Salmon Poisoning

Image by ArtTower on Pixabay.
Image by ArtTower on Pixabay.

What is salmon poisoning disease?

Salmon poisoning disease is a potentially fatal condition seen in only 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.

What are the signs of salmon poisoning disease?

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 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 or the WSU Veterinary Teaching Hospital at 509-335-0711.

This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.