Paralytic shellfish poisoning

Paralytic shellfish poisoning is a foodborne marine-toxin syndrome caused by eating shellfish contaminated with saxitoxins produced by dinoflagellates ^[1]. The syndrome is one of the recognized shellfish poisoning illnesses primarily associated with bivalve mollusks, which are filter feeders that accumulate neurotoxins such as saxitoxin from microscopic algae, including dinoflagellates, diatoms, and cyanobacteria ^[2].

Poisoning results in gastrointestinal and neurologic illness of varying severity, with symptoms typically appearing 30–60 minutes after ingestion of toxic shellfish, although onset can be delayed for several hours ^[1]. Clinical manifestations can include gastrointestinal, neurologic, cardiovascular, or respiratory effects, and severe cases may progress to ataxia, paralysis, respiratory failure, or death ^[1]. Diagnosis is generally made clinically on the basis of a recent history of shellfish consumption ^[1].

Paralytic shellfish poisoning occurs worldwide and is especially reported in temperate waters off Atlantic and Pacific North America, including Alaska, with cases also reported in the Americas, Asia, Europe, Australia, and New Zealand ^[1]. Marine toxin poisoning from ingesting seafood is considered an underrecognized hazard, and the true burden of cases is likely substantially underestimated ^[1]. Climate change, coral reef damage, expanding international trade and tourism, growing seafood consumption, and the spread of toxic algal blooms are all contributing to an increasing risk of marine toxin exposure globally ^[1].

1. 1US Centers for Disease Control and Prevention. Food Poisoning from Marine Toxins | CDC Yellow Book™ [Internet]. cited 3 Sept 2026.Available from: https://www.cdc.gov/yellow-book/hcp/environmental-hazards-risks/food-poisoning-from-marine-toxins.html
2. 2Wikipedia contributors. Paralytic shellfish poisoning - Wikipedia [Internet]. Wikipedia. cited 3 Sept 2026.Available from: https://en.wikipedia.org/wiki/Paralytic_shellfish_poisoning