Source of Norovirus in Puget Sound: Shellfish Grower Says "Too Much Poop" in Puget Sound Making Shellfish Unsafe

Whose poop is to blame?

South Sound Mariculture Oyster

Declared unsafe.*

Time to consider oysters grown on the East Coast for now?

Tacoma's The News Tribune writes about a Puget Sound shellfish grower saying there is too much "poop" in Puget Sound causing oysters grown there to be unsafe to eat. John Hansen, owner of South Sound Mariculture, has spoken before both the City of Shelton's City Commission and Mason County Commissioners. There, he expressed his belief that the source of norovirus which caused his and other shellfish farms in south Puget Sound's Hammersley Inlet to be closed, is the City's waste water treatment plant. That plant discharges directly into Oakland Bay and Hammersley Inlet. The City of Shelton strongly disagrees with Mr. Hansen's claim.

Humans aren't the only mammals

increasing in population around Puget Sound.

Whose poop is it that the oysters are filtering and in turn making humans sick?

Through the shellfish growers, focus is being placed on septic systems and, in the case of Mr. Hansen, the City of Shelton's waste water treatment plant as being the source of norovirus his and other's oysters are contaminated with. However, norovirus is not limited to humans, and humans are not the only mammal increasing in population in or around Puget Sound, a point noted by Tristan Baurick in 2016, who wrote, "...the harbor porpoise is making a startling comeback after a nearly complete disappearance from local waters more than 40 years ago." More to the point, a January 2017 paper published by the Center for Disease Control notes:

"...the fact that noroviruses infecting marine mammals closely related to human noroviruses have been found infecting harbor porpoises and contaminating oysters raises the question of whether HPNV could infect humans through contamination of oysters or other shellfish."

He did it! No, it was her! Not me, it was him! 

Porpoise are not the only mammals

making their presence known.

Norovirus in northwest shellfish was not limited to Hammersley Inlet, but covered a wide geographic area.

This year, the number of illnesses contracted through the consumption of northwest oysters was not limited to Hammersley Inlet and numbered in the multiple hundreds. This was considered to be a widespread outbreak, ranging from Willapa Bay in the south to the waters of British Columbia*. After months of trying, the source, despite Mr. Hansen's belief, is still not known. In fact, given the wide geographic area and multiple shellfish operations implicated, it seems more likely the disease is being spread through means other than the City of Shelton's waste water treatment plant or on site septic systems. Whether the wide ranging pods of porpoises, sea lions, or even Orca are the source is not known, but cannot be discounted.

*The article in The Globe and Mail on oyster illnesses from British Columbia also notes in a short clip at the end the Humpback Whale population increasing from 6,000 to 21,000 since 1993. Shown is a drone capturing "whale snot" being exhaled to test for pathogens.

Send in the Orca to clean up the mess.

But don't they "poop" too? 

Half baked ideas are as bad as half cooked oysters contaminated with norovirus.

Before agencies chase ghosts attempting to make waters clean enough for shellfish growers to make (quoting Mr. Hansen) "$10,000 per month" from his small tideland parcel, they should first confirm just exactly what the source of the problem is. If they are wrong, and illnesses continue, the east coast shellfish growers will be able to take market share which will be very difficult to re-acquire. 

Is a drainfield this close to 

a shellfish farm a good idea

if you're worried about norovirus?

Does that green grass

in August

indicate anything?

Edited May 10: The Department of Health has declared portions of Hammersley Inlet open to commercial harvesting again. (see below - red/brown closed)

City of Shelton 

Portions of Oakland Bay and Hammersley Inlet

Edited May 11: The Department of Health has declared the area at the end of SE Mell Road open to commercial harvesting. Portions of the north shore and west end where the waste water treatment plant discharges into Oakland Bay and Hammersley Inlet remain closed.