Food poisoning warning over Coromandel mussels
A warning has been issued after a spate of food poisoning from commercially grown Coromandel mussels.
“The majority of people who have become sick have bought commercially-grown New Zealand mussels harvested from a single growing area in the Coromandel and were eaten raw or partially cooked,” says New Zealand Food Safety's director of food regulation Paul Dansted.
Over the past six weeks, there has been an increase in cases of people with food poisoning caused by Vibrio parahaemolyticus.
“This growing area has been closed by New Zealand Food Safety while further investigations continue,” says Paul.
New Zealand Food Safety is urging people to ensure they cook raw mussels thoroughly after the increase in cases of food poisoning became associated with the commercially grown New Zealand mussels.
Vibrio parahaemolyticus is a marine microorganism that occurs naturally throughout the world. Not all Vibrio parahaemolyticus strains cause illness in humans and surveys to date of New Zealand shellfish have found very low levels and incidence of disease-causing strains.
However, some strains do cause illness in humans. Symptoms are predominantly stomach cramps and watery diarrhoea and sometimes nausea, vomiting and fever. Generally people who are sick recover without hospital treatment, however, in severe cases hospitalisation is required.
"Additional testing is being done to confirm the type of Vibrio parahaemolyticus that has caused this illness,” says Paul. “It is possible that the strain of Vibrio parahaemolyticus is unusually aggressive which may mean that even low numbers could cause illness.
"Additional testing of mussels and the waters that they are being grown in is also underway to help us understand why this has happened.
"The mussels at the centre of the outbreak were all bought in their raw state, in the shell. They are not the mussels that can be bought in plastic pottles. Those mussels are cooked and marinated and are not affected.”
NZ Food Safety is reminding people to take care when handling, preparing, and consuming mussels, particularly until more information is available.
Mussels should be cooked above 65°C. This will ensure that any Vibrio parahaemolyticus that is present in mussels will be destroyed.
NZ Food Safety advise that people should not eat raw or undercooked mussels or other shellfish, but they must be cooked before eating. Hands should be washed with soap and water after handing raw shellfish, and avoid cross-contaminating between cooked shellfish and raw shellfish and its juices.
New Zealand Food Safety's advice to consumers who are pregnant or have low immunity is to avoid eating raw shellfish.