Amnesic shellfish poisoning

Amnesic shellfish poisoning (ASP) is a type of foodborne illness caused by the consumption of shellfish contaminated with domoic acid, a neurotoxin produced by certain species of algae. The condition was first identified in 1987 following an outbreak in eastern Canada, and has since been recognized in several other regions worldwide.

Symptoms

The symptoms of ASP can vary widely, but typically include gastrointestinal issues such as nausea, vomiting, diarrhea, and abdominal pain. In more severe cases, neurological symptoms may also occur, including dizziness, headache, seizures, and memory loss. In extreme cases, ASP can lead to permanent short-term memory loss or even death.

Causes

ASP is caused by the consumption of shellfish that have ingested the diatom Pseudo-nitzschia, which produces the neurotoxin domoic acid. This diatom blooms in certain conditions, leading to high concentrations of the toxin in the surrounding water. Shellfish such as mussels, clams, oysters, and scallops can accumulate the toxin when they filter feed.

Prevention and Treatment

Prevention of ASP primarily involves monitoring of shellfish beds for the presence of Pseudo-nitzschia and domoic acid, and closing the beds to harvesting when levels are high. Treatment for ASP is primarily supportive, as there is no specific antidote for domoic acid. This may include hydration, pain relief, and treatment of seizures if they occur.

See Also

• Paralytic shellfish poisoning
• Neurotoxic shellfish poisoning
• Diatom
• Domoic acid