Mystery Respiratory Illness in Dogs

Given the recent concerns of respiratory illness in dogs that is being reported throughout the country, we wanted to provide some insight to the pet owners in our community.

What do we know so far?

In August 2023, the Oregon Department of Agriculture (ODA) first received reports of an atypical canine infectious respiratory illness being seen in dogs in Portland. To date, ODA has received over 200 reports of atypical canine infectious respiratory disease from Oregon veterinarians. ODA is actively working with reporting veterinarians and specialist in their state to find the causative agent behind these cases.

Based on the epidemiology of the cases reported to date, ODA says the cases appear to share a viral etiology, but common respiratory diagnostic testing has been largely negative, and the cause remains unknown. A handful of cases have tested positive for a bacteria called Mycoplasma cynosbut that is not believed to be the underlying causative agent (and suspected to be more of a co-infection).

Other to Oregon, dogs with similar symptoms have also been reported in Colorado, Massachusetts, Rhode Island, and New Hampshire. There are other states (such as Florida, California, Indian, Illinois, Washington, Idaho, Georgia) where dogs with similar symptoms are reported, but it’s unclear if it’s the same disease or other respiratory illness such as CIRDC (canine infectious respiratory disease complex or "kennel cough").

What are the symptoms of this illness and how is it spread?

Common symptoms from this illness include:

• Coughing
• Sneezing
• Labored breathing
• Nose or eye discharge
• Lethargy
• Decreased appetite

Dogs affected with symptoms either experience chronic signs with a prolonged duration (i.e 6-8 weeks) that is minimally or non-responsive to antibiotics before improvement. However, some dogs also developed rapid, progressive symptoms that can be fatal, in as little as 24-36 hours.

The illness appears to spread through direct contact or through water droplets from sneezing and coughing.

Should pet owners be worried?

We are suggesting to exercise caution rather than worry. The number of cases reported to ODA represents a very small percentage of Oregon's dog population. Although we are seeing respiratory cases elsewhere in the country, we do not have reason to believe that these cases are related to an unknown disease vs periodic outbreak of CIRDC.

Although there's concerns of a new disease, there are some experts in infectious diseases that believe this is more likely the usual suspects doing their usual thing (possibly at higher rates in some areas).

In other words, we don’t know if the current cases reflect:

• A multistate outbreak caused by some new bacterium/virus.
• A multistate outbreak caused by our usual suspects, for some reason.
• Unconnected sporadic local outbreaks caused by usual suspects that cause CIRDC.
• A slight increase in known diseases such as CIRDC.
• Our normal disease activity with an outbreak of media attention.

Although there's some thought that we may not truly be dealing with a new illness, we also do not want to completely rule out the possibility of new infection. Part of the challenge we face as veterinarians is that there’s no effective surveillance system. Some regions have no official report systems and other regions have only voluntary reporting systems. PCR testing can be expensive and there's typically little or no funding available for routine testing for dogs with respiratory illness.

What can be done to protect my dog from this illness?

Dog owners can help protect their pets from respiratory illnesses in general 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 them.
• 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. Common vaccinations include canine influenza, Bordetella and parainfluenza.
• If your dog is sick, consider having your dog tested with a PCR test to help determine the causative agent (viral/bacterial), if possible.

What is CIRDC (canine infectious respiratory disease complex or "kennel cough"?

Canine infectious respiratory disease complex (CIRDC), more familiarly known as "kennel cough," is a highly contagious illness affecting the respiratory tract in dogs. All breeds and ages are susceptible. As the name "kennel cough" suggests, dogs at particular risk are those exposed to settings where multiple dogs are typically gathered or housed, such as kennels, shelters, and daycare facilities, rather than in animals housed in private homes, especially those with limited access to other dogs.

Several different types of bacteria and viruses can contribute to CIRDC, and dogs can be affected by two or more of these organisms at the same time. Vaccines are available for many of the viruses and bacteria that causes CIRDC, however vaccines doesn’t completely prevent infections but does decrease the severity of symptoms associated with infections.

Although viral organisms are more common to cause CIRDC, antibiotics are sometimes used to treated CIRDC because of primary bacterial infections (Bordetlla or mycoplasma) or for secondary bacterial infections. Another bacteria called Streptococcus zooepidemicus, is also a rare cause of CIRDC, but can cause rapidly fatal disease. These infections typically occur as outbreaks in shelters or high stress settings.

Links to additional information: