<P> People potentially infected with the plague need immediate treatment and should be given antibiotics within 24 hours of the first symptoms to prevent death . Other treatments include oxygen, intravenous fluids, and respiratory support . People who have had contact with anyone infected by pneumonic plague are given prophylactic antibiotics . Using the broad - based antibiotic streptomycin has proven to be dramatically successful against the bubonic plague within 12 hours of infection . </P> <P> The first recorded epidemic affected the Eastern Roman Empire (Byzantine Empire) and was named the Plague of Justinian after emperor Justinian I, who was infected but survived through extensive treatment . The pandemic resulted in the deaths of an estimated 25 million (6th century outbreak) to 50 million people (two centuries of recurrence). The historian Procopius wrote, in Volume II of History of the Wars, of his personal encounter with the plague and the effect it had on the rising empire . In the spring of 542, the plague arrived in Constantinople, working its way from port city to port city and spreading around the Mediterranean Sea, later migrating inland eastward into Asia Minor and west into Greece and Italy . Because the infectious disease spread inland by the transferring of merchandise through Justinian's efforts in acquiring luxurious goods of the time and exporting supplies, his capital became the leading exporter of the bubonic plague . Procopius, in his work Secret History, declared that Justinian was a demon of an emperor who either created the plague himself or was being punished for his sinfulness . </P> <P> In the Late Middle Ages (1340--1400) Europe experienced the most deadly disease outbreak in history when the Black Death, the infamous pandemic of bubonic plague, hit in 1347, killing a third of the human population . Some historians believe that society subsequently became more violent as the mass mortality rate cheapened life and thus increased warfare, crime, popular revolt, waves of flagellants, and persecution . The Black Death originated in Central Asia and spread from Italy and then throughout other European countries . Arab historians Ibn Al - Wardni and Almaqrizi believed the Black Death originated in Mongolia . Chinese records also showed a huge outbreak in Mongolia in the early 1330s . Research published in 2002 suggests that it began in early 1346 in the steppe region, where a plague reservoir stretches from the northwestern shore of the Caspian Sea into southern Russia . The Mongols had cut off the trade route, the Silk Road, between China and Europe which halted the spread of the Black Death from eastern Russia to Western Europe . The epidemic began with an attack that Mongols launched on the Italian merchants' last trading station in the region, Caffa in the Crimea . In late 1346, plague broke out among the besiegers and from them penetrated into the town . When spring arrived, the Italian merchants fled on their ships, unknowingly carrying the Black Death . Carried by the fleas on rats, the plague initially spread to humans near the Black Sea and then outwards to the rest of Europe as a result of people fleeing from one area to another . </P> <P> The plague resurfaced for a third time in the mid-19th century . Like the two previous outbreaks, this one also originated in Eastern Asia, most likely in Yunnan Province of China, where there are several natural plague foci . The initial outbreaks occurred in the second half of the eighteenth century . The disease remained localized in Southwest China for several years before spreading . In the city of Canton, beginning in January 1894, the disease killed 80,000 people by June . Daily water - traffic with the nearby city of Hong Kong rapidly spread the plague there, killing over 2,400 within two months . </P>

What was the host animal of the black plague