A South Lake Tahoe resident has tested positive for the plague — yes, the same pest-transmitted disease estimated to have killed 25 million Europeans in the Middle Ages.
It is believed that the person contracted the rare and dangerous disease after being bitten by an infected flea while camping in the South Lake Tahoe area, according to El Dorado County health officials. The patient is currently under the care of a medical professional and recovering at home, health officials said.
“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, in a statement. “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.”
Plague is a very serious disease but can be treated with easily available antibiotics, according to the U.S. Centers for Disease Control and Prevention. The sooner a patient is diagnosed and receives treatment, the greater their chances of making a full recovery, according to the CDC.
The disease is caused by the bacterium Yersinia pestis and is most commonly spread to humans by bites from infected fleas, according to El Dorado County health officials. The disease can also be spread by infected-rodent bites or by exposure to infected dogs and cats.
The disease is extremely uncommon and infects on average seven people in the U.S. per year, according to the CDC. Nevertheless, it must be taken seriously due to the high potential for death if left untreated.
The last plague case reported in El Dorado County was in 2020 and was also believed to be transmitted in the South Lake Tahoe area, health officials said. Two California plague cases were reported in 2015, likely caused by bites from an infected flea or rodent in Yosemite National Park. All three patients received treatment and made a full recovery, health officials said.
There were 45 ground squirrels or chipmunks recorded with evidence of exposure to plague bacterium in the Lake Tahoe Basin from 2021 to the present, according to the California Department of Public Health, which routinely monitors rodent populations for plague activity across the state.
El Dorado County health officials urged residents and visitors to take steps to avoid exposure to rodents or ticks when exploring the wilderness around Lake Tahoe. Measures include wearing long pants tucked into boots, using a bug repellent with DEET, never feeding or touching rodents, refraining from camping near animal burrows or dead rodents, and leaving dogs at home when possible.
More than 80% of plague cases in the U.S. have been in the bubonic form, where patients will develop swollen, painful lymph nodes called buboes, according to the CDC. This form of the disease typically results from an infected-flea bite, and symptoms such as buboes, fever, headache, chills and weakness develop within two to eight days, according to the CDC.
In July, an Arizona resident died of the pneumonic form of the plague, which can develop when bacteria spreads to the lungs of a patient with untreated bubonic plague. This is the most serious form of the plague and can have an incubation period of just one day. It’s also the only form of the plague that can spread from human to human.
During the Middle Ages, infected rats were to blame for the black death in Europe in the 14th century. The last urban rat-infected plague outbreak in America took place in Los Angeles in 1924 and 1925, according to the CDC.
