Store Banner Desktop

Store Banner Mobile

Black Death at Tourinai

Study of Black Death skeletons reveals plague may have been airborne

Getting your Trinity Audio player ready...

An analysis carried out on 25 skeletons of plague victims discovered by railway engineers beneath London last year, has revealed that the Black Death was even more lethal than previously thought. Scientists are now doubtful that the epidemic was spread by the bites of infected fleas living on rats. Instead, it appears that the pathogen mutated into a more virulent strain that was airborne.

The Black Death arrived in Britain from central Asia in the autumn of 1348 and by late spring the following year it had killed six out of every 10 people in London. It was one of the most devastating pandemics in human history, resulting in the deaths of an estimated 75 to 200 million people.

An analysis on the DNA extracted from the 14 th century skeletons unearthed in London revealed traces of Yersinia pestis bacterium, the pathogen responsible for the Black Death, confirming what scientists had suspected – the remains belonged to plague victims who had been hastily buried in a mass grave. Guided by underground radar scans, researchers now plan to expand their search for more victims as it is believed there could be hundreds if not thousands more nearby.

Traces of Yersinia pestis were found in the 14th century skeletons

Traces of Yersinia pestis were found in the 14 th century skeletons.  Photo source.

Scientists compared the strain of the plague preserved in the victims, to a strain that was recently responsible for killing 60 people in Madagascar. To their surprise, the 14th-century strain, was no more virulent than today's disease. That means that there must have been another factor that caused the 14 th-century strain to become a deadly pandemic, while the Madagascar one did not.

The findings cast doubt on the ‘facts’ that every schoolchild has learned for decades – the Black Death was caused by a highly contagious strain spread by fleas on rats.

“As an explanation for the Black Death in its own right, [bubonic plague is] simply not good enough,” said Dr Tim Brooks, an expert in infectious diseases at Public Health England. “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.”

The Black Death was one of the most deadly pandemics in recorded history

The Black Death was one of the most deadly pandemics in recorded history. Image source.

Scientists working at Public Health England have therefore suggested a different cause - for any plague to spread at such a pace it must have got into the lungs of victims who were malnourished and then spread by coughs and sneezes – fatal in medieval Europe’s crowded cities. It was therefore a pneumonic plague rather than a bubonic plague, which had a much lower survival rate and could kill within 24 hours.

“In a small number of people … the organism will spread to their lungs and they will then develop a pneumonia,” said Dr Brooks. “It is that critical switch, that if there were enough people in contact with them, that allows it to spread as a pneumonic plague.”

The results of the study have led to a breakthrough in our understanding of the ancient pandemic of the 14 th century, and offers new hope in the understanding of how plagues evolve and spread over the centuries.

Featured image: Black Death at Tourinai, 1349. Image source.  

By April Holloway



I'd never read about transmission from a pig; but I am no expert on the subject.

During the time period you are referring to & for long time prior to & afterwards, families lived either along side of or above where the animals were sheltered because the heat from the animals would rise up to where the family was, which would supplement whatever heat there might be from another source such as a fire for cooking. These animals would be whatever the family was fortunate enough to own--a pig, cow, horse, chickens, etc.

You are right about people dying from neglect. They were often abandoned to fend for themselves. In addition, any house known to have someone with the plague inside was boarded up from the outside so the residents could not leave & infect others. Some families boarded up their homes from the inside in an effort to protect themselves from others with the disease who might come seeking assistance & from individuals or groups seeking to steal, whatever they might find to carry off for themselves.

As for the swollen lymph glands or buboes, which from what I read were generally in the arm pit and the groin area, I had only read that they were terribly painful & in some cases they would burst open (when they did the person might live--depending on how strong their constitution). I never read where they were cut out, although I had wondered why they weren't if it were known that sometimes when the buboes burst the person lived.

Every survivor account I've seen said the first thing anyone noticed was a dying pig. They believed it was transmitted to the pig's handlers - then to other humans. So the airborne disease fits right in. Back in those days Mr Pig was part of the family up to the day he became part of the diet. Many homes would have a pig lot attached to the house.

Another consideration from contemporary accounts: Many people died of neglect. People were so horrified that parents headed out to the country while leaving their children in town. Same for the elderly. God help you if you got a common sniffle because nobody else would.

I once read a contemporary surgeon's account. He said victims would develop large hard masses in their lymph nodes. In rare cases where these were cut out he said the patient usually recovered.

Ed Haines's picture

Rodents are the reservoir of Yersinia pestis. The fleas transfer the bacteria to humans. This is not hypothetical but is based on a lot of study. There are a number of other diseases with similar reservoirs in wild animals. Malaria, Lyme disease, Rocky Mountain spotted fever, and others. Plague is a bit unique in that it can be transferred by flea bite or, in the pneumonic form by aerosol.

Ed Haines

          I believe that with the sanitation issues and the socioeconomic divide, the probability of the plague going air borne is very likely, and the rat transfer hypothesis does loose some of its validity.  It makes it more likely that respiratory diseases made the infection and mortality rate higher, than just the plague by itself. 



Kamil Jaruga

Ed Haines's picture

Yersinia infections occur in two manners. Sporadic infections affect one person at a time and are characterized by high fever, large lymph nodes (buboes) and a modest death rate. These are not contagious from person to person. There is overwhelming evidence that these infections result from flea bites of infected fleas that, in most cases have become infected from rodents. It is seen in numerous areas of the world including the US Southwest.


The other form of infection is pulmonary (lung). Some individuals with the bubonic form of yersinia infection develop pneumonia (lung infection of the Yersinia pestis bacteria). The sputum of these individuals is very contagious from person to person and can result in multiple cases. In the pandemics of past centuries, little was known of how to isolate such cases and control the widespread contagion. Death rate from this form of Yersinia infection is quite high, especially if not treated early and aggressively.


There is a vaccine for yersinia but it is only used in persons at risk of exposure. The US Army used to require it (I do not know if they still do). Many veterinarians receive this vaccine because of possible exposure.

Ed Haines


aprilholloway's picture


April Holloway is a Co-Owner, Editor and Writer of Ancient Origins. For privacy reasons, she has previously written on Ancient Origins under the pen name April Holloway, but is now choosing to use her real name, Joanna Gillan.

Joanna... Read More

Next article