SW Idaho cat infected in problem area known for previous plague cases

This map shows the potential plague affected area in southwest Idaho, which largely includes Elmore and Ada counties.
This map shows the potential plague affected area in southwest Idaho, which largely includes Elmore and Ada counties. Courtesy of Idaho Fish and Game

One month after the first human case of the plague since 1992 was reported in Elmore County, laboratory tests indicate a cat in Elmore County was also infected with the plague.

The cat had recent contact with a rodent, which may have been a ground squirrel, also known as a whistle pig, before becoming ill, according to the Idaho Department of Health and Welfare.

The cat was treated promptly by a veterinarian and is recovering.

No additional pets or people are ill, according to Health and Welfare.

While Idaho wildlife officials have not detected any ground squirrel die-offs in the state so far this year, the infected cat lives within an area of southern Idaho identified in previous years as a plague-affected area.

The plague circulates every year in Idaho in fleas, which can affect ground squirrels, voles and mice.

“It is important to take precautions to avoid contact with ground squirrels and their fleas,” said Dr. Leslie Tengelsen, Idaho State Public Health veterinarian. “Make sure your pets have proper flea control and keep them away from ground squirrel habitat, if possible.”

Plague is transmitted through the bite of infected fleas and can cause serious illness in people and pets if not treated promptly. Tree squirrels in Idaho are not known to carry plague.

Health officials recommend the following:

  • Do not feed rodents in picnic or campground areas and never handle sick or dead rodents. Keep your pets from roaming and hunting ground squirrels or other rodents in affected desert areas.
  • Talk to your veterinarian about using the appropriate flea control product on pets to protect them and reduce the chance that they bring fleas into the home. Note: not all products are safe for cats and dogs so read the labels carefully.
  • Reduce rodent habitat. Clean up areas near your home where rodents can live, such as woodpiles. Put hay, wood, and compost piles as far as possible from your home.
  • Have your sick pets examined promptly by a veterinarian, especially if they may have had contact with sick or dead rodents in the desert areas south and east of Boise and Mountain Home.
  • See your doctor if you have any unexplained illness involving a sudden and severe fever after being in a plague-impacted area.
  • Don’t leave pet food and water where rodents or other wild animals can access them.

Symptoms of plague in humans include sudden onset of fever, chills, headache, and weakness. In most cases there is a painful swelling of the lymph node in the groin, armpit, or neck.

Plague symptoms in cats and dogs include fever, lethargy, and loss of appetite. There may be a swelling in the lymph node under the jaw. With prompt diagnosis and appropriate antibiotic treatment, the chance of recovery is greatly increased.

Physicians and veterinarians who suspect plague should promptly report it to their local public health district, day or night.

History of the plague in southwest Idaho

In late May 2018, an Elmore County child was diagnosed with plague — the first human case in Idaho since 1992. The child was treated at a hospital and is recovering at home. It remains unknown whether the child was exposed to plague in Idaho or during a recent trip to Oregon.

In 2015 and 2016, plague was identified in ground squirrels. During this time, ground squirrel die-offs were reported in the desert south of the Boise Airport and around Mountain Home.

In 2015, one dog tested presumptive-positive. In 2016, six cats tested positive, most from the greater Mountain Home area. For more information on plague (including a searchable map), or to report a rodent die-off of five or more animals, visit https://idfg.idaho.gov/plague.