Ground squirrels found dead in the desert in Ada and Elmore counties have initially tested positive for plague, prompting a warning from public health and wildlife officials for the second year in a row.
Authorities are still confirming the diagnosis. But people out and about in the desert southeast of Boise and Kuna should take precautions for both themselves and their pets, including not feeding rodents and not handling sick or dead rodents. This year, the area in question runs as far north as Interstate 84 in Boise, including the Boise Airport.
A bacterial disease, plague can be spread by the bites of fleas or by direct contact with infected animals. The plague is believed to have reached Idaho in about the 1930s and has likely been in the ground squirrel population for decades.
“Just like last year, our investigation began in May after hearing reports from people finding dead ground squirrels in the desert southeast of Boise,” State Wildlife Veterinarian Dr. Mark Drew said. “We hope to have confirmation of these results soon and will keep the public up to date as we learn more.”
Idaho Fish and Game asks for the public’s help to track and report plague incidents. The agency wants to hear from you about reports of more than five dead ground squirrels, yellow-bellied marmots, voles, cottontail rabbits or jackrabbits. (But please don’t report incidents of just one dead animal, authorities ask — they’re not as useful.) If you find such a group of dead animals, don’t touch them; file a report at this link.
Since 1940, only five human cases of plague have been reported in Idaho. The last two cases reported in Idaho occurred in 1991 and 1992, and both patients fully recovered, the Idaho Department of Health and Welfare reports.
In 2015, one dog that had contact with ground squirrels in the plague area contracted the disease, but recovered. Plague was also found in voles near Caldwell and near the Duck Valley Indian Reservation farther south.
Plague is generally transmitted through bites of infected fleas. It may also be transmitted by direct contact with infected animals, including rodents, rabbits and pets. Common rodents that can become infected include mice, rats, voles, chipmunks and ground squirrels, officials said. Tree squirrels in Idaho are not known to carry plague.
Plague activity can increase in the spring and summer months when rodents are more active. People can be exposed to plague when pets have contact with rodents or fleas outdoors, or bring infected rodents or fleas back into the home. People can also become infected by caring for a sick pet without proper precautions.
People can greatly reduce their risk of becoming infected with plague by taking simple precautions, including avoiding contact with wild rodents, their fleas and rodent carcasses. They should not feed rodents in parks, picnic or campground areas and never handle sick or dead rodents.
Health officials also suggest:
• See your doctor about any unexplained illness involving a sudden and severe fever.
• Keep your pets from roaming and hunting voles or other rodents. Sick pets should be examined promptly by a veterinarian, especially if they may have had contact with sick or dead rodents.
• Talk to your veterinarian about using an appropriate flea control product on pets. Not all products are safe for cats, dogs or children.
• Don’t leave pet food and water where rodents or other wild animals can access them.
• Clean up areas near your home where rodents can live, such as woodpiles and lots with tall grasses and weeds.
• Put hay, wood and compost piles as far as possible from your home.
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 areas. Plague symptoms in cats and dogs are 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 fatality rate in people and pets can be greatly reduced. Physicians who suspect plague are asked to promptly report it to their local public health district.