The Black Death: Is The Plague Still A Threat?

From a Lecture series taught by Dorsey Armstrong, Ph.D.

The Black Death seemed a particularly horrible kind of plague because it would periodically appear and disappear over the span of about three centuries. No one could know when an outbreak was really and truly over, and we can imagine that after 300 or so years of this, no one dared to get their hopes up that this outbreak might be the last.

image of woman with face mask for The Black Death plague article

The Third Pandemic, and Beyond

The Black Death struck the world in three separate pandemics—the Plague of Justinian, the Black Death, and the outbreak in India and China at the end of the 19th century. But did you know that the Third Pandemic has never been officially declared over? And did you know there was a 1994 plague epidemic in Surat, India, which eerily recalls many aspects of the Second Pandemic from the mid-14th century?

For starters, there’s the event that triggered the plague—an earthquake, just like so many of those medieval plague accounts described. In those instances, because earthquake was mentioned right after conjunction of planets and right before infected air/miasma, there’s a tendency to discount an earthquake as relevant to the outbreak of the Black Death.

What happened in 1994, however, is that an earthquake near the village of Mamla seems to have displaced large colonies of rats from their native territories. As they moved into areas with high concentrations of people, the plague made a jump to the human population. It wasn’t caught quickly because India, like many other countries, had stopped paying attention to or worrying about plague. And once the infection was established, it followed the movements of people—in this case, migrant workers who were heading into the city of Surat, which had a population of one-and-a-half million.

The other thing that most likely allowed plague to get a stronghold foothold in the city before anyone understood what was happening was because of the form the epidemic took: not bubonic, with its telltale swelling and petechiae on the skin; not septicemic, which can kill so quickly and which is harder to transmit from person to person. No, the form that swept through Surat was pneumonic, which in its earliest stages looks a whole lot like the flu. It’s only when a lot of people suddenly start coughing up blood that someone might figure out that this is not simple influenza.

Read more: The Black Death: Symptoms and Diagnosis of The Plague

Add to this the fact that the first infections raged through the slums of the city, where quarters were close, good health care nonexistent, and governmental oversight severely lacking, and you can see how the plague grew to a tipping point where it could not be effectively contained anymore. It’s estimated that 78 percent of confirmed cases of plague—not just suspected, but confirmed—were in the slums of Surat.

It Was Too Late To Help The Sick

A scanning electron micrograph depicting a mass of Yersinia pestis bacteria in the foregut of an infected flea
A scanning electron micrograph depicting a mass of Yersinia pestis bacteria in the foregut of an infected flea

What’s chilling is that the rest of the story continues to follow much of the template for plague reaction that we saw in the medieval world. Once health care officials did figure out what was going on and tried to react, they found they were woefully underprepared. There was a shortage of antibiotics. Medical professionals in the hardest hit areas abandoned their posts.

Shortly after the outbreak in Surat, plague was discovered on Madagascar. Alarmingly, one of the strains of Yersinia pestis found there is resistant to all known antibiotics used to treat plague. All of them. It turns out, Yersinia pestis is a clever little bacterium, and when it comes in contact with other bacteria, it borrows material from them and rewrites its own genetic code. This process is called lateral gene transfer, and scientists have figured out that Yersinia pestis has recently borrowed from E. coli and salmonella. The lesson here is a chilling one, and it’s one we would all do well to heed.

Read More: Europe on the Brink of the Black Death: The Plague Begins

Epidemic On The Move

And there’s always the possibility of bacterial mutation. In fact, the Black Death may still be around in part because, after its initial virulent outbreak, it mutated to become less deadly. After all, a pathogen that kills off most of the hosts it needs to survive is also threatening its own existence. While Yersinia pestis today is arguably less lethal than it was in the 14th century, another mutation and transformation is always possible, and that mutation could go the other direction.

Adding to this concern is the simple fact that the world is much more interconnected today than it was in 1348. If the plague spread so quickly via sea travel and the movement of Genoese merchant ships through the Mediterranean, imagine what an infected person on an international flight might do. Indeed, we don’t have to imagine it—we know. Both the SARS and MERS epidemics spread quite quickly via international flights.

In the end, the important lessons of the Black Death and other plagues are about the people and communities who survived these illnesses, even though the voices of those people are mostly lost to posterity. The losses were huge, and so many were buried in mass graves or dumped into rivers with nothing to mark their final resting places. But, by and large, civilization remained. It had changed, it was forced to adapt—but in our world today, which arose out of the medieval world, we are more like the people of the Middle Ages than we are different. This bodes well for the future of humanity, no matter what should come our way.

From the Lecture Series The Black Death: The World’s Most Devastating Plague
Taught by Professor Dorsey Armstrong, Ph.D.