Did Rats Cause The Black Death?

Rats, though often criticised by man-kind, are actually quite affectionate and social animals, both towards their owners, as pets, and as comrades in the company of their fellow kind.

For centuries, on paper, and in the minds of the people, rats have been guilty of causing the Black Death.

However, new studies indicate that something a little bit closer to home than rats could be the main source of spreading Black Death.

What Is The Black Death?

Hundreds of years have passed since the deadly pandemic now known as the Black Death scoured Europe, Aisa, and Africa, killing millions of people. And, for all of this time, people have blamed rats for carrying and spreading the disease through the fleas that infected them. Scientists thought that the fleas would then jump from the rats and eventually bite humans.

Technically speaking, the Black Death was a Bubonic plague; one mainly believed to be spread by rodents and small animals normally considered a pest (such as rats). Once bitten by an infected flea, the plague would use lymphatic vessels to travel to a lymph node. The disease could also be spread by coming in contact with the sick and infected as well as the dead. The symptoms of this Bubonic plague included headaches, vomiting, fever, and painful swollen lymph nodes. 

At any rate, who, or whatever,initiated it, the Black Death killed anywhere from 30 percent to 90 percent of those whom it infected as it spread through Europe, Asia, and Africa. There is no precise and accurate death-toll recorded, but it is believed that somewhere between 50 and 200 million people may have perished from the Black Death.

But, did rats really, actually, factually, cause the Black Death? Scientists now may think “not.”

Did Rats Cause The Black Death?

The Black Death is widely believed to have bubonic plague caused and spread by filthy disease ridden rodents such as the common black rat found throughout much of Europe and other parts of the world affected by the Black Death. That said, the exact scientific or biological cause and the origin is still officially undetermined. 

However, after close examination it’s now clear that the plague was more likely spread by biting and blood sucking little pests such as fleas carried by rodents (and humans) than the animals themselves. 

Medical knowledge in the Medieval Age was not so great, to say the least. By today’s standards it was a hideous mess. The standards of living, and general health, were not very high either and parasites and bacteria thrived in the filthy environment. These are just a few of the reasons that make it plausible that humans themselves helped to spread the Black Death more so than rodents such as mice and rats as people of the time believed.

Rats, by any means, are vastly cleaner animals than public opinion, caring and grooming for members of their pack for several hours each day.

And, that is one fact that lends sustenance to the new claim that humans, as crude and unclean as they were in medieval times (individually as well as living conditions in cities in general), may have had more responsibility for spreading the plague than rats.

Why Are Rats Blamed For The Black Death?

Rats, especially in the days gone by when their numbers in the city streets and homes of the citizens were much higher than now, were seen as unclean rodents and carries of disease and the direct cause of bad health. Today, many people still view rats the same way, and in some places, such as Dubai or New York City, rat packs are still a major issue. 

Why people blamed the rats for the Black Death is quite clear, due to their lack of medical knowledge and scientific understanding. Believing rats living in filth had become affected and caused this outbreak, and spread it as well. Unfortunately for rats, we are now finding that this may not be the case at all. That humans may be the culprits, and not those dirty rats after all.

Research Indicates Humans (Not Rats) Caused The Black Death

A study published back in January of 2017, in the Proceedings of the National Academy of Sciences, by the University of Oslo, with a focus on simulating Black Death outbreaks in European cities, gave new insight to whether or not rats caused the black death. That said, it’s not the first study to claim that humans may have had a bigger hand in spreading the disease than rats did.

The university’s study looked at three main methods of infection including airborne transmission, fleas and ticks, and of course, rats. For some, their findings may be surprising.

The computer models carried out by the researchers suggested that the initial outbreaks of the Black Death were much more likely to have been caused by a combination of humans, fleas, and lice, than by rats. 

The team ran nine models based on verified plague data from Europe between the 14th and 19th centuries. Seven out of the nine models indicated humans and lice rather than rats and fleas or airborne transmission.

In their paper, the researchers said: “While it is commonly assumed that rats and their fleas spread plague during the Second Pandemic, there is little historical and archaeological support for such a claim. Here, we show that human ectoparasites, like body lice and human fleas, might be more likely than rats to have caused the rapidly developing epidemics in pre-Industrial Europe.”

At any rate, it is safe to say that the way future generations look at what caused the Black Death is likely to change, forgiving rats and putting the blame where it really lies, which, unfortunately, is on us, and those pesky little blood suckers, fleas and lice.

Interesting Rat Facts

Now that we’re learning that we might actually be the ones responsible for the Black Death, and that rats were never guilty, we may need to reevaluate and readjust our opinions of the species. 

With that in mind, we put together a few interesting rat facts for you to read below.

  • Rats are compassionate. They are much more caring than given credit for by humans and tend to their sick and injured
  • Rats have excellent memory capabilities. Once they remember something, they rarely forget it.
  • Rats are less likely to spread disease than cats and dogs.
  • Rats are prone to peer-pressure. Just like humans, rats will give in to pressure from their peers.
  • Rats tails are multipurpose. Rats use their tails for balance, communication, and for body temperature regulation.
  • Rats get lonely. If left alone without an owner or other rats for companionship, rats become depressed and lonely.
  • Rats can go days without drinking water.
  • Rats show their happiness. When rats are happy, their teeth grind and they are known to make a chattering noise. This may be accompanied by vibrating eyes. 
  • Rats can laugh. When rats are happy, and playing, they tend to make a laughing sound.
  • Rats are very well groomed. Rats spend up to several hours grooming themselves and other group members daily.

Final Thoughts

It is not precisely clear, other than their curiously dirty appearance and scavenger-like behavior, where the belief that rats caused the Black Death even came from to begin with.

According to the same paper quoted above, there is little to no archaeological or otherwise historical support to back up such a claim. For example, millions of dead rats from the same time period, which, there is curiously a lack of.  

Jordan Quinn Farkas
Jordan Quinn Farkas
Jordan is a full-time writer from his home in Southeast Europe. An avid outdoors-man and backpacker, he has gathered a plethora of tips and tricks for dealing with all sorts of pests.

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