The Ministry of Fisheries and Marine Resources herewith warns the general public not to consume mussels originating from the Walvis Bay Aquaculture Production Area.

Mussel samples from the Walvis Bay Aquaculture Production Area have been tested for biotioxins during the most recent official sampling and testing facilitated by the Namibian Standards Institution (NSI) as part of the National Shellfish Sanitation Programme. The latest test results from the mussel samples that were submitted for testing indicate the presence of Diarrhetic Shellfish Poisoning (DSP) at a level higher than the permissible level in these samples and therefore it is unsafe to collect and consume mussels until further notice by the Ministry. Members of the public should note that marine biotixins are not destroyed by cooking or freezing.

Diarrhetic shelfish poisoning (DSP) is one of the four recognized symptom types of shellfish poisoning, the other being paralytic shelfish poisoning, neurotoxic shelfish poisoning and amnesic shelfish poisoning. As the name suggests, this syndrome manifests istself as intense diarrhea and severe abdominal pains. Nausea and vomiting may sometimes occur too.
DSP and its symptoms usually set in within about half an hour of ingesting infected shelfish, and last for about one day. The causative poison is okadaic acid, which inhibits intestinal cellular dephosphorylation. This causes the cells to become very permeable to water and causes profuse, intense diarrhea with a high risk of dehydration. As no life-threating symptoms generally emerge from this, no fatalities from DSP have ever been recorded.
When any of the above symptoms occur after eating molluscan shelfish then seek immediate medical assistance and inform the medical practisioner that you have consumed molluscan shelfish.