Health officials have confirmed that a California resident recently contracted the plague while camping in the South Lake Tahoe area. It’s believed the patient was bitten by an infected flea during their stay.
This marks the first confirmed human case of plague in El Dorado County since 2020. In 2015, two people tested positive after a visit to Yosemite National Park.
Human cases of plague are extremely rare, but there is always potential for infection. From 2021 through 2024, 41 rodents in El Dorado County tested positive for yersinia pestis — the bacteria that causes the plague. So far in 2025, four additional rodents have tested positive in the Tahoe Basin.
“Plague is naturally present in many parts of California, including higher elevation areas of El Dorado County," acting public health director Kyle Fliflet told NBC News. "It's important that individuals take precautions for themselves and their pets when outdoors, especially while walking, hiking and or camping in areas where wild rodents are present."
Those precautions include avoiding contact with squirrels, chipmunks, and other wild rodents, especially if they’re dead or injured. People should also wear long pants and bug repellant to prevent flea bites.
Thanks to medical advancements, the plague is no longer the lethal disease it once was. When diagnosed early, it can be successfully treated with antibiotics. Symptoms to look out for include fever, nausea, weakness and swollen lymph nodes. Symptom onset occurs within two weeks of exposure.