The Hidden Danger in Pacific Northwest Waters: Sister’s Story and the Risk of Salmon Poisoning in Dogs

The Pacific Northwest is beloved for its lush trails and scenic rivers — the perfect setting for a weekend hike or a lazy afternoon by the water with your dog. But hidden beneath the beauty of our waterways lies a serious threat to dogs that many pet owners have never heard of: salmon poisoning disease.

This potentially fatal condition is found almost exclusively in the Pacific Northwest. It's caused by a bacterium known as Neorickettsia helminthoeca, which infects certain salmon and trout through a small fluke (a type of flatworm). When dogs eat raw or undercooked fish carrying this infected fluke, even just the guts or discarded carcass, they can become gravely ill within days.

That’s what happened to Sister, a sweet and adventurous pup from Portland.

After a fun weekend hiking near a local river where someone had been fishing, Sister likely got into discarded fish remains. A few days later, her family noticed something was wrong: she wasn’t eating, she was having nonstop diarrhea, and she seemed increasingly lethargic. Concerned, they rushed her to DoveLewis.

“Sister was very sick when she arrived,” said Dr. Sarah Tauber, a veterinarian at DoveLewis. “If a pet has salmon poisoning and goes without treatment, it’s often fatal.”

Fortunately, thanks to her family’s quick action and the expert medical care she received, Sister began antibiotics and supportive treatment immediately. She stayed at DoveLewis for several days while the team monitored her vitals, worked to manage her symptoms, and ensured her body responded to treatment. Slowly but surely, Sister began to recover, and she’s now safely back home.

What Pet Owners Need to Know About Salmon Poisoning:

Where it occurs: This disease is unique to the Pacific Northwest due to the specific parasites found in local salmonid fish.

How dogs get it: Raw or undercooked fish—especially salmon and trout—can be infected with a parasitic fluke. This fluke carries the harmful bacteria, which causes salmon poisoning when dogs eat contaminated fish, guts, or carcasses.

Symptoms: Vomiting, diarrhea, loss of appetite, fever, lethargy, and enlarged lymph nodes. Symptoms typically occur 5 to 7 days after exposure.

Why it's serious: Without treatment, salmon poisoning can often be fatal.

How to prevent it: Always supervise your dog closely near rivers, streams, and docks to prevent them from eating raw fish, fish carcasses, fish guts, or Pacific salamanders. Secure trash cans and properly dispose of fish remains to keep dogs from accessing these dangerous items.

Sister’s story shows just how rapidly salmon poisoning can progress—and why immediate action is critical if you suspect your dog has been exposed. If your pet has eaten raw fish near rivers or fishing spots, don’t wait to seek veterinary care. Early treatment can make all the difference in helping your dog recover safely.