California Resident Tests Positive for Plague After Camping at Lake Tahoe

First Human Case in Five Years Reported in El Dorado County

PLACERVILLE, CA - Health officials in El Dorado County confirmed Tuesday that a South Lake Tahoe resident tested positive for plague. This is the county’s first human case since 2020. The person likely got the disease from a flea bite while camping in South Lake Tahoe.

The patient is currently recovering at home under medical supervision. Officials from the El Dorado County Public Health Division shared the news. They were informed by the California Department of Public Health.

Disease Details and Transmission

Plague is caused by the bacterium Yersinia pestis. It mainly spreads when infected fleas bite. These fleas often feed on wild rodents, like squirrels and chipmunks. The disease can also spread by coming into contact with infected animals. Pets may bring fleas that carry the plague into our homes.

““Plague is naturally present in many parts of California, including higher elevation areas of El Dorado County,” said Kyle Fliflet, El Dorado County’s Acting Director of Public Health. ““It’s crucial for people to protect themselves and their pets outdoors. This is especially important when walking, hiking, or camping in places where wild rodents may be.”

Symptoms and Treatment

Symptoms of plague usually show up within two weeks of exposure. They can include fever, nausea, weakness, and swollen lymph nodes. The disease can be serious. However, if found early, it can be treated well with common antibiotics.

The Centers for Disease Control and Prevention states that the U.S. sees an average of seven human plague cases each year. These cases mainly occur in rural parts of western states. More than 80% of U.S. plague cases are of the bubonic form.

Local Context and Precautions

The California Department of Public Health checks rodent populations for plague activity. This year, they found four positive rodent infections in the Tahoe Basin. From 2021 to 2024, 45 ground squirrels and chipmunks in the Lake Tahoe Basin tested positive for the plague bacterium.

The last human plague case in El Dorado County was in 2020. It is thought to have spread in the South Lake Tahoe area. Earlier, two cases from California came up in 2015. These were tied to exposure at Yosemite National Park. All previous patients received treatment and made full recoveries.

Health officials recommend several precautions for outdoor enthusiasts:

  • Avoid contact with wild rodents and their burrows
  • Keep pets on leashes and away from rodent habitats
  • Use insect repellent containing DEET on socks and clothing
  • Wear long pants tucked into boots when hiking or camping
  • Never feed or touch wild rodents

Recent Regional Cases

This California case follows other recent plague incidents across the western United States. In July 2025, a person in Arizona died from pneumonic plague. This type is a rare respiratory form of the disease. Earlier this month, a cat in Colorado tested positive for bubonic plague and died.

The plague, also called the “Black Death,” hit Europe hard during the Middle Ages. Today, it’s a rare but ongoing health issue in the American West. Today’s infections can be treated with antibiotics if caught early. This is a sharp contrast to the medieval pandemic, which claimed millions of lives.