Vibrio bacteria prompts closure in Dabob Bay

Published 12:01 am Friday, August 17, 2012

OLYMPIA — The discovery of vibrio bacteria in shellfish has prompted the closure for the rest of the summer of three commercial growing areas, including one in Dabob Bay, the state Department of Health said Thursday.

The closure in Dabob Bay affects 14 commercial companies, said Richard Lillie, public health adviser in the shellfish and water safety office of the state Health Department.

The two other areas closed are North Bay, between Allyn and Victor on the Hood Canal, and Totten Inlet near Olympia.

Vibrio bacteria has caused 30 confirmed illnesses statewide this summer, the department said.

Although specific numbers of illnesses from Dabob Bay are not known, to close an area, there must have been at least four illnesses confirmed from there, Lillie said.

Growth of vibrio bacteria is common in warm weather conditions, the department said.

Once water temperatures begin to cool in October, these growing areas will reopen, it added.

People get vibriosis from eating raw or undercooked oysters that have vibrio parahaemolyticus bacteria in them.

Cooking shellfish until the shells just open is not enough to kill the bacteria.

Shellfish should be cooked to an internal temperature of 145 degrees for at least 15 seconds.

Cooked oysters shouldn’t be rinsed in seawater, which can re-contaminate them.

Vibriosis symptoms include diarrhea, stomach cramps, nausea, vomiting, headache, fever and chills.

Symptoms usually appear within 24 hours of eating infected shellfish and can last two to seven days.

Vibriosis can be life-threatening for people with low immunity or chronic liver disease.

Also at greater risk are people who take antacids, heart or diabetes medication, or who have had antibiotic or cancer treatments recently.

The closures announced Thursday were for commercial growing areas.

Recreational harvest

Recreational harvesting was closed on numerous North Olympic Peninsula beaches earlier this summer because of elevated levels of marine biotoxins that cause paralytic shellfish poisoning, or PSP, or diarrhetic shellfish poisoning, or DSP.

Such closures have affected “a significant amount of Jefferson County’s shoreline,” the department said, as well as beaches on the Strait of Juan de Fuca from Dungeness Spit west to Cape Flattery in Clallam County.

For information on recreational closures, phone 800-562-5632 or visit www.doh.wa.gov.