Raw oysters, a delicacy for foodies and a purported hangover cure (it isn’t) aren’t always the safest thing to eat. Pathogens such as Vibrio vulnificus, norovirus and Hepatitis A sometimes lurk in oyster flesh. These little nasties can cause food poisoning and norovirus specifically has no treatment or vaccine, and can result in serious illness or even be fatal because of the dehydration it causes via diarrhea and vomiting. According to the Centers for Disease Control, norovirus infects some 20 million people yearly.
To combat these pathogens, oysters are usually pasteurized with one of several methods, most involving heating and freezing or high pressure. But pressure and heating are old hat and don’t always kill all of the bacteria and/or viruses present.
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