A person has tested positive for plague after possibly being bitten by an infected flea while camping in South Lake Tahoe, according to public health officials.
El Dorado County’s public health division announced the positive plague case on Tuesday and stated that the individual is currently under the care of a medical professional while recovering at home.
“Plague is naturally present in many parts of California, including higher elevation areas of El Dorado County,” Kyle Fliflet, El Dorado County’s acting director of public health, said in a news release. “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.”
No other information about the person or their condition was released but health officials said they are investigating the situation.
Plague is caused by the bacterium Yersinia pestis, and plague bacteria are most often transmitted by the bites of fleas that have acquired them from infected squirrels, chipmunks and other wild rodents, according to El Dorado County’s public health division.
They say dogs and cats may also bring plague-infected fleas into people’s homes and warn that people can get the disease when they are bitten by infected fleas. Plague can be prevented by avoiding contact with wild rodents and keeping pets away from rodent burrows.
Health officials say symptoms of plague usually show up within two weeks of exposure to an infected animal or flea and include fever, nausea, weakness and swollen lymph nodes. Plague can be effectively treated with antibiotics if detected early.
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The bubonic plague is the most common form of the bacterial infection, which spreads naturally among rodents like prairie dogs and rats.
There are two other forms: septicemic plague, which spreads through the whole body, and pneumonic plague, which infects the lungs. Pneumonic plague is the most deadly and easiest to spread.
Plague is rare in humans, with an average of about seven cases reported annually in the U.S., most of them in the western states, according to federal health officials.
Before the current case, the most recently reported case of human plague in El Dorado County was in 2020, and the person was likely exposed in the South Lake Tahoe area. Two people were also reported to have plague in 2015 after being exposed to infected rodents or fleas in Yosemite National Park. Both individuals were treated and recovered.
In July, a resident of northern Arizona died from pneumonic plague. The death in Coconino County was the first recorded death from pneumonic plague since 2007, local officials said. Further details, including the identity of the victim, were not released.
Most cases happen in rural areas of northern New Mexico, northern Arizona, southern Colorado, California, southern Oregon and far western Nevada, according to the Centers for Disease Control and Prevention.
Worldwide, plague is found the most in the Democratic Republic of the Congo, Madagascar and Peru, according to the World Health Organization.
The WHO also reported that 3,248 human cases of plague were reported worldwide from 2010 to 2015. This included 584 deaths.
There have been no known cases of human plague in Canada since 1939, though the Public Health Agency of Canada continues to monitor for it.
El Dorado County’s public health division shared tips to prevent plague, which include not feeding squirrels, chipmunks or other wild rodents; never touching sick, injured or dead rodents; and not allowing your pets to play with or pick up sick, injured or dead rodents.
Officials warned the public not to camp, sleep or rest near animal burrows or areas where dead rodents are observed and to look for posted warning signs.
It’s also suggested that people wear long pants tucked into boot tops and spray insect repellent containing DEET on socks and pant cuffs to reduce exposure to fleas.
— With files from The Associated Press
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