Salmon Poisoning Disease - Parasite Organism Can Harm Dogs Who Eat Raw Fish

When visiting bodies of water with dogs, be on the alert for dead fish or entrails that may carry a parasite organism harmful to dogs if ingested. Local veterinary clinics in Portland are seeing cases of Salmon Poisoning Disease on the rise. Keep dogs on leashes and leads around water, don’t let them eat raw fish, and properly dispose of fish remains to prevent infections.

What is salmon poisoning disease?

Salmon poisoning disease is a potentially fatal condition seen in dogs after they eat certain types of raw fish, like salmon and other anadromous fish (fish that swim upstream to breed), that are infected with a parasite called Nanophyetus salmincola.

The parasite is relatively harmless except when it is infected with a rickettsial organism called Neorickettsia helminthoeca. It’s this microorganism that causes salmon poisoning. 

Salmon poisoning occurs most commonly west of the Cascade Mountain range.

Does Salmon Poisoning Disease Affect People?

Humans can get infected only if they eat raw fish, or if they do not practice good sanitation in preparing fish. When humans are infected, they experience mostly mild diarrhea. Safe food handling practices can prevent infection.

What are the signs of salmon poisoning disease in dogs?

Clinical signs generally appear within six days of a dog eating an infected fish. Common symptoms include:

  • Vomiting
  • Lack of appetite
  • Fever
  • Diarrhea
  • Weakness
  • Swollen lymph nodes 
  • Dehydration

Salmon poisoning is treatable if it’s caught in time. If untreated, death usually occurs within two weeks of eating the infected fish. Ninety percent of dogs showing symptoms die without treatment.

How is salmon poisoning disease diagnosed?

Salmon poisoning can be diagnosed with a fecal sample or a needle sample of a swollen lymph node.

How is salmon poisoning disease treated?

Given the severity of the condition, treatment is relatively simple. An antibiotic will be prescribed by your veterinarian to kill the rickettsial organisms that cause the illness, and a wormer will be given to eliminate the parasite. Most dogs show dramatic improvement within two days. 

If the dog is dehydrated, intravenous fluids are administered.

What should I do if I suspect my dog has salmon poisoning disease?

If you suspect your animal is sick, contact your veterinarian.


The best treatment is prevention.

  • Control what your dog eats while on fishing trips.
  • Leash your dog at the beach or river so that you can monitor its activities.
  • Wrap garbage, especially fish entrails, and dispose in well-secured cans.
  • Don't feed raw fish to your dog. Cook fish thoroughly or deep-freeze it for a minimum of 2 weeks to destroy the parasite before feeding it to your dog.
Dog at beach