The bubonic plague has returned. Should I be worried? | News explained

Between 1346 and 1353, the bubonic plague caused the so-called Black Death, which killed as many as 50 million people in Europe. So are the recently discovered cases a cause for concern?

First, what is bubonic plague?

The cause of plague is plague bacteriumzoonotic bacteria, that is, bacteria that can spread between animals and humans. and the plague bacterium Usually found in small animals and their fleas.

Yersinia pestis in the foregut of a flea vector observed under an electron microscope. (National Institutes of Health)

According to the World Health Organization (WHO), humans can become infected in one of three ways. “bitten by an infected vector flea'', “unprotected contact with infectious body fluids or contaminants'' (such as being bitten by an infected rat), and “inhalation of droplets/fine particles from a patient with pneumonic plague.''

What are the symptoms of the disease?

Symptoms of plague appear in a variety of ways. Bubonic plague refers specifically to when the bacteria invades the lymph nodes. The disease can cause fever, headache, weakness, and painful or swollen lymph nodes, and is usually caused by an infected flea bite, according to the Centers for Disease Control and Prevention (CDC).

Septicemic plague occurs when bacteria enters the bloodstream. It often follows untreated bubonic plague and causes more severe symptoms. These include abdominal pain, shock, bleeding into the skin, and blackening of the appendages (most often fingers, toes, or nose). According to the CDC, this form is caused by flea bites or handling infected animals.

Pneumonic plague is the most dangerous and is “almost always fatal” if untreated, according to the WHO. As the name suggests, this occurs when bacteria invade the lungs, adding rapidly progressing pneumonia to the list of symptoms. According to the CDC, it is the only plague that spreads from person to person by inhaling infectious droplets, and it is also the most contagious plague.

What were the effects of the Black Death?

The Black Death was the deadliest disease outbreak in history, from 1918 to the 1920 influenza pandemic. Given the greatly reduced population levels in the 14th century, the Black Death remained the deadliest epidemic in history, killing up to half of Europe's population by some estimates.

Most of all, it left a lasting impact on those who survived. A study published in the journal Nature in 2022 found that certain genetic mutations increase the odds of survival by about 40 percent. This 40 percent “was the strongest selective fitness effect ever estimated in humans,” said Luis Barreiro, a professor at the University of Chicago. BBC.

Unfortunately, this mutation has since disappeared, but it is directly associated with the incidence of certain autoimmune diseases. This means that what happened 700 years ago may be impacting our health today.

The Black Death has passed Lasting social, economic and cultural impact Even in Europe and beyond.Historian James Belich, in his 2022 book A World Created by Plague: The Black Death and the Rise of Europe It argues that Europe's global dominance can be traced directly to medieval pandemics. While this may be an oversimplification, it nevertheless provides an interesting insight into the story of the Great Divergence that continues to shape the world today.

So should we be worried about another Black Death outbreak?

No, doctors do not expect the disease to spread from Oregon or cause human deaths.

Epidemics of bubonic plague were a thing of the past by the 1930s. According to the CDC, there are currently 2,000 cases of plague reported each year around the world, with most occurring in Madagascar, the Democratic Republic of the Congo, and Peru. The mortality rate is approximately 11%.

This is thanks to modern antibiotics, which can significantly combat the dangers posed by bacteria. and the plague bacterium, as well as improved hygiene and understanding of disease. According to the CDC, all forms of plague are treatable with common antibiotics, and early treatment greatly improves the chances of survival.

nevertheless and the plague bacterium Since the Black Death can still occur almost anywhere and can be deadly to individuals, it is nearly impossible for a larger pandemic to mirror the Black Death.