Maine CDC Press Release

August 1, 2007

Paralytic Shellfish Poisoning (Red Tide) Illnesses - Washington County

Late on July 31st, four persons from a Washington County fishing household were hospitalized with symptoms of paralytic shellfish poisoning (PSP) within several hours of sharing a meal of mussels. Samples of mussels taken from the home were highly contaminated with the toxin that causes paralytic shellfish poisoning.

Maine Center for Disease Control and Prevention (Maine CDC) sent a health alert to health care providers early this morning. Maine CDC is now assisting the Maine Department of Marine Resources (DMR) to determine the source of the implicated mussels and to assure that any harvested shellfish available to the public continue to be safe to eat. Early information indicates the probable source of the mussels was a drifting barrel found by the lobsterman off the Washington County coast; not from a mussel bed. This information also indicates the mussels taken off the barrel were for the lobsterman’s personal use.

Paralytic shellfish poisoning (PSP) – also called red tide – is a marine biotoxin that is associated with certain types of algae blooms in coastal waters. Bivalve shellfish eat and filter the toxic algae, and the concentrations of the toxin can cause serious illness or death if eaten by humans.

Consumers concerned about obtaining safe shellfish should buy from certified shellfish dealers whose operations undergo rigorous public health screening and auditing.

Symptoms of PSP include tingling of face and neck areas, headaches, nausea, and muscle weakness. In extreme cases, these symptoms can lead to respiratory failure. Symptoms usually occur within two hours of eating contaminated shellfish. Anyone who has eaten shellfish and has these symptoms should seek immediate medical care.

The Maine DMR monitors shellfish beds closely and closes areas to shellfish harvesting if levels of PSP are noted to be high. Because of this well developed system, there have been no documented cases of human PSP in Maine since at least 1980. This testing and closure system coupled with effective law enforcement has a long history of successfully preventing consumers from being exposed to shellfish from areas closed because of red tide.

The Department of Marine Resources Public Health Division routinely test shellfish along Maine’s entire coast to test for harmful red tide levels. Current red tide closure areas include the area from Cutler to the Canadian Border (not including all of Cobscook Bay), an area around Isle au Haut and Frenchboro, and part of southern Maine south of Biddeford. Department staff are conducting tests this morning on shellfish from the affected area to verify the current closure areas.