Something Smells Fishy: The Dangers of Salmon Poisoning 

Summer weather is on its way and many in the Pacific Northwest are dusting off their fishing gear while planning their next adventure. As you think about bringing your furry best friend with you to explore the great outdoors or adding some fish to your dog’s diet, we’d like to share a cautionary tale of two pups in critical condition.

Rogue and Brick arrived last week at the Humane Society for Tacoma & Pierce County. Even at first glance, our veterinary team immediately knew something was wrong with the dogs. They were showing symptoms similar to deadly parvovirus – diarrhea, vomiting, and extreme weakness, to name a few.

But the rapid parvo tests came back negative. Twice. So why were they so sick?

Brick receiving veterinary care.

Finally, on day three, we received the in-depth test results we had been waiting for. Rogue and Brick were suffering from salmon poisoning disease.

“The name is a bit misleading,” says Dr. Katherine Spaulding, associate shelter veterinarian at the Humane Society for Tacoma & Pierce County. “Dogs do get sick from eating raw or undercooked salmon and other fish, but it’s really a parasite inside the fish that causes the damage, called a fluke.”

Flukes, or parasitic flatworms, are generally harmless to dogs unless it’s infected by harmful bacteria called neorickettsia helminthoeca. Once a dog has eaten raw salmon, trout, or other fish, the infected flukes implant themselves into the dog’s intestines, releasing the bacteria into the bloodstream.

This chain of events is what leads to a critical situation. As the bacteria spread, the dog becomes deathly ill.

A dog with salmon poisoning disease may experience loss of appetite, vomiting, diarrhea, weight loss, weakness, fever, enlarged lymph nodes, and an increase in discharge from the eyes or nose.

Veterinary staff caring for Rogue.

“The mortality rate of this disease is often really high,” says Dr. Spaulding. “If left untreated, dogs usually succumb to the disease within seven to ten days.”

Salmon poisoning disease is about 90% fatal to dogs if left untreated. With such a high fatality rate, early diagnosis and treatment are essential.

Your local veterinarian can diagnose the disease by examining a dog’s fecal sample for fluke eggs, performing blood work, and examining a sample of the enlarged lymph nodes.

Once a dog is diagnosed, antibiotics help control the spread of the bacterial infection, and prescribed medication will kill the flukes. For dogs with severe symptoms like Rogue and Brick, hospitalization may be required for intravenous fluids and medications to avoid severe dehydration.

Rogue and Brick have received round-the-clock care with antibiotics, anti-parasitic medications, fluids, and constant monitoring. Although the dogs are slowly showing signs that they are feeling better, their healing journeys have just begun.

As you’re enjoying the great outdoors, here are some additional tips to keep your pets safe and healthy: 

• Make sure any fish provided is cooked thoroughly and is safe for dog consumption.   
• Ensure your dog is current on flea and tick prevention. 
• Have your dog wear a secure collar or harness with identification. Better yet, get your pet microchipped and make sure your information is linked! 
• For hot weather, provide fresh water and take breaks to avoid your pup overheating. 
• Have pet first aid essentials on hand such as bandages and antibiotic ointment for those unexpected emergencies.