Oysters for raw consumption are a high-risk food as there is no heat treatment to kill pathogens before eating. Besides those sold alive, raw oysters available in the local market are often pre-shucked in either frozen or chilled forms. If not handled properly, it can lead to bacterial contamination and deterioration of the shellfish.
Frozen raw oysters have to be defrosted in the refrigerator to avoid exposure to dangerous temperatures. Defrosting in the fridge can take a long time, usually overnight. During defrosting, raw oysters should be stored in containers to avoid cross-contamination. Avoid eating chilled raw oysters pre-shucked at the exporting countries without cooking, as they were killed and susceptibie to temperature abuse and cross-contamination during production and transportation.
Pregnant women, infants and young children, the elderly and people with weakened immunity should avoid consuming raw or undercooked oysters.