Oyster and black mussel production at Walvis Bay has been halted due to another outbreak of diarrhoeatic shellfish poisoning (DSP), which can be harmful to human beings.
The Ministry of Fisheries and Marine Resources issued a notice yesterday, warning people not to eat oysters or mussels from Walvis Bay. This comes three months after the last outbreak, which was cleared shortly thereafter.
According to fisheries biologist, contamination is a seasonal occurrence - mainly during summer from October to April.
The recent outbreak could put a dent in the shellfish industry's economy as most exports are to Asia.
The worst affected area is at Walvis Bay's central production sector called 'aquaculture production area 1', which is situated near Pelican Point.
Once two 'negative' results of tested samples are issued, the alert would be withdrawn, and harvesting, consumption and exports would be cleared again. The samples should be taken at 48-hour intervals, the statement from the ministry noted.
Marine biotoxins are not destroyed by cooking or freezing.
The statement indicated that DSP symptoms in humans who may have been poisoned might include, as the name suggests, diarrhoea, although nausea, vomiting and stomach cramps are also common.
These symptoms could manifest themselves after about half an hour of eating the infected shellfish, and could last a day. No deaths have been recorded from DSP to date, the statement indicated.
People who show such symptoms should immediately consult a doctor or healthcare centre.