People enjoy oysters because they are tasty and nutritious. Uncooked oysters, however, are high-risk foods, and there are occasional reports of food poisoning outbreak related to the consumption of raw oysters in Hong Kong.

Oysters are filter feeders. They constantly draw in water and accumulate substances from it, including disease-causing microorganisms such as Vibrio bacteria, norovirus and hepatitis A virus, as well as chemical contaminants and natural toxins.

 Eating raw oysters carries inherent food safety risks as there is no heat treatment to kill foodborne pathogens. Food poisoning cases related to raw oysters are reported locally from time to time. Although most of the patients suffer from mild symptoms such as diarrhoea, abdominal pain and vomiting, and recover on their own, raw oysters can also cause severe health consequences, especially in susceptible individuals.

Further, people are more likely to contract microorganisms with antimicrobial resistance ('superbugs') through eating raw or undercooked oysters. Whether or not 'superbugs' can cause illnesses, they may transfer their antimicrobial resistance genes to other bacteria inside the human body, therefore affecting the effectiveness of future use of antibiotics when needed.

Whichever type of oyster is purchased, consumers can ensure food safety by always following the steps below when choosing, storing, preparing, cooking and consuming oysters.




Periodical and Publication

Food Safety Focus

Short video

Related information