Flesh-Eating Bacteria Thrive on Seaweed and Plastic

Plastic pollution and seaweed blooms in the Caribbean Ocean are providing the perfect breeding ground for flesh-eating bacteria, according to a recent study from Florida Atlantic University. The Vibrio bacteria typically feed on marine plant and animal tissues on coastlines, but researchers found them thriving on waste samples in the open ocean. This discovery is troubling because consuming seafood or seawater infected with these pathogens can cause life-threatening illnesses like cholera. Vibrio vulnificus, in particular, can even infect wounds and destroy surrounding tissue.

The team discovered multiple species of Vibrio bacteria, some of which have never been seen before, on plastic and seaweed samples. Further analysis suggested that some had "significant pathogenic potential." In experiments, the open-ocean bacteria quickly clung to and colonized plastic samples. This discovery is alarming, especially since Vibrio bacteria might be adapting to life on the open ocean in ways that could be dangerous to animal and human health. Some of the pathogens out in the blue might even be evolving toxic secretions, which can penetrate an animal's intestine to cause leaky gut syndrome.

Tracy Mincer, a marine biologist from Florida Atlantic University, explains that if a fish eats a piece of plastic and gets infected by this Vibrio, which then results in a leaky gut and diarrhea, it could release nutrients that stimulate Sargassum growth and other surrounding organisms. The widespread use of fertilizers has caused Sargassum seaweed in the Caribbean to bloom in greater swathes than ever before, suffocating stretches of beach in the process. As a solution, some experts think we should convert the abundance to food or biofuel.

Until the risks are explored further, researchers warn that we should hold off on harvesting the world's largest bloom of seaweed, as some have suggested. As floating seaweed and plastic debris mix and meet in the ocean like never before, they could tangle up and trade microbes, leading to potentially dangerous health outcomes when they wash up on the beach. Vibrio pathogens are still not fully accounted for, making it even more crucial to be aware of the associated risks of consuming contaminated seafood or swimming in infected waters. The study was published in Water Research, and researchers want to make the public aware of these risks so that they can take necessary precautions.