Canine Infectious Respiratory Disease in Oregon

In August, the Oregon Department of Agriculture (ODA) received anecdotal reports of an atypical canine infectious respiratory disease (CIRDC) circulating in the Willamette Valley. Since then, ODA has received over 100 case reports from Oregon veterinarians and has provided this update:

ODA is actively working with reporting veterinarians and specialists at OSU’s Carlson College of Veterinary Medicine (CCVM), the Oregon Veterinary Diagnostic Laboratory (OVDL), and the USDA’s National Veterinary Services Laboratory (USDA-NVSL) to find the causative agent behind these cases.

What is Currently Known

Based on the epidemiology of the cases reported at this point (case report "heat map" shown at right), the cases appear to share a viral etiology, but common respiratory diagnostic testing has been largely negative. A handful of cases do test positive for M. cynos, but that agent is not believed to be the underlying causative agent.

The cases reported to ODA appear to primarily fall within three general clinical syndromes:

• Chronic mild-moderate tracheobronchitis with a prolonged duration (6-8 weeks or longer) that is minimally or not responsive to antibiotics. 
• Chronic pneumonia that is minimally or not responsive to antibiotics.
• Acute pneumonia that rapidly becomes severe and often leads to poor outcomes in as little as 24-36 hours.

Next Steps

ODA is working with pathologists and virologists at the OVDL, as well as the USDA-NVSL to implement a diagnostic testing plan in these cases. In most cases tested to date, it appears that the period of shedding may already be passed by the time cases are seen by the reporting veterinarians. To address this limitation, ODA has engaged with several emergency veterinary practices to begin widespread sampling of potential respiratory cases, which will be paired with PCR testing using generic primers, virus isolation, and rapid whole genome sequencing in hopes of diagnosing an etiologic agent.

ODA is also working with an Animal Rescue Entity in the Salem area which had several cases within their rescue population to collect samples for serology. OVDL will be testing these samples using broad serologic tests to hopefully narrow down the pool of potential etiologic agents.

Recommendations for New CIRDC Cases

While ODA is still working to find the underlying cause of these atypical CIRDC cases, they request that any new suspected atypical Canine Infectious Respiratory Disease cases be reported to the ODA Disease Reporting Hotline at 503-986-4711. Until more is known about the causative agent, ODA recommends that cases initially be handled as normal, with diagnostic testing to rule out common causes of CIRDC, and treatment as necessary to address common bacterial agents when warranted by clinical/laboratory findings.

ODA is currently focusing initial diagnostic efforts (beyond targeted diagnostic projects mentioned above) on cases of acute pneumonia in which animals die or are euthanized. If you have a case that meets these criteria, please contact ODA immediately (503-986-4711) to make arrangements for necropsy and diagnostic testing at OVDL.

Should Dog Owners Be Worried?

We suggest caution rather than worry. Periodic outbreaks of Canine Infectious Respiratory Disease Complex (CIRDC) can occur in a dog population. At least nine different bacteria and viruses have been linked as causes of CIRDC, which is transmitted by respiratory droplets. Infection with more than one bacterial or viral agent is common. Symptoms include coughing, sneezing, nasal and/or eye discharge, and lethargy. If your dog shows these symptoms, please check with your veterinarian.

CIRDC Backgrounder

Periodic outbreaks of Canine Infectious Respiratory Disease Complex (CIRDC) can occur in a dog population and some cases can be serious. Transmitted by respiratory droplets, both viruses and bacteria can cause CIRDC. 

CIRDC cases more commonly occur in animals housed in settings such as shelters, boarding, or training facilities rather than in animals housed in private homes, especially those with limited access to other dogs.

Veterinarians treat cases according to the dog's symptoms and severity of symptoms. Treatment may include antibiotics. Most dogs, especially those vaccinated against respiratory illness, experience a mild illness.

Symptoms of CIRDC include coughing, sneezing, nasal and/or eye discharge, and lethargy. If your dog shows these symptoms, please check with your veterinarian.

Dog owners can protect their pets from respiratory illness by:

• Reducing contact with large numbers of unknown dogs. Just like with other respiratory pathogens, the more contacts your dog has, the greater the risk of encountering a dog that’s infectious. 
• Reducing contact with sick dogs. This can be harder to determine but if a dog looks sick (coughing, runny nose, runny eyes), keep your dog away from it. 
• Keep sick dogs at home and seek veterinary care. 
• Avoid communal water bowls shared by multiple dogs. 
• Ask your veterinarian for advice on which vaccinations your dog should have.
• If it's sick, consider having your dog tested with a PCR test to help determine the causative agent (viral/bacterial), if possible.

We will update this information as events warrant.