Department of Health Issues Warning on Illness Contracted from Oysters

Reported infections from Vibrio bacteria in oysters are soaring

[Update 8/18: Food World News reported erroneously that Drakes Bay Oyster Company oysters had caused the California Department of Health to close their operation due to vibriosis traced to their oysters. Their mistake has caused a flurry of attorney calls, emails, retractions, and accusations from DBOC owner Kevin Lunny that it was part of a perceived conspiracy to "damage our business". Fervent supporters Jane Gyorgy and Sarah Rolph also responded with dismay. With the warm summer temperatures not yet over it may have been better for all to let a mistake be recognized as such.]

[Update 8/17: The Department of Health has closed Samish Bay, Reach Island, Hammersley Inlet, Totten Inlet, Oakland Bay and Pickering Passage growing areas to the commercial harvest of oysters due to reported illnesses traced to oysters harvested from those growing areas. Recreational information may be found on DOH website.]

 

The Department of Health has issued a warning to consumers telling them to stop eating raw oysters due to the risk of contracting vibriosis from them. August 13, The Seattle Times wrote:

Reported infections from Vibrio bacteria are soaring in King County.

In the warning issued August 13, the Washington Department of Health notes:

State health officials expect the number of illnesses to rise in the next few weeks due to projected warm temperatures and midday low tides.

Every summer the pattern repeats, in greater numbers each year
Vibriosis is caused by Vibrio parahaemolyticus which is a naturally occurring bacteria which increases dramatically every summer. Bacteria within oysters, natural filter feeders, increases further when day time low tides expose them to the sun. Every summer the pattern repeats with people becoming ill, followed by after the fact closures. The difference is each summer more people become ill.

Center for Disease Control

reported a 43% increase in

Vibriosis contracted in 2012

over 2006-2008

(CDC, April 18, 2013)

For each case reported an estimated 142 are unreported
Megan Kay epidemiologist at Public Health — Seattle and King County, estimates that for every reported case there are an additional 142 which go unreported. The Center for Disease Control also estimates the same number are unreported.

Increasing risk
In California, disease from Vibrio vulnificus (a more virulent strain of vibrio) was brought to zero by banning the import of untreated oysters from the Gulf States during the warm summer months. With the increasing use of genetically modified "triploid" oysters they become more palatable during the summer months (they are sterile so do not "spawn" and become milky). This in turn leads to increased numbers of people being put at risk, especially those whose immune systems are suppressed or who simply take antacids (acid helps to break down the bacteria). This on top of warming waters from climate change leads to increasing risk and increasing illness.

Economic hardships
To date the industry has resisted firmly what is the logical step, treating oysters to kill the bacteria before they enter the food stream, as California requires those from the Gulf States to be. While industry complains of economic impacts to their companies, there is also an economic cost to families, the health system, and companies impacted from people who contract vibriosis.

For now ...
Until meaningful actions are taken the best suggestion is found in The Seattle Times article published on August 14:  Don't eat raw oysters.

Ilnesses from Samish Bay Oysters Halts Harvesting

The Department of Health has closed Samish Bay to commercial harvesting of shellfish due to vibriosis contracted by people who consumed oysters harvested from the area. It will remain closed until October 1. Last year outbreaks of vibriosis and resulting closures of commercial harvesting areas, including Samish Bay, caused China to recall all oysters harvested from Washington state [read here].

Taylor Shellfish's processing plant in Samish Bay.

(from Google Earth, 8/25/11)

Unlike fecal coliform, Vibrio parahaemolyticus (Vp) is a naturally occurring bacteria in Puget Sound. Unlike fecal coliform, every summer Vp numbers increase in the water column. Oysters and other shellfish then filter Vp from the water. If the shellfish are undercooked or eaten raw, it may cause vibriosis. In addition to Samish Bay, Vp has already caused Oakland Bay, Totten Inlet, Dabob Bay, and areas in Hood Canal.

Whether the apparent increase in outbreaks and significant closures are the result of an increase in Vp, additional monitoring, the increase of triploid (genetically modified) oysters which are more "edible" during summer, or a combination is not known.

For a report from August 23 listing all areas closed and why, see the Olympic Penninsula Environmental News here. It does not include the most recent Samish Bay closure but does include areas closed for other reasons (e.g., biotoxins).

Department of Health contacts for various closures follow.  

Closure Explanations and Program Contacts: 

  BIOTOXIN - Biotoxin sample results exceed DOH closure standards

       Contact Frank Cox 360-236-3309 or Jerry Borchert 360-236-3328

  WWTP - A Wastewater Treatment Plant Malfunction

       Contact Mark Toy  360-236-3321

  HAZMAT - Hazardous Materials Substance Spill

       Contact Mark Toy  360-236-3321

  RAIN - The Conditionally Approved growing area is closed due to pollution associated with rainfall

       Contact Scott Berbells 360-236-3324

  MARINA - Seasonal Use Marina Closure

       Contact Mark Toy 360-236-3321

  FLOODING - Growing area is closed due to contamination from river flooding

       Contact Scott Berbells 360-236-3324

  EMERGENCY - Other public health emergency

       Contact Office Mainline 360-236-3330

  VIBRIO - A closure due to the naturally occurring pathogenic marine bacteria "Vibrio parahaemolyticus"

       Contact Richard Lillie 360-236-3313

  NO PSP SAMPLE / NO HARVEST - Geoduck tracts.  Must sample for PSP prior to harvest

       Contact Frank Cox 360-236-3309 or Jerry Borchert 360-236-3328

Hood Canal Oysters Recalled

An outbreak of vibriosis has initiated a recall of oysters harvested after August 16 from Hood Canal's Area 5 (just north of the southern "Great Bend"). Vibriosis, caused by the naturally occurring bacteria Vibrio parahaemolyticus (Vp) is an annual problem during the summer months for Washington's shellfish growers, moreso for those who become ill. Unlike most who contract vibriosis, reported cases are not getting better.

(from "Shellfish Safety", Department of Health)

(Note: The above numbers do not

include unreported cases, only those

confirmed by laboratory testing.)

Last year China banned the import of oysters from Washington State due to a similar outbreak and recall. Taylor Shellfish spokesman Bill Dewey responded: “This has wreaked havoc on our export business,” he said (Puget Sound Business Journal, 9/30/2011). Those who got ill were not interviewed for their response to what havoc, economic or otherwise, vibriosis caused in their lives.

In response to the FDA issuing a recall of the contaminated oysters last year, the shellfish industry sent a delegation of representatives, attorneys and lobbyists to Washington D.C. with this message for Congressman: "Despite seemingly adequate efforts by firms and SSCAs [State Shellfish Control Authorities], the FDA has unilaterally decided to elevate recalls and issue press releases which have unnecessarily alarmed consumers and had significant economic consequences on shellfish growers and distributors." (From the Pacific Shellfish Grower's Association's "FDA's Communications practices Hurth Shellfish Producers" handout dated February 2012.) It is unclear what "adequate efforts" industry lobbyists were referring to. What is clear is vibriosis is not under control.

As Governor Gregoire presses forward to expand the shellfish industry she should consider what she is leaving as her legacy. Scientists on her "Blue Ribbon Panel" have questioned whether the shellfish industry's expansion is something which should be promoted. Washington State's shellfish are causing increasing numbers of Vibriosis and other diseases. Warming temperatures can be expected to increase these numbers. She might consider listening to what her appointed scientists are saying. 


 
 

Vibrio Testing Closes Oakland Bay to Commercial Oyster Harvesting, Drakes Bay Oysters Recalled

The Department of Health has told shellfish farmers in Oakland Bay (Shelton) to stop harvesting oysters due to the naturally occurring bacteria Vibrio parahaemolyticus (Vp). A pilot program's testing for tlh (an indicator of how much Vp is present) resulted in 9,300 MPN/gram (most probable number), far above the action number of 100 MPN/gram.

Vibrio parahaemolyticus

Vp is present in Puget Sound waters year round, but warm summer months, salinity and turbidity all increase its numbers within the water column dramatically. Oysters, being filter feeders, accumulate this bacteria which is then consumed by humans, causing vibriosis [read here about Vp]. During the winter months it is found concentrated in the sediments and may be introduced into the water column through sediment disturbance.

As of yet no recalls of oysters harvested from Oakland Bay, Totten Inlet, and, Hood Canal area #8 have been issued. Illnesses traced back to oysters harvested, or testing from these areas, have indicated elevated levels of Vp to be present. The coming warm days are expected to increase the risk further.

Drakes Bay Oyster Company

Issues Recall for Infected Oysters

In the past, "after-the-fact" recalls were initiated only after an indeterminate number of people became sick.  In California, after illnesses of vibriosis were reported, the source was tracked back to oysters harvested by Drakes Bay Oyster Company between July 17 and August 8.  [read here for Drakes Bay Oyster Company recall] Washington's Department of Health is trying to be more pro-active by requiring harvesting to stop, before infected oysters enter the food stream.

Until prevented from entering into the food stream perhaps legislators and the FDA should simply require post harvest processing of oysters harvested where Vp is known to occur. The expense to the state from testing would be lessened and the economic hardships brought on by illnesses contracted from infected oysters would be minimized.