In recent months, food poisoning cases have been reported which were suspected due to the consumption of raw crabs marinated with soy sauce and wine (also known as "drunken" crabs). What are the food safety risks of consuming these raw crabs?

Raw crabs may contain different pathogens, including bacteria (e.g.Vibrio cholerae and Vibrio parahaemolyticus) and parasites (e.g. Paragonimus westermani, also known as lung fluke). Using ingredients such as wine, vinegar, soy sauce, garlic, chilli to marinate crab cannot eliminate these microorganisms. Cooking the food thoroughly is the only way to prevent diseases caused by these pathogens.

Depending on the types of pathogens, consumers may get different diseases and have different symptoms after eating contaminated marinated raw crabs. For example, Vibrio cholerae can cause cholera with symptoms like severe diarrhoea and vomiting, which may lead to dehydration. If treatment is delayed, cholera could be fatal. On the other hand, lung fluke can migrate within the body for some time, most often ending up in the lung to cause lung disease , and sometimes can travel to the brain where it can cause symptoms of meningitis. Onset of symptoms of lung fluke infection usually occurs many weeks after exposure and disease may last for many years. Other pathogens, such as Vibrio parahaemolyticus, can cause food poisoning with symptoms including diarrhoea, abdominal pain and fever. 

For the sake of safety, the public should avoid eating marinated raw crabs.

Suspected food poisoning case related to the consumption of raw seafood investigated by the Department of Health: http://www.info.gov.hk/gia/general/201505/13/P201505131018.htm