Malcolm Moore in Shanghai
November 1, 2010
The Black Death had its origins in China more than 2,600 years ago and a Chinese admiral, who may have inspired the tales of Sinbad the Sailor, helped spread the disease to Africa, according to new research.
An international team of scientists, led by Dr Mark Achtman of University College Cork, studied 17 strains of Yersinia Pestis, the bacterium that causes the plague, from sites around the world.
They then used their data to draw up a common family tree, showing how the different strains had mutated, over time, from a common root. The tree shows a branch of the disease splitting off about 728 years ago, around the time the Black Death struck.
The Black Death was the middle of three great waves of plague. The first strain appeared in the sixth century during the reign of the Byzantine emperor Justinian. That plague is thought by historians to have peaked in the 14th century and killed up to a third of the population of Europe.
The third wave of plague began in China in the late 19th century, spreading along shipping lines from Hong Kong and hitting San Francisco in 1900.
All three waves have the same common ancestor, said Dr Achtman, who also speculated that bubonic plague was carried to South East Asia, India and East Africa by rats aboard the ships of Zheng He in the 15th century, the Chinese version of Captain Cook who is thought to be the inspiration for Sinbad the Sailor.
"What we know is that the bacterium evolved in China, and has been in China all the time, and seems most likely to have come out of China," said Dr Achtman.
"We do not know, however, how the Black Death travelled to Europe.
"Historical records say that it reached Italy via sailors coming from the Caspian Sea, but how it got to the Caspian we do not know."
Dr Achtman played down the possibility that the Black Death may have been carried into Europe by the caravans of the Silk Route. "Our dating suggests the plague along the Silk Route was relatively recent, probably after the Black Death," he said.
Wu Hao, an infectious disease specialist and bubonic plague expert at You An hospital in Beijing said there had been "no outbreak" of rat-born plague in China during the 14th century.
"There have been theories of China being the origin of the Black Death, but these are just theories," he said. "There is no physical evidence or accurate description on record."
Dr Achtman said a book published in China in the 1930s detailed historical records of "massive" plague infections in China around the same time as the Black Death.