Yersinina pestis is a Gram-negative, rod-shaped, faculatively anaerobic bacterial species in the family Enterobacteriaceae. It causes bubonic plaque, which is transmitted by rodent fleas. Historically known as the "Black Plague", this disease devastated Europe and Asia in the 1300s. It still exists today, and is characterized by sudden high fever, chills, excessively swollen and tender lymph nodes (buboes), followed by tissue bleeding and gangrene. Other complications include pneumonia and septicemia.