I have shingles but cannot afford a doctor's appointment right now. So I won't have a doc note. Can I just show the rash on my back to my supervisor?
No, you shouldn't go to work. Shingles is caused by the virus that causes chickenpox. Anyone who has not had chickenpox or the vaccine can get chickenpox if they are exposed to someone with shingles. My dad was in the hospital with shingles and there was a big sign on the door to his room that said, "Do not enter if you have not had chicken pox or the chickenpox vaccine."
unless you're in bad standing with attendance, why would they automatically terminate your employment for calling out with a contagious illness? I'd say they'd be thankful you didn't report to work, and risk spreading it.