Bubonic

Bubonic plague is a zoonotic disease, circulating mainly in fleas on small rodents, and is one of three types of bacterial infections caused by Yersinia pestis (formerly known as Pasteurella pestis), that belongs to the family Enterobacteriaceae. Without treatment, the bubonic plague kills about two thirds of infected humans within four days.

The term bubonic plague is derived from the Greek word βουβών, meaning "groin". Swollen lymph nodes (buboes) especially occur in the armpit and groin in persons suffering from bubonic plague. Bubonic plague was often used synonymously for plague, but it refers specifically to an infection that enters through the skin and travels through the lymphatics, as is often seen in flea-borne infections.

Bubonic plague—along with the septicemic plague and the pneumonic plague, which are the two other manifestations of Y. pestis—is commonly believed to be the cause of the Black Death that swept through Europe in the 14th century and killed an estimated 25 million people, or 30–60% of the European population.[1] Around the Mediterranean Region, summers seemed to be the season when the disease took place. In northern Europe, the disease had its most frequent outbreaks in the autumn.[2] Because the plague killed so many of the working population, wages rose with the demand for labor. Some historians have seen this as a turning point in European economic development.[3][4]