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Flesh-Eating Bacteria May be Lurking in Giant Seaweed Mass Washing Up in Florida

According to researchers, clumps of the massive seaweed bloom – believed to be the largest in history – may harbor a deadly flesh-eating bacteria.

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FORT, PIERCE, FLORIDA — As the 5,000-mile wide blob of seaweed creeps across the Atlantic, scientists are now warning that clumps of the marine algae mixed with refuse could harbor flesh-eating bacteria.

The discovery by marine biologists at Florida Atlantic University (FAU) reveals that a dangerous bacteria known as Vibrio lurks in the vegetation decomposing along the state’s shoreline.


Local municipalities have already struggled with the pungent aroma of rotten eggs along Florida’s busy beaches. But now scientists advise locals and tourists to be careful around the brown sargassum washing up on shore.

Even more worrying, researchers say, is that ocean pollution contributes to the proliferation of the bacteria, which can cause disease and death if a person gets infected. Samples tested from the seaweed within the Atlantic belt were full of plastic debris, which interacts with the bacteria and algae to create a “perfect pathogen storm [with] implications for both marine life and public health”.

“Our lab work showed that these Vibrio are extremely aggressive and can seek out and stick to plastic within minutes,” Tracy Mincer, assistant professor of biology at FAU’s Harbor Branch Oceanographic Institute, said.

Mincer says the seaweed belt – double the width of the U.S. – is the perfect breeding ground for “omnivorous” strains of the bacteria that target both plant and animal life. The “microbial flora” can harbor potent levels of pathogens that are toxic to humans.


“We really want to make the public aware of these associated risks. In particular, caution should be exercised regarding the harvest and processing of sargassum biomass until the risks are explored more thoroughly,” Mincer said.

Reports of the news are causing worry among municipal cleanup crews and volunteers who work to clear the washed-up seaweed from beaches to make them more attractive

“It’s very alarming in the first place to see it on the beaches, and alarming to see all the plastic that is entangled in it. And now even more than that, there’s harmful bacteria too. That’s so scary,” Sophie Ringel, founder of the non-profit Clean Miami Beach told reporters on Wednesday.

The group is planning a beach cleanup this weekend to coincide with next week’s World Ocean Day and Ringer said recruits will take precautions with grabbers, thick gloves and sanitizer to avoid direct contact with the seaweed as much as possible.

“We’ll be paying extra attention and making sure everybody washes their hands, and doesn’t touch their faces after the cleanup. But I wonder what happens if we ingest it or come in contact with it?” Ringel wondered.


Florida’s Department of Health advises residents and visitors to avoid handling sargassum. The agency warns that Vibrio vulnificus infections “can be severe for people who have weakened immune systems, such as those with chronic liver disease.”

Florida’s Fish and Wildlife Commission is working with the Department of Environmental Protection (DEP) to monitor the incoming seaweed belt, reminding local municipalities that Florida’s legislature budgeted $5 million to assist with cleanup efforts.

“This is not a new phenomenon and many local governments, particularly in south Florida, are experienced in managing it on their beaches and already have management plans and the necessary authorizations in place to respond,” DEP spokesperson Jon Moore told reporters.

“We’re aware of the report, and our beach maintenance crews are instructed to wear gloves if they’re removing anything from the water’s edge and the sargassum related to plastics, or any other type of debris, pieces of wood or anything like that,” Moore said.

On a positive note, scientists at the University of South Florida (USF), who use satellite imaging to track the sargassum, say the amount in the Atlantic unexpectedly decreased by about 15 percent in May and is forecast to drop even more in the Gulf of Mexico this month.