SALT LAKE CITY — State health officials are investigating a case of bubonic plague, which killed an elderly man in Utah earlier this month.

It is the first case of human plague since 2009 and the first death caused by the plague in 35 years, though there have been a dozen cases reported in seven states since April this year, according to the Utah Department of Health.

JoDee Baker, an epidemiologist for the health department, said the disease is found on wild rodents throughout rural parts of Utah every year and it is transmitted by fleas. Human transmission, however, is rare, she said.

Residents in rural Utah and people who travel there for camping and other activities should be aware of the potential for plague and protect themselves, the health department warns.

In addition to rodents, culprits include prairie dogs, ferrets, squirrels and rabbits.

While Utah's case remains under investigation, officials believe the man contracted the disease either from a flea, or contact with a dead animal. It is not believed that the man traveled anywhere plague is common.

Three cases, two in Georgia and one in California, have been linked to exposure at Yosemite National Park in central-eastern California. Officials there have tried to control the rodent population there, but any wild area carries some risk.

The risk of plague for urban populations is "extremely minimal," Baker said.

Symptoms of plague include fever, headache, chills and general weakness a week after possible exposure and then painful, swollen lymph nodes, Baker said. While plague is serious, it can be treated with antibiotics if it is caught early enough.

The earlier a person seeks medical care and receives treatment that is appropriate for plague, the better chances are for a full recovery, according to the health department.

Baker said the Utah man who died of plague did not seek immediate treatment.

To best avoid exposure to plague-ridden rodents, the health department suggests reducing rodent habitats around homes and work areas, including rock piles and cluttered firewood, as well as removing possible rodent food supplies, such as pet and wild animal feed. Officials suggest wearing gloves when skinning wild animals, and using repellent containing DEET or permethrin when camping, hiking or working outdoors.

Free-roaming animals and pets should be treated regularly with flea control products and should not be permitted to sleep on a person's bed. Wild game should be cooked to a temperature of 165 degrees Fahrenheit and should not be ingested raw.

Epidemics of the plague occurred throughout Europe during the Middle Ages and was likely brought to America in the early 1900s by "rat-infested steamships" that sailed from infected areas of Asia, according to the U.S. Centers for Disease Control and Prevention. The latest epidemic in the states ended in 1925, but pockets of infection continue to be reported in regions of the western United States.

"It's a rare disease in general," Baker said. "It most commonly lives in areas where people just don't go very often and even then, it happens by chance."

The health department did not release additional information about the Utah man who died, Baker said, "out of respect for his family."

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