Plague doctor...the "beak" would contain herbs that would help to protect the Doctor from contracting the disease. It was basically useless...of course they didn't realize how disease was spread and the different methods of cross contamination, etc...
The Black Death, 1348 - Coming out of the East, the Black Death reached the shores of Italy in the spring of 1348 unleashing a rampage of death across Europe unprecedented in recorded history. By the time the epidemic played itself out three years later, anywhere between 25% and 50% of Europe's population had fallen victim to the pestilence.
10 things you (probably) didn’t know about the Black Death - It is one of the worst catastrophes in recorded history – a deadly plague that ravaged communities across Europe, changing forever their social and economic fabric. But how much do you know about the Black Death? | History Extra
Doctor during the plague years, an artistic depiction of their masks. "During the period of the Black Death and the Great Plague of London, plague doctors visited victims of the plague. A plague doctor's duties were often limited to visiting victims to verify whether they had been afflicted or not.