Four people have died from Vibrio vulnificus — a type of bacteria that can cause a life-threatening infection — in Florida so far this year, the Florida Department of Health announced.
The bacteria, which have been nicknamed “flesh-eating bacteria,” are naturally found in warm, brackish seawater. Vibrio vulnificus infections are rare, but they can be fatal if left untreated.
The United States typically sees 100 to 200 cases each year. So far, 11 people have contracted the infection in Florida this year. Last year, there were 82 cases and 19 deaths in Florida — a surge likely caused by Hurricane Helene.
The bacteria thrive in water between 59-104 degrees Fahrenheit. So warmer temperatures — which are becoming more common due to climate change — create ideal conditions that help the bacteria proliferate.
“In Florida, we typically have cases seen each year but it appears an increase in cases is being seen,” Dr. Norman L. Beatty, an associate professor of medicine in the division of infectious diseases and global medicine at the University of Florida College of Medicine, told HuffPost.
How do you get a Vibrio vulnificus infection?
There are two ways you can be exposed to Vibrio vulnificus. The first is by consuming uncooked or undercooked shellfish, like oysters.
The second method is by entering affected seawater with an open wound. Bacterial levels are typically highest in coastal waters between May and October, when temperatures are the warmest, according to the Centers for Disease Control and Prevention (CDC).
The vast majority of cases occur when the bacteria enter an open wound, but about 10% are caused by undercooked seafood, according to the University of Florida.
Infections tend to spike during and after hurricanes. According to research from the University of Maryland, intense rainfall, changes in seawater temperature, and an increase in chlorophyll levels in the water (which indicate there may be nearby plankton blooms) can lead to an “abundance of Vibrio bacteria.”
Hurricane Helene in 2024 and Hurricane Ian in 2022 both led to an abnormal spike in Vibrio vulnificus cases. The cases in Florida documented this year do not appear to be related to any weather events, Beatty said.
While the bacteria are more prevalent in Florida, they exist in other regions, too. “It’s more common in Florida because of the warm coastal waters, but cases can happen in other Gulf Coast and East Coast states during the summer, even as far north as New England,” said Dr. Daniel D. Rhoads, chair of the College of American Pathologists Microbiology Committee.
What are the symptoms like?
Symptoms of Vibrio vulnificus infections appear suddenly, often within 24 hours of being exposed to the bacteria. People typically experience fever, chills, dizziness and confusion.
If you ingested uncooked seafood, you may develop gastroenteritis and experience nausea, vomiting and diarrhea. But if the bacteria entered a wound, you may develop a rash near the site of the wound that quickly becomes swollen and painful. You may also notice fluid-filled blisters.
“If a person develops blistering at the site of infection, which we call bullae, this indicates the tissue is dying and a person should immediately go to a hospital,” Beatty said.
The wound infection, known as necrotizing fasciitis, “eats away at human flesh,” the University of Florida states.
Some people may experience “a rapidly progressing soft tissue infection that can spread systemically and cause sepsis and septic shock,” said Dr. Amesh Adalja, an infectious diseases expert and senior scholar at the Johns Hopkins University Center for Health Security.
Healthy individuals typically develop a mild form of the disease. But people who are immunocompromised — such as those with chronic liver disease, diabetes, or iron overload — face a higher risk of both sepsis and soft tissue infection, Adalja said.
One study found that people with underlying health conditions are 80 times more likely to develop Vibrio vulnificus bloodstream infections than healthy people. Roughly 50% of Vibrio vulnificus bloodstream infections are deadly.
Overall, about 20% of cases in the U.S. are deadly. “Vibrio vulnificus wound infections are somewhat unusual in that they can worsen quickly and can be life-threatening,” Rhoads said.
What’s treatment and recovery like?
If you experience any of the above symptoms and suspect you were exposed to the bacteria, it’s crucial to seek medical help immediately. “The infection can be quite fulminant if not recognized and treated early,” Adalja said.
Vibrio vulnificus is typically diagnosed via stool, wound or blood cultures. The infection is primarily treated with oral antibiotics. They are effective at preventing severe disease, Beatty said.
In severe cases, surgery may be necessary to remove infected soft tissue. According to University of Florida, early treatment is crucial and helps prevent the need for surgery or even amputation.
How can you protect yourself from Vibrio vulnificus?
We are now in hurricane season, which has been associated with an uptick in Vibrio vulnificus activity. As such, it’s crucial to be prudent and prepared, Beatty said.
The best thing you can do is avoid going into the ocean if you have an open wound or recent piercing. As the Florida Department of Health states, “Water and wounds do not mix.”
This advice is crucial for people at high risk of severe infections, Adalja said. If you develop a wound while you’re in the water, get out and immediately clean it with sterile water, Beatty advised.
And if you’re a fan of seafood, the safest bet is to cook your shellfish, oysters and mussels thoroughly. Wear protective clothing — like gloves — when handling raw shellfish. Vibrio vulnificus infections can become serious quickly, but they can be easily prevented by following these simple steps.