The Hong Kong government has given a press release about the deaths of two men from Vibrio vulnifcus on the 20th of June this year (2012) (press release). V. vulnificus is a marine bacteria which can cause infection by ingestion (seafood) or through open wounds when swimming or wading in infected waters or via puncture wounds from the spines of fish such as tilapia. It prefers warm seawater or brackish (mixed fresh- and seawater) and occurs worldwide in warm salt-bearing waters and can be present in infected shellfish. It is a relative of the bacteria that causes cholera (Vibrio cholerae).
The infection presents itself with symptoms including vomiting, diarrhea, abdominal pain, and a blistering dermatitis. In people with compromised immune systems, V. vulnificus is eighty times more likely to spread into the blood stream, when it can cause severe symptoms including blistering skin lesions, septic shock, and even death . Severe infection may occur regardless of whether the infection began via contaminated food or via an open wound. There is no evidence for person-to-person transmission.
One of the two men was found to have consumed raw mantis shrimp in an investigation. I would stress though that there seems to be no reason to assume that we are more at risk in HK than anywhere else. Infections also occur in US coastal waters, Japanese coastal waters and anywhere where infected shellfish is consumed. Given that shellfish is cold-stored and flown around the world in todays world, infections can happen almost anywhere. If you are concerned, the press release issued the following safety guidelines for the public:
People are reminded to adopt the following measures to prevent necrotizing fasciitis and Vibrio vulnificus infection:
* Avoid exposure of open wounds or broken skin to seawater or salty water;
* Wounds should be thoroughly cleaned and properly covered;
* Wear thick rubber gloves when handling raw shellfish;
* Cook seafood, especially shellfish (e.g. oysters, clams, mussels) thoroughly; and
* For shellfish, boil until the shells open and avoid cross-contamination of ready-to-eat food with raw seafood.
Patients should seek medical advice promptly if they develop symptoms and signs of infection such as increasing redness, pain and swelling.