A bacterial infection that can cause “flesh-eating” disease is becoming a bigger problem in the U.S.—and climate change is at least partly to blame.

Several states along the Gulf Coast and Eastern Seaboard have already reported a higher than usual tally of Vibrio vulnificus cases and deaths this summer. Last week, for instance, the Louisiana Department of Health issued a warning to residents over increased reports of V. vulnificus. Experts argue that milder winters and hotter summers are allowing these bacteria to thrive more easily than before in warmer waters.

“Every water sample we collect along the coast now contains some kind of Vibrio. That wasn’t true two decades ago,” Rachel Noble, a microbiologist at the University of North Carolina-Chapel Hill’s Institute of Marine Sciences, told local outlet WRAL Monday. North Carolina has seen 59 reported cases of V. vulnificus and one death as of July 31, according to health department data cited by WRAL—the second highest midsummer toll seen in 5 years.

V. vulnificus is a relative of the bacteria that cause cholera in people. It’s found in warm seawater or brackish water and usually enters the body through open cuts or by consuming raw shellfish. Wound infections can trigger a life-threatening condition called necrotizing fasciitis, which quickly kills off skin and tissue surrounding the wound (though this decay resembles eaten flesh, the bacteria themselves aren’t feeding off our skin).

Only around 150 to 200 cases of V. vulnificus are reported annually to the Centers for Disease Control and Prevention, but it can kill one of every five people who catch it, sometimes within days. And there’s growing evidence its presence in the U.S. is growing and expanding in range over time. A 2023 study found that reported cases in the eastern United States increased eightfold from 1988 to 2018, for example. Extreme weather events like heat waves and hurricanes can also drive spikes of the infection. Florida experienced a record high of 82 cases last year, with many arriving in the aftermath of Hurricane Helene.

Florida has only seen 13 V. vulnificus cases and four deaths so far in 2025, not far from its usual trends. Other areas have seen an uptick, however. 17 cases have occurred in Louisiana so far, for instance, with all victims hospitalized and four dead as a result—well above the typical toll. Over the preceding decade, the state had seen an average of seven cases and one death a year from V. vulnificus. 

These “flesh-eating” infections will remain a rare occurrence for the foreseeable future, but factors like climate change and extreme weather events have and will make them more common. So we should be more careful in the waters that carry these bacteria. Health organizations recommend that you avoid salt or brackish water if you’re sporting an open cut, for example, or at least that you wear a waterproof bandage before getting into the water. You should also thoroughly wash any cuts exposed to these waters or raw seafood. And you should seek immediate medical care if you develop a worsening skin infection around your cuts after these exposures, since necrotizing fasciitis can rapidly progress and turn lethal if untreated.