Spawning salmon pose potential dog illness

Dog owners advised to keep dogs on leash at local waterways

A potentially deadly risk to dogs is on the rise as salmon end their journey to spawn up local waterways. The disease specific to canines is known as “salmon poisoning disease” and can occur if a dog consumes an infected raw salmon or other species of anadromous fish.

“Salmon poisoning disease is a serious and often fatal disease of dogs, coyotes and foxes of the Pacific Northwest,” Emily Fecso, veterinary assistant at Olympic Veterinary Clinic, said.

Although the disease is more closely associated with slow moving rivers and streams, local veterinary clinics “absolutely get cases around here and it’s something to be aware of,” Fecso said.

The disease, unique to areas stretching from northern California to British Columbia, derives from a microorganism called Neorickettsia helminthoeca, Fecso said. The microorganism is the disease agent that lives in parasitic flatworms known as flukes.

“The parasitic flukes have three different hosts including snails, fish and lastly dogs,” she said. “When a dog eats a fish with an infected fluke, the fluke will release the microorganism, making the dog very sick.”

Fecso’s two canine companions recently contracted what veterinarians believe was salmon poisoning disease earlier this year following a trip to Freshwater Bay. Shortly following her dogs’ recovery, the experience prompted Fecso to further research the disease and share information about it via the clinic’s blog, she said.

Amplifying the need to know, state and tribal officials estimated a record number of pink salmon to return to the Dungeness River in late summer and fall, equating to between 1.1 and 1.3 million.

After spawning and as carcasses of a possible million or more salmon line the river’s edge, the smell of fish can be tempting for dogs.

“Living in the Pacific Northwest, precautions always must be taken to prevent your dog from being exposed to salmon poisoning disease,” Fecso said. “If you’re planning on hiking along a river or going to a beach with possible dead salmon, please keep your dog on a leash.”

Beyond keeping a watchful eye, Fecso also noted, if planning to fish, it’s best to thoroughly cook all fish before allowing your dog to eat any and keep them away from the area where the salmon were cleaned and prepped.

Symptoms may appear within six days of a dog eating an infected fish and can include vomiting, lack of appetite, fever, diarrhea, weakness, swollen lymph nodes and dehydration, according to officials with Washington State University College of Veterinary Medicine. If untreated, salmon poisoning disease typically results in death within 14 days.

Despite the serious consequences of the disease, it’s treatable if caught early.

“A physical examination and fecal sample can help your veterinarian diagnose salmon poisoning disease and rule out other diseases with similar symptoms,” Fecso said.

Following diagnosis, treatment may include antibiotics, antiemetics, anti-diarrheal and intravenous fluids, she said.

The disease doesn’t pose a risk to humans, but for the next couple of months Fecso doesn’t recommend walking dogs along the Dungeness River.

For more information on salmon poisoning disease, visit www.olympicveterinaryclinic.com.

Reach Alana Linderoth at alinderoth@sequimgazette.com.