The article discusses the plague, in medieval times called the Black Death, and caused by the bacillus Yersinia pestis, focusing on the continuance of plague outbreaks in the 21st century. A diagram offers information on what the plague is, its symptoms and how it spreads; its history from the 6th century to 2014, with emphasis on the number of victims throughout history and attempts to eradicate it with modern medicine such as vaccinations, antibiotics, and diagnostics; and its possible use in biological warfare.