Vibrio Bacteria Levels Continue to Climb - Hammersley/Totten Inlets Closed to Commercial Harvesting of Oysters

Update 7/21: Vibrio levels continue to climb and expand. The Department of Health has announced that testing for Vibrio levels has closed most of Hood Canal to commercial shellfish harvesting of oysters. This is now in addition to Hammersley and Totten Inlets. Oakland Bay's level of Vibrio was just below the 10,000 mpn level and remains open to harvesting.

 

Washington shellfish growing areas

closed to commercial harvesting of oysters

as of July 19.

 

 

Closed to commercial shellfish harvesting of oysters

 

Low tides and warm temperatures = warmer water

Following low tides and warm weather Washington's Department of Health testing found Vibrio parahaemolyticus (Vp) exceeded safe levels and has closed Hammersley Inlet and Totten Inlet to commercial harvesting of oysters. Hammersley Inlet testing found levels of 110,000 mpn (most probable number). Totten Inlet testing found levels of 15,000 mpn. Last week similar levels were found in southern Hood Canal which resulted in that area also being closed. Levels above 10,000 mpn result in an automatic closure.

 

Bacterial blooms

Vp is a naturally occurring bacteria which oysters filter from the waters of Puget Sound and retain internally. When the waters of Puget Sound increase in temperature and tides are low during warmer summer days Vp blooms to a level oysters become unsafe to eat.

 

 

2013 Reported Cases from Atlantic States

(from CDC, April 18, 2014)

Past reported cases:

2011 - 6; 2012 - 52; 2013 - 104

(from CDC, October 21, 2013)

  

East Coast and West Coast Effected

In the past it was felt the bacteria was primarily a northwest shellfish problem but last year demonstrated that shellfish growing areas on the east coast now also face the same problem. Illnesses from east coast oysters increased to such a level last year that Massachusetts and Connecticut both issued recalls for oysters harvested from those states. An April 18, 2014, Center for Disease Control (CDC) paper noted:

In the United States, Vp causes an estimated 35,000 domestically acquired foodborne infections annually (1), of which most are attributable to consumption of raw or undercooked shellfish.

Learn how to minimize risk

Enjoy life, minimize risk
Life has risks in all we do. Knowing how to minimize those risks will allow you to enjoy life. Visit Washington's DOH "Illness Prevention" website for more information on shellfish safety.