn't sick. He always just kinda hung out, and I noticed in the last few days that he seemed to be very light like he wasn't eating much if anything. I put him with the other quarentined chickens so I could keep an eye on him yesterday, and found him dead when I checked on them tonight. As far as 8 could tell, he wasn't sick. I'm not sure why he died. 
Some of my chickens do better than others. One of my roosters went from healthy to wheezing like he was going to die in just one day. My other brahma hen just has a puffy eye that seems to have gone down, and is otherwise fine. My wyandotte hen is still a little sick, but in better condition than some others. My chanteclers have caught it too, but they just have a little rattle and a cough so far.