Wyoming Department of Health officials said Monday, Aug. 25 they are investigating a case of bubonic plague in an out-of-state resident who recently visited Teton County and Yellowstone National Park. The individual traveled to multiple sites in the area with a group of Boy Scouts from July 26 to Aug. 3, said Dr. Tracy Murphy, state epidemiologist with the Wyoming Department of Health.

“The young adult traveled to Yellowstone National Park, Bridger-Teton National Forest and other sites within Teton County,” said Murphy. “He was involved in a combination of activities during his visit that included working on a service project, camping, sightseeing and participating in sports.”

Wyoming Department of Health staff will participate in an environmental investigation with other agencies this week to look for fleas and animal carcasses in areas where the individual visited. “At this time the exact location where the exposure to the disease occurred is not known and it is likely we will never determine that level of detail,” Murphy said.

Dr. Karl Musgrave, state public health veterinarian with the Wyoming Department of Health, said that while the risk for humans to contract plague is relatively low in Wyoming, the disease has been documented in animals in 22 of Wyoming’s 23 counties since records were kept.

This is the sixth human case of plague thought to be acquired in Wyoming since 1978. The most recent human case of plague in Wyoming was acquired in Goshen County in the fall of 2004. Other recorded cases involving residents include a 1978 Washakie County case, a 1982 Laramie County case, a 1992 Sheridan County case that resulted in death and a 2000 Washakie County case.

“It’s safe to assume that the risk for plague exists all around Wyoming,” Musgrave said. “And while the disease is rare in humans, it is important that people take precautions to keep exposure to the disease to a minimum.”

Ways to avoid the plague include:
• Avoiding unnecessary contact with rodents and their nests and burrows.
• Avoiding unnecessary contact with sick or dead animals, especially rodents and rabbits, and wearing protective gloves when handling sick or dead animals.
• Having ill pets, such as cats and dogs, examined by a veterinarian.
• Avoiding areas where a large number of unexplained rodent deaths have been observed.
• Keeping pets away from rodent nests and burrows by keeping them leashed.
• Treating pets with flea preventatives (see your local veterinarian for more information).

Murphy said that the typical sign of the most common form of human plague is a swollen and very tender lymph gland, accompanied by pain. The swollen gland is called a “bubo” (hence the term “bubonic plague”). Bubonic plague should be suspected when a person develops a swollen gland, fever, chills, headache, and extreme exhaustion and has a history of possible exposure to infected rodents, rabbits, or fleas. Murphy advised anyone experiencing these symptoms to see their health care provider.