Flesh-eating bacteria sounds like the premise of a bad horror movie, but it’s a growing – and potentially fatal – threat to people.
In September 2023, the Centers for Disease Control and Prevention issued a health advisory alerting doctors and public health officials of an increase in flesh-eating bacteria cases that can cause serious wound infections.
I’m a professor at the Indiana University School of Medicine, where my laboratory studies microbiology and infectious disease. Here’s why the CDC is so concerned about this deadly infection – and ways to avoid contracting it.
What does ‘flesh-eating’ mean?
There are several types of bacteria that can infect open wounds and cause a rare condition called necrotizing fasciitis. These bacteria do not merely damage the surface of the skin – they release toxins that destroy the underlying tissue, including muscles, nerves and blood vessels. Once the bacteria reach the bloodstream, they gain ready access to additional tissues and organ systems. If left untreated, necrotizing fasciitis can be fatal, sometimes within 48 hours.
The bacterial species group A Streptococcus, or group A strep, is the most common culprit behind necrotizing fasciitis. But the CDC’s latest warning points to an additional suspect, a type of bacteria called Vibrio vulnificus. There are only 150 to 200 cases of Vibrio vulnificus in the U.S. each year, but the mortality rate is high, with 1 in 5 people succumbing to the infection.
Climate change may be driving the rise in flesh-eating bacteria infections in the U.S.
How do you catch flesh-eating bacteria?
Vibrio vulnificus primarily lives in warm seawater but can also be found in brackish water – areas where the ocean mixes with freshwater. Most infections in the U.S. occur in the warmer months, between May and October. People who swim, fish or wade in these bodies of water can contract the bacteria through an open wound or sore.
Vibrio vulnificus can also get into seafood harvested from these waters, especially shellfish like oysters. Eating such foods raw or undercooked can lead to food poisoning, and handling them while having an open wound can provide an entry point for the bacteria to cause necrotizing fasciitis. In the U.S., Vibrio vulnificus is a leading cause of seafood-associated fatality.
Why are flesh-eating bacteria infections rising?
Vibrio vulnificus is found in warm coastal waters around the world. In the U.S., this includes southern Gulf Coast states. But rising ocean temperatures due to global warming are creating new habitats for this type of bacteria, which can now be found along the East Coast as far north as New York and Connecticut. A recent study noted that Vibrio vulnificus wound infections increased eightfold between 1988 and 2018 in the eastern U.S.
Climate change is also fueling stronger hurricanes and storm surges, which have been associated with…
