Plague as a Biological Weapon

Three well-documented plague pandemics have occurred in the past two millennia, resulting in more than 200 million deaths and great social and economic chaos (Perry and Fetherston, 1997; Pollitzer, 1954). The Justinian pandemic arose in northern Africa in the mid-6th century, and by the 7th century had spread throughout the Mediterranean and near-eastern regions—severely impacting both the Roman and Byzantine empires. The second pandemic, the Black Death or great pestilence, originated in Central Asia, was carried to Sicily in 1347 via ships from the Crimea, and rapidly swept through medieval Europe. By 1352, it had killed 30% or more of afflicted populations, slowly playing itself out in successive epidemics, including the Great Plague of London in 1665 (Perry and Fetherston, 1997). The third (Modern) pandemic began in southwestern China in the mid-19th, struck Hong Kong in 1894, and was soon carried by rat-infested steamships to port cities on all inhabited continents, including several in the United States (US) (Link, 1955; Pollitzer, 1954). By 1930, the third pandemic had caused more than 26 million cases and 12 million deaths. Plague in these three pandemics was predominantly the bubonic form, emanating from Yersinia pestis-infected rats and fleas, although terrifying outbreaks of the more virulent person-to-person spreading pneumonic form were recorded during the course of each. The explosive contagiousness and severity of pneumonic plague was most completely documented in Manchurian epidemics in the early 20th century, which involved tens of thousands of cases, virtually all of them fatal (Wu, 1926).