Food safety professionals from 12 African countries met in Kenya for a workshop on seafood safety.

The African regional workshop on bivalve mollusk sanitation was held in Nairobi this past month and included visiting experts from the United Kingdom, Italy and Canada.

The aim was to build programs of capability building and networks in Africa for authorities and official laboratories in countries wishing to develop or expand production for domestic consumption or trade reasons.

Of the 16 million tons of bivalves produced annually only 500,000 tons are traded outside the country of production. Barriers can be product safety, compliance and equivalence with legislation between countries.

A product often eaten raw
Wild caught and aquaculture bivalve mollusks such as oysters, clams and scallops provide employment in coastal communities, particularly for women but can pose risks to the consumer from bacteria such as Salmonella and Vibrio, viruses including norovirus and Hepatitis A and parasites like Giardia and Cryptosporidium.

The workshop was hosted by the Food and Agriculture Organization of the United Nations (FAO) Reference Centre for Bivalve Mollusc Sanitation, which is based at the U.K.’s Centre for the Environment, Fisheries and Aquaculture Science (Cefas) and the FAO’s Fisheries and Aquaculture Policy and Resources Division.

Dr. Rachel Hartnell, of Cefas, and the FAO Reference Centre lead, said bivalve mollusks are considered a high risk foodstuff because they take on the characteristics of their growing area via filter feeding so tend to concentrate microorganisms, toxins and chemicals in the environment and safety management requires stringent sanitary measures.

“If harmful microorganisms, mainly from human or animal waste, are present in that growing area they can concentrate in bivalve tissues, the potential health risks are compounded because bivalves, particularly oysters are often eaten raw. Globally risks are controlled via food safety legislation which focuses on assessments of risk using indicators of fecal contamination (e.g. nonpathogenic E. coli or fecal coliforms – present in human and animal sewage) to predict the likelihood of the presence of pathogens in the growing areas,” she told Food Safety News.

Non-notifiable conditions
Hartnell said the main approaches used are either monitoring fecal indicators directly in bivalve tissues or in the growing area water to provide risk based control measures to protect public health.

“Recently advances in science and technology have enabled direct detection of human enteric pathogens like norovirus and hepatitis A virus using quantitative real time PCR, in some countries traditional indicator approaches are complimented by these newer technologies with the aim of providing enhanced health protection,” she said.

“In many countries and including many in Africa, epidemiology for non-notifiable often foodborne illnesses is scarce, consequently very little information is available on the scale of public health problems associated with seafood. What we do know is that there is a good awareness amongst African competent authorities around potential risks, and that community outbreaks of illness that we observe elsewhere in the world associated with bivalves are not uncommon in Africa.”

The risk posed by different hazards should be assessed based on factors such as pollution sources affecting the growing area, seasonality of harvest, water temperature and salinity, method of processing of finished shellfish and epidemiological data on pathogens in the population. Testing samples of shellfish or water involves complex methods and may require specialist labs.

It was the first meeting of the FAO Reference Centre for Bivalve Mollusc Sanitation internationally to work with seafood safety organizations. Participating countries were Angola, Cameroon, Ghana, Gambia, Djibouti, Kenya, Madagascar, Mauritius, Mozambique, Senegal, South Africa, and Sudan.

Access to international markets
Seafood safety systems in Africa range from very advanced to fairly basic, said Hartnell.

“All countries at the workshop have a very good awareness of the issues and share a goal to enhance safe bivalve production for either domestic consumption or international export. The aim of the work of FAO and Cefas, starting here, is to build and support this network, sharing best practice, providing access to protocols, methods, materials and online and physical training to help them in achieving their goal.”

The Reference Centre for Bivalve Mollusc Sanitation was established by the FAO at Cefas in 2018 with a remit to support UN member countries in enhancing safe production of bivalves.

Dr. Esther Garrido Gammaro, associate professional officer at the Fisheries and Aquaculture Department of the FAO, said, though bivalve mollusks are traded internationally in different forms such as fresh, chilled or frozen or canned, very few countries are able to access international markets due to stringent requirements.

“Globally, 97 countries have been authorized to export fishery products to the largest seafood market – the European Union, but only 14 of them have been authorized to export the high value commodity of live bivalve mollusks,” she said.

“Even the largest producer of bivalve mollusks in the world, China, which accounts for about 80 percent of global aquaculture production of bivalves, does not figure in the list of countries authorized to export live bivalves to the EU market. The challenge faced by exporting countries is evidenced by the fact that there are considerable number of rejections due to sanitary issues.”

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