The Modern Resurgence of the Plague: What We Need to Know Today

Although the plague, historically known as the Black Death, is often associated with medieval Europe, it has not been entirely eradicated and can still appear in the modern world. Recently, a resident of South Lake Tahoe contracted the disease after being bitten by an infected flea while camping. This case highlights that while rare, the plague remains a potential health risk even in the 21st century.

Most famously, the plague killed about 25 million Europeans during the 14th century, wiping out roughly half of the continent's population. Today, experts like Professor John Swartzberg of UC Berkeley emphasize that the disease, caused by the bacterium Yersinia pestis, is a specific pathogen with a long history of causing devastating outbreaks.

The plague is primarily found in small animals and rodents, with humans typically infected through flea bites or contact with infected animals. There are three main types: bubonic, which involves swollen lymph nodes; septicemic, where the infection spreads throughout the body; and pneumonic, affecting the lungs. While medical advancements have made the disease more treatable, complete eradication remains elusive.

Historically, the disease was introduced to the U.S. via rat-infested ships from Asia, first appearing in San Francisco. The last rat-related case in California occurred in the 1920s, but sporadic human cases continue, often linked to outdoor activities in areas where infected wild rodents dwell, such as in California's rural, mountainous, and forested regions.

In California, the highest risks are associated with outdoor recreation in wilderness areas like the Angeles National Forest and San Gabriel Mountains. Pets can also become infected if they come into contact with infected fleas, posing additional risks to humans.

Despite no longer being a major public health threat, the plague persists due to the difficulty of eradicating infections within animal populations and their vectors. Currently, there are no FDA-approved vaccines for the plague, but early treatment with antibiotics can be highly effective. However, untreated infections can quickly become fatal.

Overall, while the plague is not a widespread threat today, the possibility of occurrence underscores the importance of awareness, preventative measures, and prompt medical treatment if symptoms appear. Experts agree that with timely intervention, the disease is manageable and poses little danger to the general population.