It began with what my friend, Bill, assumed was kennel cough. His beagle buddy, Chester, seemed lethargic and wasn’t eating. So, Bill made an appointment with his vet. The next day, Bill canceled the appointment. Chester had died overnight. Bill was devastated. Sadly, this incident is not unique. A mysterious and sometimes fatal respiratory illness is targeting dogs across the U.S., and scientists are scrambling to figure it out.
Frustrating mystery illness in dogs
Researchers are frustrated. This infection was first noticed back in August. Since that time, it’s been difficult to determine the cause or an effective treatment for this disease. Dogs generally present with signs of an upper respiratory disease but do not always test positive for some of the more familiar illnesses. Also, a frustration is that the mystery illness is generally resistant to standard treatments. Meanwhile, dog owners aren’t sure what to do.
Symptoms
Here is a list of symptoms that suggest your dog may be infected. Vets recommend that if your pup displays any of these symptoms, you need to seek immediate attention for your pup pal.
- Sneezing and/or coughing. Infected canines may experience inflammation of the bronchial airways or trachea. Symptoms can emerge suddenly and sometimes last for weeks. While a kennel cough is a “dry” cough, this infection often features a “wet” cough.
- Lethargy. Your dog may sleep more than usual or display a loss of her normal vitality.
- Fever. According to our local vet, a dog’s normal temperature runs from 101–102.5 Fahrenheit. If your dog’s temp registers above this, you should see your vet.
- Difficult and/or rapid breathing. Dogs affected by this mysterious respiratory illness may also be observed wheezing or snuffling.
- Nasal or eye discharge. Infected pups may have this discharge along with the other symptoms.
- Loss of appetite and weight loss. Along with lethargy, if your canine companion eats markedly less or refuses to eat, talk to your vet.
- Dehydration. Similar to appetite suppression, if your pup shows little to no interest in drinking water, it may warrant a mention to your vet.
Secondary infections
Experts advise pet owners not to panic. This illness isn’t generally fatal. However, it can quickly lead to secondary infections like pneumonia and other serious respiratory conditions that are non-responsive to antibiotics. Vets also warn that acute pneumonia can suddenly turn severe—as quickly as within 24–36 hours.
Where is this mystery illness in dogs happening?
To date, 14 different states in the U.S. have reported this mysterious, sometimes fatal, illness targeting dogs. These states are California, Colorado, Florida, Georgia, Idaho, Illinois, Indiana, Maryland, Massachusetts, New Hampshire, Oregon, Rhode Island, Vermont, and Washington.
There is no centralized reporting system in place for an outbreak like this. So, tracking this Canine Infectious Respiratory Disease Complex or CIRDC is even more difficult. Researchers think that isolating and identifying this emerging virulent pathogen may eventually lead to answers.
Treatments
Many dogs with mild symptoms can be treated successfully at home when provided with fluids, lots of rest, and medication for the cough. Other dogs experience a quick progression of the disease that will require more aggressive treatments and sometimes even hospitalization.
Thus far, no therapy has been able to treat this illness with absolute certainty. However, some dogs who experience a serious illness return to health after:
- Treatment of antibiotics for secondary infections
- Oxygen therapy
- Nebulizer treatment to get medication into the dog’s lungs
- Providing hydration and nutrition via an IV
Prevention
Is there a way to prevent my dog from contracting this mystery illness? That’s what dog owners want to know. Once again, here’s what veterinarians advise:
- Make sure your pup is up to date with all vaccinations—especially for kennel cough.
- Do not let your dog drink from communal water bowls.
- Avoid close contact with other dogs. This means dog parks, animal shelters, groomers, pet stores, boarding kennels, dog shows, and enclosed places with other animals (e.g., doggie daycare).
- If you’ve had contact with unfamiliar dogs, wash your hands thoroughly before touching your own dog.
- If your dog is sick, keep him well away from other dogs.
Most at risk
Some dogs are more at risk of developing a severe illness than others. Dogs with a higher risk are usually:
- Young pups (16 weeks or less) who have yet to complete all required vaccines
- Dogs with suppressed immune systems because of heart disease, cancer, chronic respiratory disease, or kidney disease.
Still stings
I shared this information with our friend, Bill. He said, “It makes sense now. Chester was fighting heart disease. With his weakened immune system, he just wasn’t strong enough to survive this. His death still stings, though. I miss him.”
Here’s a website that may help if you’ve recently lost your pup.


I am curious. Veterinary Clinic waiting areas are not mentioned as a possible source of contagion along with those listed. A prior call for any complaint may be a good idea. Thank you for this news.
I would caution any dog owner to avoid their vet clinic unless they call first. I’m sure vets are taking extra precautions to sanitize their waiting areas but do all you can to protect your pet.
We often do this. Especially with pregnant bitches and mom’s with litters. Good idea for older dogs also.
Great article about coping with pet loss. Another website offering helpful support tips and online virtual meetings is https://beyondthepawprint.com/
In addition, the book “Tails From Beyond the Paw Print” by Dr. Micky Golden Moore on coping with pet loss is a wonderful resource.
The illness affecting dogs sounds to me like a canine Covid. Of course I’m no vet or doctor.
Yikes!!!!! Thanks for the news, Gail! I’ll pass it along to our dog trainer (Weagle is in puppy training with her) and see what she says. Thank you so very much!