Update: Canine respiratory disease outbreak

Update: Canine respiratory disease outbreak

This page was last updated on 11/30/23.

Over the past several months, CVMA has received many phone calls and emails from veterinarians seeking guidance on the canine respiratory disease outbreak in Colorado and across the nation.

CVMA, CSU, and state veterinary officials are aware of the University of New Hampshire’s recent pathogen findings in the outbreak; as mentioned in the UNH press release, they are unsure of the significance of this finding at this time, or if that is the causative agent in this widespread outbreak. Colorado State University has continued to test samples and have found several positive cases on routine diagnostic tests, including parainfluenza, canine coronavirus, and pneumovirus. Based on the testing done in Colorado, we have yet to identify a single causative agent to tie these cases together.

It is unknown if the uptick of cases seen in some states is viral or bacterial. Viral cases do not need antibiotics; for now, if bacterial disease is suspected, veterinarians are advised to follow the ISCAID Respiratory Treatment guidelines. If the case is a bacterium, CSU and state officials hope to know best antibiotic choices in the coming weeks.

Click here to see additional information regarding this outbreak from the Colorado Department of Agriculture.


Veterinarians are reporting they are seeing double the number of what is typically seen during a canine infectious respiratory disease outbreak. The cases are presenting with prolonged coughing which can last weeks to months with minimal response to treatment. In some cases, the dogs have progressed to contracting pneumonia and require hospitalization.  In rare cases, the canine patients progress quickly from pneumonia to death.

Some diagnostics have been done, but there has not been any conclusive testing to indicate what may be causing the increased prevalence of this respiratory disease. This may be due to lack of testing or testing too late in the course of disease. Ideal testing for suspected viral infection would be within the first 72 hours of onset of clinical signs and prior to initiating therapy.

CVMA has worked with partners from the Colorado Department of Agriculture (CDA), Colorado State University (CSU) Veterinary Teaching Hospital (VTH) and Veterinary Diagnostic Laboratory (VDL), the Colorado Department of Public Health and Environment (CDPHE), and the United States Department of Agriculture (USDA) to better understand the current situation and formulate a response. The Colorado Department of Agriculture has set up a website with additional information.

Tips for owners

Practices can share the following tips with pet owners heading into the holidays to help them protect their pets:

  • Reduce your pet’s exposure by limiting commingling with other dogs outside the home (including holiday gatherings, dog parks, boarding, grooming, veterinary clinics, and play groups)
  • Ensure dogs are up-to-date on vaccinations, including canine influenza, bordetella, and parainfluenza
  • Consult with your veterinarian if your dog becomes ill; early diagnostics may help in getting an accurate diagnosis and treatment

Media coverage

CVMA will share additional guidance for veterinarians as it becomes available.