The bubonic plague was a painful disease, with black buboes or swellings, in the groin and armpits, which lasted up to a week. There was some chance of surviving if the buboes burst. If the buboes burst of their own accord it was a sign that the victim might recover.
An estimated 30% to 60% of the population of Europe died from the plague. This is often referred to as the 'mortality rate'. There were different types of the disease with different mortality rates: