Prairie dogs carry three diseases that can spread to humans: plague, tularemia, and mpox (monkeypox). Plague is the most significant and the most common reason prairie dog colonies suddenly die off. All three infections are rare in people, but they’re serious enough that avoiding contact with wild prairie dogs, especially sick or dead ones, is a standard public health recommendation across the western United States.
Plague
The bacterium Yersinia pestis cycles naturally among wild rodents, and prairie dogs are one of its most visible hosts. When plague sweeps through a prairie dog colony, it can kill nearly every animal, sometimes wiping out entire towns of thousands in weeks. The die-off itself becomes the danger point for humans: as infected prairie dogs die, their fleas lose their blood source and actively seek new hosts, including people, pets, and other animals nearby.
You can also catch plague by handling the tissue or body fluids of an infected animal directly. This is a risk for hunters, trappers, and anyone who picks up a dead prairie dog out of curiosity. The disease still occurs in the U.S. every year, concentrated in the rural West. New Mexico reported its first human plague case of 2025 in a 43-year-old man from Valencia County; the previous case in the state was in 2024. Colorado, Texas, Arizona, and other western states see cases periodically as well.
In humans, plague takes three forms depending on how the bacteria enter the body. The most common form from flea bites causes painfully swollen lymph nodes (called buboes), high fever, and chills. Without antibiotics, the infection can spread to the lungs or bloodstream and become life-threatening. With prompt treatment, most people recover fully.
Tularemia
Tularemia is caused by Francisella tularensis, a bacterium that prairie dogs can harbor along with rabbits, muskrats, and other rodents. A notable outbreak occurred in 2002 when commercially distributed pet prairie dogs transmitted tularemia to their owners. The incubation period is typically 2 to 6 days but can stretch to 14.
Symptoms come on suddenly: high fever, chills, headache, muscle aches, and a general feeling of weakness. A dry cough and chest discomfort are common. If the bacteria entered through a cut or scrape on your skin, an ulcer usually develops at that spot along with swollen lymph nodes nearby. Tularemia is treatable with antibiotics, but the initial illness can be severe enough to require hospitalization.
Mpox (Monkeypox)
In 2003, the first mpox outbreak in the Western Hemisphere was traced directly to pet prairie dogs. The chain of infection started with a shipment of rodents imported from Ghana, including Gambian giant rats. An animal vendor in Illinois housed those African rodents near prairie dogs, which picked up the virus and passed it to their eventual owners. By the time the outbreak was contained, 87 human cases had been reported across six states: Wisconsin, Indiana, Illinois, Ohio, Kansas, and Missouri.
That outbreak led to a federal ban, still in effect, on importing African rodents and on the commercial sale and distribution of prairie dogs. The FDA and CDC imposed these restrictions specifically to prevent mpox from establishing itself in North American rodent populations. Prairie dogs themselves aren’t a natural reservoir for the virus, but the 2003 event proved they can pick it up from infected animals and transmit it efficiently to people through close contact.
How to Tell a Prairie Dog Is Sick
A healthy prairie dog is alert, active, and social. An infected animal looks visibly wrong: fever, lack of energy, loss of appetite, difficulty breathing, and dehydration are all signs of plague infection. Swollen lymph nodes and an enlarged spleen occur but aren’t visible from a distance. The most reliable warning sign for a colony isn’t a single sick animal but a sudden absence of activity. If a normally busy prairie dog town goes quiet, plague may be moving through it, and the area should be avoided entirely.
Where the Risk Is Highest
Plague is endemic in prairie dog populations across the western U.S., with Colorado, Texas, New Mexico, Arizona, and parts of South Dakota being well-documented hotspots. Black-tailed prairie dogs, the most widespread species, occupy grasslands from Montana to northern Mexico. Any active colony in these regions could potentially harbor plague, though outbreaks are sporadic and localized. Wildlife agencies in several states monitor colonies and sometimes close parks or trails when die-offs are detected.
To protect wild colonies, the U.S. Geological Survey and university partners developed an oral plague vaccine delivered in peanut butter-flavored bait pellets scattered near burrow entrances. In a three-year field trial across 12 locations, about 70 percent of wild prairie dogs consumed the vaccine baits. This approach helps preserve colonies that are critical habitat for endangered species like the black-footed ferret, while also reducing the reservoir of plague bacteria that can eventually reach humans.
Protecting Yourself Near Prairie Dog Habitat
The core rule is simple: don’t touch prairie dogs, alive or dead, and stay away from their burrows during or after a die-off. Fleas are the primary transmission route, and they’re most aggressive when their rodent hosts have recently died.
If you’re hiking, camping, or working outdoors in prairie dog country, use EPA-registered insect repellent containing DEET, picaridin, or oil of lemon eucalyptus. Wear long pants, long sleeves, and tall socks to keep fleas and ticks off your skin. Remove any attached ticks promptly, and don’t drink untreated surface water, which can carry tularemia bacteria.
If you hunt, trap, or handle any wild rodents or rabbits, wear gloves and cook game meat thoroughly. When mowing or landscaping in areas where prairie dogs live, check the ground for carcasses beforehand and avoid running over dead animals, which can aerosolize bacteria. A mask may reduce the risk of inhaling tularemia bacteria during these activities, though this hasn’t been formally studied.
Pets are also at risk. Dogs and cats that roam near prairie dog colonies can pick up infected fleas and bring them home, or cats can catch plague directly by eating infected rodents. Keeping pets on flea prevention and away from prairie dog burrows is the most practical step you can take to break that chain of transmission.