Transmission

Transmission to people usually occurs by ingestion of toxic shell fish or the inhalation of toxins. To avoid stay away from beaches that appear to be affected with a Red Tide. Also do not eat infected shellfish during a Red Tide. If shellfish is ingested flu like symptoms will occur for a few days.

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Toxic Shell fish!http://www.fishing.net.nz/toxic-shellfish-warning-in-place-from-tairua-to-pukehina/

According to Lerner, "Paralytic, diarrhetic, and amnesic shellfish poisoning all have the capability of making large numbers of people ill and can cause death in cases of extreme exposure or sensitivity. Because of the risks of poisening associated with eating marine shellfish, many countries routinely monitor the toxicity of these foods using various sorts of assays" (2004, p.3389-3390)