Rare flesh-eating bacteria on the rise in the US: Causes, symptoms, who is at risk, prevention and more

The warm temperatures of the summer are perfect breeding climates for a variety of bacteria that thrive in increasing temperatures. These developed and quickly rising bacteria are strong enough to battle the immune system and lead to severe health problems, including death.

In 2025, a rare flesh-eating bacteria led to the death of four people in Florida. These deaths are among the 11 cases of bacterial infection confirmed in the year so far. What is this bacteria and how is it fatal? Know all about it below!

What is the flesh-eating bacteria attacking Americans?

Since 2016, Florida has recorded 448 cases and 100 deaths, all because of Vibrio Vulnificus. This is a rare flesh-eating bacteria thrives in warm, brackish seawater and can cause severe infections, including necrotizing fasciitis, if it enters the body through open wounds or through the consumption of contaminated seafood, particularly raw oysters, according to state health officials.

According to the Centres for Disease Prevention and Control, the bacteria are naturally found in higher numbers from May to October, due to the warm temperatures.

How do people get infected?

Vibrio Vulnificus infections are rare, with about 80,000 Vibrio cases and 100 related deaths each year in the United States, as per the CDC. The infections are mostly caused by the consumption of contaminated raw or undercooked seafood, when an open wound comes into contact with the bacteria-infected coastal waters, or when someone swallows the water.

Who is at risk?

This year, the deaths due to the bacteria occurred in Bay, Broward, Hillsborough and St. Johns counties. Other cases have been confirmed in Duval, Escambia, Lee, Manatee, Santa Rosa and Walton counties.

The bacteria pose a high risk to individuals with weak immune systems or chronic health conditions. "People who are most at risk are immunocompromised — people with cirrhosis, people on chemo, anybody who has a compromised immune system of any kind," said Dr. Edward Hirsch, an infectious disease specialist at HCA Florida University Hospital, to CBS NEWS.

What are the symptoms of Vibrio Vulnificus?

Common symptoms of the bacterial infection include diarrhoea, stomach cramps, nausea, vomiting and fever, as per the CDC. With open wounds, symptoms can be discolouration, swelling, skin breakdown and ulcers. According to Hirsch, "It progresses to making a hole in whatever part of your body got infected."

How is Vibrio Vulnificus a flesh-eating bacteria?

The bacteria don't eat, but kill the tissue. It can not penetrate unharmed skin, but if it enters through an existing break- like a wound, it can cause necrotizing fasciitis, and the flesh around the infection site could die. Then, according to the CDC, the infected site could require a major surgery or even limb amputation.

How to prevent Vibrio Vulnificus infections?

One of the primary methods of prevention is to rinse off after swimming in ocean water and properly clean and cook seafood, as these are the two main sources of infections.

According to the Florida Department of Health and the CDC, other prevention tips include:

Stay out of saltwater or brackish water if you have a wound or cut. If you get a cut in the water, leave the water immediately.

Cover the wounds with a waterproof bandage if they come in contact with contaminated water or seafood.

Avoid cross-contamination of cooked seafood and other seafood with raw seafood.

Immediately visit a medical professional for infected wounds.

FAQs

1. What exactly is this flesh‑eating bacteria?It’s Vibrio vulnificus, a marine bacterium thriving in warm saltwater or brackish coastal waters. It can cause necrotizing fasciitis, a rapid tissue‑destroying infection—not because it eats flesh, but because it releases toxins that kill tissue.
2. How do people get infected?There are two main routes:Open wounds or cuts exposed to contaminated seawater.Eating raw or undercooked shellfish, especially oysters.The bacteria can also be absorbed if seafood juices touch an open cut.
3. Who’s most at risk—and why is this rising now?High risk groups include people with liver disease, diabetes, cancer, immunosuppression, or high iron (like hemochromatosis)––someone in these groups is 80× more likely to develop bloodstream infections.
4. What are the symptoms and how serious is this?Symptom onset is swift—within hours:Intense pain, redness, swelling at an exposed woundBlisters, darkened or purplish skinFever, chills, nausea, vomiting, diarrhea (if ingested)Rapid spread, drop in blood pressure, sepsisFatality rates reach 20–50%, especially when infection enters the bloodstream. Some cases require amputation.
5. How can you prevent it—without becoming paranoid?Don’t swim in warm coastal or brackish water with open wounds—cover them with waterproof dressings.Cook shellfish thoroughly; no raw oysters, especially for those at higher risk.Wash wounds immediately with soap and water after exposure to contaminated water or seafood. Use gloves when handling raw shellfish.Stay alert to early symptoms and seek medical care immediately if you feel off after exposure.