Louisiana has confirmed nine cases of Vibrio vulnificus infections this year, with five deaths, prompting health officials to urge beachgoers to take precautions during a summertime surge of the flesh-eating bacterium found in coastal waters.
All nine patients were hospitalized, according to a news release from the state's health department last week. This compares to an average of seven cases and one death during the same period over the previous decade.
Health advisory and symptoms
Officials advised: "Seek medical care immediately if a wound exposed to brackish or salt water becomes red, swollen, painful, warm or discolored."
Vibrio bacteria thrive in seawater and in the brackish mix of fresh and saltwater found in estuaries and lagoons. Most infections occur from May to October, predominantly in states along the Gulf coast. Doctors say the Gulf provides an ideal environment with the right salt and heat levels for the organism to proliferate.
Deadly strain and risk factors
The most deadly type is Vibrio vulnificus, according to the Centers for Disease Control and Prevention (CDC). As many as one in five infections are fatal, a significantly higher rate than other Vibrio bacteria types.
While infections remain rare compared to other infectious diseases, once the bacterium enters the body, it can cause bruising, swelling, and decay within hours, potentially leading to septic shock and death unless treated rapidly with powerful antibiotics.
Last year, Louisiana recorded five deaths from the bacterium among at least 26 infected individuals, all hospitalized. One victim, Basil Kennedy, 77, died three days after scraping his leg on a boat trailer and entering the water.
Regional impact and transmission
Florida has reported 14 Vibrio vulnificus cases and two deaths so far this year, compared with 33 cases and five deaths for all of last year.
Some people become infected by eating raw or undercooked shellfish, particularly oysters. However, a large percentage contract the illness when the bacteria enter through small breaks in the skin during ocean or brackish water exposure.
Doctors note that severe cases are more common in elderly patients, individuals with weakened immune systems, and those with liver disease, diabetes, or certain chronic illnesses.
Climate crisis and northward spread
Scientists attribute the proliferation and northward spread of the bacteria to the climate crisis. As oceans warm, Vibrio concentration in seawater rises, increasing infection risk.
A 2023 study found the northernmost case has been shifting by about 30 miles each year, with overall cases rising. Over time, this northward movement might bring infections within range of population centers around New York.
Vibrio vulnificus can enter through unhealed cuts, scrapes, recent piercings, tattoos, and surgical incisions. The CDC advises washing cuts and scrapes thoroughly with soap and clean running water after contact with coastal waters or raw seafood.
The Associated Press contributed reporting.
