Shellfish poisoning, amnesic-neurotoxic

Shellfish poisoning, amnesic-neurotoxic is caused by toxins produced by algae. Amnesic shellfish poisoning is caused by domoic acid. Neurotoxic shellfish poisoning is caused by brevetoxin.

CASES/YEAR
1,200 (US); 24,000 (Global)
AGENT TYPE
Toxins
OTHER NAMES
Amnesic shellfish poisoning: domoic acid; Neurotoxic shellfish poisoning: brevetoxin;
ACUITY
Acute-Severe
INCUBATION
Few minutes to hours (neurotoxic); 24 hours to 2 days (amnesic);
INITIAL SYMPTOMS
Nausea/vomiting, diarrhea, abdominal pain, and headache;
PRECAUTIONS
COMMENTS
Domoic acid was found in Atlantic shellfish in 1987. It was detected in crabs and clams in the states of Oregon and Washington, and in seafood from the Gulf of Mexico in Texas. Brevetoxin is associated with red tide off the coast of Florida. Brevetoxin usually causes a mild illness that resolves quickly. Symptoms include paresthesias, dizziness, ataxia, myalgia, and gastroenteritis. Domoic acid also causes gastroenteritis plus headache and loss of short term memory. [CCDM, p. 225-6] Domoic acid causes headache, dizziness, loss of short-term memory, confusion, seizures, and coma. Brevitoxins cause GI and neurological symptoms several hours after ingestion. [Cecil, p. 693-4] Testing several months after the intoxication may show sensorimotor neuropathy. [PPID, p. 3431]
DIAGNOSTIC
Clinical; Detection of the toxin in shellfish by high-pressure chromatography.
SCOPE
Global
SIGNS & SYMPTOMS
  • >myalgia
  • G abdominal pain
  • G diarrhea
  • G nausea, vomiting
  • N confusion, delirium
  • N headache
  • N paresthesia
  • N seizure
  • *peripheral neuropathy
  • *stupor, coma
ANTIMICROBIC

No

VACCINE

No

ENTRY
Ingestion
SOURCE
Animal Tissue, Eating Contaminated Mollusks or Crustacean
RESERVOIR
Fish and Shellfish
RISK FACTORS
  • Ingest toxins in food or water
  • Victim--air release of toxins
  • Victim--water/food release
TREATMENT
No specific antidote; [Cecil, p. 694]
REFERENCES FOR CASES/YEAR
1. (US) Every year, about 30 cases of disease caused by marine toxins are reported. These diseases include scombrotoxic, ciguatera, and shellfish poisoning (paralytic, neurotoxic, and amnesic); Some health departments test shellfish within their jurisdiction by monitoring levels of dinoflagellate toxins and may prohibit local recreational and commercial seafood harvesting when testing indicates high levels. It is estimated that about one person in the US dies every 4 years from toxic seafood poisoning. [CDC website] Guesstimate: Use cases/yr from study in Wales and divide global cases/yr by 20;
2. (Global) An analysis of all detected cases of shellfish poisoning in Wales from 1998 to 2009 found a rate of 16 cases per million per year; [Hinder2011: PMID 21645342] Guesstimate: Use the 16/million rate for the total shellfish poisoning cases = 16 X 3000 = 48,000 (24,000 for paralytic and 24,000 for amnesic-neurotoxic);