What’s going on?
Vibrio are bacteria that live in coastal waters with a preference for warm, brackish areas where ocean water and freshwater mix. Vibrio bacteria are naturally occurring and not associated with any kind of pollution. When humans come in contact with Vibrio bacteria, whether by consuming raw shellfish or entering the water with an open wound, they can develop an infection called vibriosis.
Many types of Vibrio exist. One such species is the bacterium that causes cholera. Another common species is Vibrio parahaemolyticus, which can be found in shellfish that live in brackish water. Cooking shellfish kills this bacterium, but consuming raw shellfish like oysters can lead to a greater risk of infection. This type of Vibrio infection can lead to gastroenteritis (stomach flu) for 2-3 days.
Vibrio vulnificus is the most dangerous Vibrio bacterium. Once it has infiltrated a pre-existing wound, this bacterium can cause necrotizing fasciitis, killing surrounding flesh. Early treatment with antibiotics or surgery can help stop the infection, but left untreated the infection can lead to amputation or death. The Centers for Disease Control and Prevention (CDC) estimate that in the U.S., around 20% die once infected by this bacterium.
Why it matters.
Vibrio bacteria thrive in warm brackish environments, making Florida waters an effective breeding ground. In fact, Florida has the highest incidence of vibriosis in the U.S., with 20% of Florida’s cases coming from the Indian River Lagoon.
Recent studies show that climate change may increase rates of Vibrio infections. As ocean temperatures rise, higher concentrations of Vibrio bacteria may be present at more northern latitudes than before.
Severe hurricanes, which may increase in frequency due to climate change, can exacerbate the Vibrio issue through storm surge flooding. Following Hurricane Ian in 2022, 38 people were sickened and 11 people died from Vibrio bacteria in Lee County, which was the highest number of Vibrio cases in a single month in Florida in over 30 years. With climate change and rising temperatures threatening Floridians every year, it is possible that Vibrio infections might become a more serious problem.
What you can do.
Avoid vibriosis:
- Do not get in brackish/ocean water with open wounds or scrapes.
- Do not prepare raw seafood with an open wound.
- Avoid eating raw shellfish, especially during the summer months when warm waters create a more hospitable environment for Vibrio bacteria.
- After hurricanes, avoid entering flooded areas. Floodwaters could contain sewage, chemicals, and sharp objects that could inflict injuries for Vibrio bacteria to infect.
If you are immunocompromised or have a history of liver disease, try to avoid exposure to Vibrio entirely. While the body can fight off some cases of vibriosis on its own, these preexisting conditions make it much easier for the bacteria to cause a serious infection.
If you believe you may have a Vibrio infection, contact your medical provider immediately.