Food poisoning from oysters generally occurs if the shellfish are tainted with bacteria, especially the type known as Vibrio vulnificus, which is common in raw shellfish. Physicians generally counsel that the best way to avoid contracting food poisoning from oysters is to avoid eating them raw. It is generally safest to prepare raw food in a clean kitchen facility, with clean hands and utensils. People who are ill, especially those who are ill with infections commonly spread through food poisoning, should generally avoid preparing food, since they could taint it. One can also help prevent food poisoning from oysters be ensuring that the oysters are as fresh as possible, and purchased from a reputable merchant who stores them in appropriately chilled, sanitary conditions.
Cooking the oysters is believed to be the best way to prevent the transmission of food poisoning when they are eaten. Even if the oysters are tainted, it is likely that cooking them will kill the pathogenic agents. Consumers are typically advised to discard any oysters that do not pop open during the cooking process, since these oysters could very likely be tainted.
Hands, utensils, and cooking areas should generally be sterilized before food preparation to prevent the transmission of food poisoning from oysters. The cooked oysters should generally be kept well away from any raw oysters waiting to be cooked. If the raw oysters come into contact with the cooked oysters, any bacteria or other pathogens within them could re-contaminate the cooked oysters.
Physicians generally believe that food poisoning from oysters and other foods, especially shellfish, is more likely during the hot months of the year, when these foods are not as likely to be kept consistently chilled. It is generally best to purchase the freshest possible oysters for consumption, especially if they are to be eaten raw. The merchant should store the oysters appropriately before sale. Certain people, such as children, senior citizens, and pregnant women, are often at higher risk for food poisoning and may be generally advised not to eat oysters at all. People with liver disease, diabetes, kidney disease, reduced immunity, or those on certain medications are also generally advised to avoid the consumption of raw shellfish like oysters, since these people could also be far more prone to contracting food poisoning from tainted food.