More than 2.5 million Coffin Bay oysters have been recalled by Food Standard Australia and New Zealand (FSANZ) following a bacterial outbreak caused by environmental conditions. The recall is for 4 September to 16 November, with the South Australian Department of Health and Wellbeing (DHW) reporting 56 cases of people falling ill and three people hospitalised.
DHW deputy chief public health officer Dr Chris Lease said: “This recall is an additional safety measure on top of the precautionary closure of the Coffin Bay Growing Area recently imposed by the Department of Primary Industries and Regions (PIRSA).”
Lease said the department has been closely monitoring case numbers since September and had confirmed the condition of vibrio parahaemolyticus present in the Coffin Bay oysters.
“Food borne vibrio parahaemolyticus infection causes symptoms of gastro, including diarrhoea, abdominal cramps, nausea, vomiting, fever and headache, and usually occurs within 24 hours of eating the contaminated food,” said Lease.
Vibrio parahaemolyticus can occur in the water or supply chain when specific temperatures create a suitable environment for bacteria to grow. This can be prevented through strict maintenance of the cold chain post-harvest, product sampling and other food safety controls.
The PIRSA closed the Coffin Bay oyster production area on 16 November which is expected to remain until early next week.
PIRSA executive director of biosecurity Nathan Rhodes said no oysters can leave the area to ensure the ability to trace cases and pursue further investigations.
“PIRSA has consulted with industry, who have supported the closure, and has been working with SA Health on the public health impacts of the outbreak.
“Many growers had already voluntarily closed their harvesting operations,” said Rhodes.
Audits of all onsite oyster production will be conducted by the PIRSA, including the supply chain, logistic providers, and handling practices in the Coffin Bay region. Cold chain maintenance to prevent further outbreaks upon the reopening of the bay will be the main focus of the audit.
South Australian, ASX listed Angel Seafood is one of the Southern Hemisphere’s largest pacific oyster.
The company said based on the average shelf-life of oysters most of the 2.6 million units harvested and sold over the recall period would have been consumed.
The oyster producer is working with authorities through its traceability technology across its supply chain to quickly identify and isolate any cases.
The company is continuing to sell oysters from its bays located outside of Coffin Bay and has complied with the PIRSA’s audits and is working with its customers to establish the amount of stock the company still possesses which is subject to the recall.
FSANZ has advised all consumers to not eat raw oysters, fresh and frozen from Coffin Bay. The authority said all consumers should dispose of the oysters purchased from the region or return them for a complete refund.
According to the DHW, individuals with liver diseases and lowered gastric acidity should avoid eating raw oysters as they are more at risk to vibrio parahaemolyticus.
Rhodes added that they are working closely with the industry to ensure a safe supply of oysters to the South Australia market through practice quality controls.
“PIRSA continues to work with the South Australian Oyster industry as we investigate the likely cause of this current outbreak,” he said.
PIRSA recommends that raw unshucked Pacific oysters should be stored at less than ten degrees Celsius and shucked Pacific oysters to be stored at less than 5 degrees Celsius to avoid contracting the illness.
