Many plague epidemics affected Europe from the XIV to the XVIII centuries. In the XVII century, many European countries were ravaged by the plague. This happened long before antibiotics; therefore was no remedy and the diagnosis of plague was almost certainly a death sentence.
At that time, medical uniforms did not exist. The risk of contracting the infection was very high for doctors who saw, examined, and treated patients with the plague.
When in 1619, the bubonic plague reached Paris, an experienced French physician named Charles de Lorme (1584-1678) created the first medical uniform, the so-called "plague preventive costume". The medical costume consisted of an over-clothing garment (Moroccan) extending from the neck to the ankle, gloves, boots, a hat and a mask. The strange mask had an extended half-a-foot-long shape like a beak nose filled with perfume. He believed that this could purify poisonous air. The eyes were also protected with spectacles.
With this outfit, de Lorme (and soon, other physicians) could attend to patients who needed their assistance. de Lorme became a real hero, and his medical costume received much praise and recognition as his invention assisted as many people as possible.
It remains an iconic outfit and has become a staple of Italian commedia dell'arte and traditional Venetian carnival celebrations even to this day.
The illiustration was taken from public source en.wikipedia.org/wiki/Plague_doctor)