Last week a sick dog from outside Larimer County was euthanized at the Colorado State University Veterinary Teaching Hospital (CSU VTH) after being hospitalized for four days. This dog tested positive for Yersinia pestis, the bacteria that cause plague. The type of plague this dog had was pneumonic plague, which is a lung infection.  The dog may have become infected by sniffing a dead prairie dog a day or two before becoming ill.

There is no plague risk to the general public, clients of the hospital, or to staff and students on the CSU campus other than those that cared for the dog or handled tissue specimens at the hospital. CSU VTH has identified students and staff who worked closely with this animal and has reached out to those individuals.  For those with a high-risk direct exposure, preventative treatment has been recommended. The need for preventive treatment depends on the length and proximity of exposure to the dog. Persons with less exposure may be asked to monitor their temperature for fever for a week. Those who were exposed to the dog pose NO danger to anyone else as long as they do not become sick themselves.

Should a contact develop any symptoms consistent with plague, the person would receive more intense treatment with intravenous antibiotics. CSU has provided students and staff who were exposed with guidance from the Colorado Department of Public Health and Environment, and asked them to see their health care provider to determine their best treatment option.

Those who were not exposed directly to this animal are not at risk. Pneumonic plague can be contracted from breathing in nearby droplets from an infected coughing animal or human. This transmission usually requires direct and close contact with the ill person or animal.

Plague is not uncommon in our rodent populations in Colorado, and the potential of infections in our domestic animals exists throughout the state. This dog was the 7th domestic pet found to have plague in Colorado this year. It is rare for humans to develop plague, but it can happen. Plague is treatable if caught early.                                                                    


  • Avoid contact with all sick and dead rodents and rabbits. Look for the presence of blow flies or dead animal smell as evidence of animal die-offs. Prairie dog colonies that suddenly are not active may also be due to plague activity in the area. Report such die-offs to Larimer County Department of Health and Environment at 970-498-6775.
  • While hiking, treat pants, socks, shoe tops, arms and legs with insect repellents.
  • Keep your pets from roaming and hunting, and talk to your veterinarian about using an appropriate flea control product.
  • Sick pets should be examined promptly by a veterinarian.
  • If you hunt or trap rabbits or carnivorous wild animals, wear gloves and a respiratory mask while skinning or handling these animals. Fresh pelts may be treated with flea powder.
  • Bites from wild carnivores and from cats and dogs have caused human plague. Such animals may be infected, carry the bacteria in their mouths or may transport infective fleas. If you are bitten, follow-up with your health care provider.
  • DO NOT feed or entice any rodent or rabbit species into your yard, back porch, or patio.
  • Eliminate rodent habitat, such as piles of lumber, broken cement, trash and weeds around your home, outbuildings and cabins.
  • When outdoors, minimize exposure in rodent-infested areas. Do not catch, play with, or attempt to hand feed wild rodents.

For more information on plague, visit http://www.larimer.org/plague

For more tips on insect repellents for people, visit http://bit.ly/2kYZab4

Published on: 
Wednesday, December 13, 2017 - 5:10pm
Contact Details: 

Katie O'Donnell

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