Rats Not Responsible for Black Death After All

The book, titled “The Black Death in London,” bases this conclusion on records from the Court of Hustings of wills that were made and then enacted during the plague years. As the disease gripped during late summer and fall, the number of wills soared as panic-stricken wealthy citizens realized their deaths were probably imminent. As many wills were being made in a week as in a normal year; usually they would only be activated months or years later, as in the worst weeks of the plague, there was barely time to get them written down.

Money, youth, and robust good health were no protection from the plague. According to the records, there was little difference in mortality rates between rich and poor, since they lived so close to each other - the plague spread from person to person in the crowded city. King Edward III's own daughter, Joan, sailed for Spain with her trousseau, her dowry, and her bridesmaids, to marry Pedro, heir to the throne of Castile; she would never see her wedding day as she died of the plague within 10 days of landing.

Mortality continued to rise throughout the bitterly cold winter, when fleas could not have survived, and there is no evidence of enough rats. Black rat skeletons have been found at 14th century sites, but not in high enough numbers to make them the plague carriers. In sites beside the Thames River, where most of the refuse was dumped and rats should have swarmed, and where the sodden ground preserves organic remains excellently, few black rat remains have been found.

“The evidence just isn't there to support it; we ought to be finding great heaps of dead rats in all the waterfront sites but they just aren't there,” explained book author Barney Sloane, PhD, previously a field archaeologist with the Museum of London. “The evidence I've looked at suggests the plague spread too fast for the traditional explanation of transmission by rats and fleas. It has to be person to person – there just isn't time for the rats to be spreading it.”

The Black Death was one of the most devastating pandemics in human history, peaking in Europe between 1348 and 1350. It is widely thought to have been an outbreak of plague caused by the bacterium Yersinia pestis, an argument supported by recent forensic research, although this view has been challenged by a number of scholars. Thought to have started in China, it travelled along the Silk Road and had reached the Crimea by 1346, from there spreading throughout the Mediterranean and Europe. The Black Death is estimated to have killed 30% to 60% of Europe's population, reducing the world's population from an estimated 450 million to 350-375 million by 1400. This has been seen as having created a series of religious, social, and economic upheavals, which had profound effects on the course of European history.

Related Links:
The Black Death in London
Museum of London