A fourth person has died in Florida of an infection caused by "flesh-eating" bacteria, according to the state's health department.
Vibrio vulnificus, a bacterium commonly contracted by eating raw seafood or exposure to brackish coastal waters, is known as "flesh-eating" because it can cause vibriosis, a severe infection that destroys skin and soft tissue. Florida reports infections every year, with cases typically resulting in a small number of deaths. Flooding caused by major storms, including hurricanes Helene and Ian, has been linked to spikes in infections and fatalities.
The state has recorded 21 cases so far this season as of Sept. 10, according to Florida health data, and four deaths in Bay, Broward, Marion and Palm Beach counties. It reported
33 total cases and five deaths in 2025.
A handful of vibriosis cases have also occurred in Louisiana this year, which reported six deaths as of Sept. 16.
While Vibrio vulnificus infections are uncommon, they can become life-threatening within days, particularly for people with weakened immune systems. About 1 in 5 people who develop the infection die, according to the Centers for Disease Control and Prevention (CDC).
The CDC estimates that 100 to 200 cases of vibriosis caused by Vibrio vulnificus are reported in the United States each year, with most occurring in Gulf Coast states. Other Vibrio species are far more common, with roughly 80,000 infections annually.
Peak Vibrio vulnificus season usually ends in October, according to the Louisiana Department of Health.
What is Vibrio vulnificus?
Vibrio vulnificus is a bacterium that causes a serious infection called vibriosis. Different types of Vibrio bacteria cause different infections. Vibrio vulnificus is one of the "most serious forms of vibriosis," according to the Cleveland Clinic.
The potentially fatal infection can quickly result in tissue damage and spreading blisters, low blood pressure, fever, organ damage, sepsis and death.
Vibrio vulnificus is often referred to as "flesh-eating" because it can also cause necrotizing fasciitis, which is a bacterial infection that destroys muscle and skin tissue and can cause flesh around wounds to die, according to the CDC. Vibrio vulnificus is not considered the most common cause of necrotizing fasciitis in the United States, however.
The bacteria and resulting infections are rare but can be life-threatening. Without treatment, patients can die in just a few days.
How do 'flesh-eating' bacteria enter the body?
Vibrio vulnificus requires salt water for survival and thrives in warm, brackish water where a stream or river meets seawater, according to the CDC.
Raw or undercooked shellfish, especially raw oysters, are the most common source of infections tracked by the CDC. Infections also commonly occur when contaminated water is swallowed or gets into an open wound, such as a cut or scrape. The bacteria can enter through broken skin but cannot penetrate intact skin.
Once inside the body, the infection can spread to the blood and organs, usually within hours.
Symptoms of a Vibrio vulnificus infection begin suddenly and quickly, usually less than 24 hours after exposure, according to the CDC and the Cleveland Clinic, and can include fever, rapid heartbeat, low blood pressure, nausea, vomiting, diarrhea, and a rash that is red, warm, swollen, painful, and spreads quickly.
How to protect yourself against Vibrio vulnificus
When consuming seafood, the CDC advises that you should:
- Cook seafood, including oysters, before consuming.
- Thoroughly clean surfaces that may have come in contact with raw seafood and its drippings.
- Wash your hands thoroughly after handling raw seafood. If you are at high risk, wear gloves.
When swimming, you should:
- Avoid entering salt water or brackish water if you have any open wounds. That includes recent surgical sites, fresh tattoos and piercings, and even minor cuts or scrapes.
- Cover any open wounds if you may come into contact with coastal waters or raw seafood, even if you don't plan to be directly exposed to either. Exposure can also occur during storm-related flooding.
- Immediately wash any area of open skin with soap and running water after contact with coastal water or raw seafood.
- If you are at increased risk (people with weakened immune systems and conditions like liver disease, diabetes and kidney failure), wear protective shoes and clothes when in or near coastal waters.
Contributing: Janet Loehrke, USA TODAY; C.A. Bridges, USA TODAY NETWORK - Florida
This article originally appeared on USA TODAY: Rare 'flesh-eating' bacteria causes 9 deaths this season. See where
