Friday, December 1, 2023

Public Health Prohibits Mussel Harvesting to Protect Against Paralytic Shellfish Poisoning

The following is a press release issued by Mendocino County Public Health:

California mussels [Photograph from KQED]

The California Department of Public Health (CDPH) has issued a Mussel Quarantine Order effective May 1 through October 31, 2023. The mussel quarantine is a yearly event prohibiting the public from harvesting mussels for human consumption due to potentially dangerous levels of biotoxins that may be present in shellfish anywhere on the California coast, including bays, inlets and harbors. The annual mussel quarantine is in place to protect the public against paralytic shellfish poisoning (PSP) and domoic acid poisoning, also known as Amnesic Shellfish Poisoning. 

The quarantine applies only to sport-harvested mussels. Other types of bivalve shellfish, including oysters and clams, and commercially harvested mussels from certified companies are not included in the quarantine. 

CDPH may begin the quarantine early, or extend it, if monitoring results indicate the presence of dangerous levels of biotoxins outside of the normal quarantine period. The May through October quarantine period encompasses more than 99 percent of all PSP illnesses and deaths reported in California since 1927. 

The mussel quarantine is in effect along the California coast, from the Oregon border to the Mexican border. All bays, inlets, and harbors are included. 

Notices will be posted in public areas along the coast advising the public of this quarantine.  

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PSP and domoic acid poisoning are immediately reportable to the local health authority (Title 17,  California Code of Regulations, Sections 2500). Even suspected cases should be reported immediately by telephone to the local health department and to the nearest poison control center. Local health departments should interview patients regarding shellfish exposure and report these cases promptly to the Infectious Diseases Branch at (510) 620-3434. 

For more information, CDPH has developed a “Frequently Asked Questions” (FAQ) for the annual mussel quarantine that can be found online at the CDPH Marine Biotoxin Monitoring Program website. 

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  1. Another crazy closure by fish and game……. only sport caught mussels are affected……oysters and clams aren’t affected but filter same water.
    Understand oyster farms do weekly testing but if their meat tests come back good then mussels in same area should also be good. G==rrrrrrrrr

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MendoFever Staff
MendoFever Staff
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