Black Death? Rats and fleas finally in the clear
Published 30/03/2014 | 02:30
Archaeologists and forensic scientists who have examined 25 skeletons unearthed in the Clerkenwell area of central London a year ago believe they have uncovered the truth about the nature of the Black Death that ravaged Europe in the mid-14th Century.
Analysis of the bodies and of wills registered in London at the time has cast serious doubt on "facts" that every schoolchild has learned for decades: that the epidemic was caused by a highly contagious strain spread by the fleas on rats.
Now evidence taken from the human remains found during excavations carried out as part of the construction of a rail line have suggested a different cause: only an airborne infection could have spread so fast and killed so quickly.
By extracting the DNA of the disease bacterium, Yersinia pestis, from the largest teeth in some of the skulls retrieved from the square, the scientists were able to compare the strain of bubonic plague preserved there with that which was recently responsible for killing 60 people in Madagascar.
To their surprise, the 14th-century strain, the cause of the most lethal catastrophe in recorded history, was no more virulent than today's disease. The DNA codes were an almost perfect match.
According to scientists working at Public Health England, for any plague to spread at such a pace it must have gotten into the lungs of those victims who were most malnourished and then spread by coughs and sneezes. It was therefore a pneumonic plague rather than a bubonic plague.
In other words, it was one in which infection is spread human to human, rather than when a rat flea bites a sick person and then bites another victim.
"As an explanation for the Black Death in its own right, it simply isn't good enough. It cannot spread fast enough from one household to the next to cause the huge number of cases that we saw during the Black Death epidemics," said Dr Tim Brooks from Porton Down, who is to explain his theory in a Channel 4 TV documentary programme, Secret History: The Return of the Black Death, next Sunday.
In support of the growing case that this was a fast-acting, direct contagion, archaeologist Dr Barney Sloane discovered that in the medieval City of London all wills had to be registered at the Court of Hustings. The documents lead him to believe that 60 per cent of Londoners were wiped out by the disease which arrived in Britain from central Asia in the autumn of 1348.
Antibiotics can today prevent the disease from becoming pneumonic.