First Human Case of Plague in California in Five Years Strikes, Officials Say

After the Black Death in the 14th century, the bacterium "Yersinia pestis" mutated to become less deadly

By Jonny Lupsha, Wondrium Staff Writer

The plague has infected a California resident for the first time in five years, ABC News reported. Although the news is surprising, plague is treatable if detected early and widespread outbreaks rarely occur. Plague in the modern world is a shadow of its former self.

Plague blood test, resulting positive
Plague in modern times is much less virulent than in ancient times and is spread by infected fleas carried by rodents. Photo By Jarun Ontakrai / Shutterstock

According to ABC News, a rare medical event struck the state of California last week when a resident tested positive for plague—the first human in five years to do so.

“El Dorado County health officials were notified by the California Department of Public Health (CDPH) that a resident in South Lake Tahoe had tested positive for the plague and that it is thought that person, who is an avid walker, may have been bitten by an infected flea while walking their dog along the Truckee River Corridor,” the article said.

“The patient who tested positive for the plague is currently under the care of medical professionals and is recovering at their home.”

It may sound frightening, but due to advancements in science and medicine, the plague is a much smaller threat than it was in the past—even though it should still be treated with caution.

Plague in the 21st Century

“While plague can now be treated with antibiotics and is not widespread, it still exists,” said Dr. Dorsey Armstrong, Associate Professor of English and Medieval Literature at Purdue University. “And because it’s relatively uncommon, 2015 saw more deaths from plague than in 2014 and 2013 combined—for the simple reason that no one recognized what it was at the time. Granted, these deaths are still in the single digits, but it’s a reminder that this ancient enemy is still around.”

Since the 1980s, our concerns about dangerous illness have mostly focused on diseases like HIV/AIDS, Ebola, SARS, and MERS. Since November 2019, the new coronavirus has taken the spotlight as well. However, Dr. Armstrong said it’s not a bad idea for the scientific community to remain vigilant about the plague, scientifically known as Yersinia pestis.

The Black Death may still be around in part because, after its initial virulent outbreak, it mutated to become less deadly,” she said. “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.”

The Indomitable Human Spirit

However, even in times of great strife, people often rise to the occasion and combat adversity.

“The best and most encouraging lesson we can take away from a study of the Black Death is that human beings are resilient and can surprise you,” Dr. Armstrong said.

“While many accounts describe bodies lying in the streets and people fleeing friends and family to escape from the plague, which I think is a perfectly understandable human reaction given what was happening, these accounts also tell of ordinary people stepping up and going to extraordinary extremes to offer help and comfort, [like] parish priests who performed their duties humbly and sincerely and most of whom died because of it.”

Dr. Armstrong mentioned Saint Roch as one of those parish priests. She also credited the leaders in government who calmed their citizens while working to stop the plague through policy and members of the public “who buried children and husbands and wives and then, somehow, managed to keep going.”

A few errant cases of plague around the world don’t register as a pandemic or a cause for alarm. However, should case numbers rise, humanity has shown its resilience in medicine and in spirit before.

Dr. Armstrong is Associate Professor of English and Medieval Literature at Purdue University

Dr. Dorsey Armstrong contributed to this article. Dr. Armstrong is Associate Professor of English and Medieval Literature at Purdue University, where she has taught since 2002. The holder of an AB in English and Creative Writing from Stanford University and a PhD in Medieval Literature from Duke University, she also taught at Centenary College of Louisiana and at California State University, Long Beach.