What Dog Parents need to know about the Mysterious Canine Respiratory Illness – 

From a Veterinarian’s perspective, as of the first week of December 2023.

As most of you are aware, a mysterious dog respiratory illness has been spreading across the United States. This illness has caused symptoms in hundreds, perhaps thousands, of dogs across the country.

This mysterious respiratory illness has now been documented in 14 states, including Illinois. Since the holiday season is in full swing and that means more travels, I am concerned this disease will travel even faster in the coming months. As a dog mom myself, it is important that we help spread the word and educate ourselves as best as possible on what is emerging.  

Who does this mysterious respiratory illness affect? 

Currently, only dogs have been affected. The illness has not been reported in cats or other species. It also does not appear to be zoonotic, meaning dogs are not passing it to humans. 

What is the illness?  

Veterinary researchers across the country have been studying this illness for about a year now. Hundreds and possibly thousands of dogs have been infected; however, the good news so far is that only a small percentage of dogs have passed away from this illness. 

Typically, when a dog is showing signs of an upper respiratory infection, it could be viral, fungal, or bacterial. There are specialized tests that can be done to help determine the underlying cause, such as PCR and fungal testing.  The current PCR tests look at multiple viruses and bacteria. So far, this mysterious illness has not been detected on any available respiratory testing. It has yet to be determined if this is a virus, fungus, or a more resistant strain of bacteria affecting the respiratory tract of canines.

What are the clinical signs associated with this mysterious illness?

Coughing, sneezing, wheezing, and discharge from the eyes and/or nose are some of the first signs of concern. More concerning signs are when a dog also then begins to have a lack of appetite, starts acting depressed, and/or becomes dehydrated. The most concerning sign is when a dog starts having difficulty breathing. This can be a true emergency, and an ER facility should be sought out as soon as possible. 

Some dogs can develop acute pneumonia. Just like in humans, comorbidities are a concern.  This means dogs that have multiple disease processes present or are already immunocompromised will have a harder time if they catch this illness. Again, just a small percentage have passed away from this illness.  

So far, this illness is affecting all age groups, and the cough can persist for months. This cough lasts much longer than the typical cough caused by “Kennel Cough.” 


This illness is very contagious! 

Currently, the exact mode of transmission is unknown. Most respiratory diseases are spread through close contact with an infected individual. Just like it is respiratory season with us, that close-to-close contact where we could sneeze or cough on one another is most likely how this is spreading between dogs. We do not know at this time if it is spread through licking or sniffing areas where infected dogs have been. We also do not know how much fomites (objects touched by an infected dog) are contributing to the spread. For our dogs, fomites would be toys, leashes, carpet, bedding, etc. It is also unknown if some dogs may be asymptomatic carriers.

What we recommend: 

Make sure your dog is up to date on the available respiratory viruses/bacteria vaccines. For us in the Chicagoland area, that means keeping current on the:

  1. Distemper Combination vaccine (vaccinates against adenovirus and parainfluenza virus). 

  2. Bordetella bronchiseptica bacteria vaccine (we call this vaccine the “Kennel Cough” vaccine).

  3. Both strains of Influenza vaccines (H3N2 & H3N8). We vaccinate with the combination influenza vaccine that includes both strains in one.

Social distancing your dog from other unknown vaccinated dogs!  

This means keeping away from unvaccinated, unknown dogs – no visits to dog parks, no socializing with strange dogs on walks, and using caution with boarding facilities, grooming facilities, dog classes, and dog events. If you need to take your pet into an area with other dogs, choosing a place that requires dogs to be current on their respiratory vaccines is best.  

Current treatment options and what to do if your dog develops a cough: 

When in doubt a vet visit is always best! 

Dogs clinical for an upper respiratory disease will be closely monitored by our dedicated veterinary staff. Here at The Welcome Waggin’ we have the benefit of seeing dogs in the privacy of their own homes, which allows us the added ability to decontaminate between visits. We also have the capability to take chest x-rays in the home. Most dogs will not require hospitalization, but will need supportive care. Treatment will be aimed at preventing dehydration by administering subcutaneous fluids and by prescribing antibiotics if a secondary bacterial infection is suspected; unfortunately there is no expectorant cough medication for dogs. We also have a team of passionate certified veterinary technicians (CVTs) that will be checking in on you and your pet as we all work through this illness together. If we feel a patient is not improving, we work closely with and refer to local specialty and ER facilities if a pet is needing a more intensive treatment plan. 

As new developments emerge, researchers and top veterinary infectious disease specialists across the country are providing continuing education online lectures. 

We will continue to monitor this situation and provide updates as they become available.