‘Mystery’ disease may be sickening dogs in California. Here’s how to protect your pet

An unusual, potentially deadly disease is spreading among dogs in the United States, but a California veterinary expert advises people to not sound the alarm, yet.

Disease experts are studying a potentially fatal illness in dogs, which has been reported both officially and anecdotally across the country, including Oregon, California and Washington, NBC’s “Today Show” reported in November.

“We’re seeing a definite uptick in respiratory diseases,” said Erik Olstad, a general practitioner and assistant clinical professor with the UC Davis William R. Pritchard Veterinary Medical Teaching Hospital. “In rare cases, it can turn serious or fatal.”

According to a Nov. 17 news release from the American Veterinary Medical Association, the Oregon Department of Agriculture has seen more than 200 case reports from veterinarians since mid-August.

The disease is still a “mystery,” the department said, as specialists are trying to find the cause of the illness.

Olstad said the disease is “atypical” compared to other common respiratory illnesses in dogs.

“The tough thing is, we’re testing these dogs with this kind of mysterious disease, and they’re not showing up positive for a lot of the common things that we would see that would cause cough like canine influenza,” he said. “So we’re just a little confused on what’s going on.”

Since experts don’t know what the pathogen causing the illness is, he said, they can’t confirm its transmission, too.

Olstad added that he doesn’t want people “thinking that there’s this wild illness wiping out millions of dogs. That’s not the case.”

What are symptoms of the disease affecting dogs?

The AMVA said dogs sickened by the mystery illness experience chronic mild to moderate inflammation of the trachea, which lasts up to eight weeks or longer. Other symptoms include chronic or acute pneumonia that becomes severe rapidly within 24 to 36 hours.

Medications are not working well to treat these symptoms, the AMVA said.

Olstad said other signs of this illness are difficulty breathing, coughing, nasal discharge, low energy and lack of appetite.

If your dog is showing signs of sickness, Olstad recommends that you speak to a veterinarian right away and avoid taking your pet out in public places.

“There are things that we can look at, like if your dog has a really high fever with this cough, that can be tough for you to detect at home,” he said.

Is the illness in California?

Is the illness spreading in California? It’s a tough question, Olstad said.

“Since we don’t know what this illness is,” he said, “I can’t confirm if a dog comes into my office with a cough that that’s the illness because dogs have a bunch of illnesses that cause cough, nasal discharge, difficulty breathing ...”

The Los Angeles County Department of Public Health’s Veterinary Public Health Program is looking into reports of dogs with “sudden respiratory illness of unknown origin,” officials announced Tuesday.

The dogs tested negative for common viruses and bacteria seen in canines with similar symptoms of cough, sneezing and lethargy.

“Owners are being contacted to determine where the dogs may have become infected,” the department said. “We are communicating with federal and state entities to ensure coordinated efforts as we learn more from our ongoing investigations.”

The San Diego Humane Society reported on Nov. 15 that four dogs have died in its clinic due to illnesses, but the society attributed those deaths to a respiratory disease called streptococcus equi subspecies zooepidemicus, or, strep zoo.

The shelter also reported infections involving a bacteria called mycoplasma.

While the Pacific Northwest is seeing an uptick among dogs in coughs that turn fatal, Olstad said, UC Davis’ vet clinic hasn’t experienced that.

“We haven’t really seen a ton of that in my section of the hospital,” Olstad said. “I’ve treated a bunch of dogs with coughs but I haven’t had to deal with any fatal repercussions.”

How is mystery sickness spread?

While it’s still being studied, Olstad said the illness is infectious and may spread much like human respiratory diseases.

This means it can spread through contact with sick animals from respiratory droplets, such as when a dog sneezes or when a dog drinks out of an infected water bowl.

How to prevent your dog from contracting respiratory illness

Experts are advising dog owners to decrease contact with other dogs, according to the Los Angeles Times.

Olstad said you don’t need to lock your furry friend in a room, but just avoid other sick animals and large groups of unknown dogs.

If you have another dog in your household that’s healthy, they can play together, but you should steer clear of dog parks and shows.

“It would be just fine if you still went out on your walks and you hung out with known dogs that are well-vaccinated and are healthy,” he said.

Olstad also said that people should make sure their dogs are completely vaccinated for para-influenza, canine influenza and bordetella, which is the kennel cough vaccine.

Andrea Cantu-Schomus, communications director with the Oregon Department of Agriculture, advised pet owners to talk to their vets for further advice.

“Because of the broad spectrum of potential respiratory diseases, there is no one-size-fits-all recommendation, and working with a veterinarian is the best way to ensure that owners have accurate information that is appropriate for their situation,” she said in the AMVA release.

This story was originally published November 22, 2023 at 8:30 AM with the headline "‘Mystery’ disease may be sickening dogs in California. Here’s how to protect your pet."