I'm not dead yet!
Not a big deal except for the poor principals. Plague is a bacterial disease (Yersinia pestis) that is endemic in the Western United States. It comes in three forms depending on the site of infection: bubonic (lymph system), septicemic (blood) and pneumonic (lungs) - same organism, same disease. The pneumonic form is very contagious, spread by coughing. The bubonic form is principally spread by the bites of infected fleas. Septicemic is largely a break in the skin.
You treat it with tetracyclines, for one, but you have to be careful - the toxin is actually part of the interiors of the cell walls of the organisms, so if you kill them all at once with antibiotics you can actually make the fever and other symptoms worse, killing the patient by curing him. Bummer.
Out-west kids know not to pet dead prairie dogs, but the occasional Greenie might not be quite that well-informed...
The nusery rhyme covers it all:
Ring around the rosey (Praying the Rosary)
Pocket full of posey (The pomander of aromatic herbs to ward off the bad air)
Ashes ashes (originally atchoo atchoo, the sneezing followed quickly by...)
We all fall down (dead)
Prayer and poseys were the best religion and science had to offer. They weren't enough.
BTW, Death followed the coughing episodes so quickly that there wasn't time to summon a Priest to perform the last rights. Only a Preist was allowed invoke God's blessing. The Pope changed this to allow a lay Christian to bless someone when they coughed so they wouldn't die without a final blessing...