1. Health

Why is flesh-eating bacteria on the rise? Some point to climate change.

Cases of necrotizing fasciitis, commonly known as flesh-eating bacteria, are rising slightly, with a few recent cases reported in the Tampa Bay area. Some attribute the trend to rising water temperatures in the Gulf of Mexico, brought on by climate change. [Times (2014)]
Published Jul. 25

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If it seems like you're seeing more reports about flesh-eating bacteria, you actually are. The number of cases is up, though only slightly. And scientists have begun pointing to an increasingly familiar cause: climate change.

The trend will likely continue because of steadily warming temperatures in the Gulf of Mexico, which provide a "breeding ground" for the bacteria, said Dr. Sally Alrabaa, an an infectious disease specialist with USF Health and Tampa General Hospital.

"It's by no means an epidemic but we are seeing more cases this year," she said. "As the water is getting warmer by a few degrees the bacteria is flourishing for longer periods."

Necrotizing fasciitis, the infection's formal name, isn't caused by the same bacteria found in the blue-green algae or red tide blooms that Florida has seen recently. "But the two are closely related," Alrabaa said. "The bacteria that affects us has had a lot of food to 'eat' thanks to red tide, which has killed fish and marine animals. That's a lot of organic material for it to feast on."

Explaining it doesn't make the situation any less concerning. Several recent reports from Tampa Bay and other parts of Florida have rattled a population that regularly comes into contact with the water. Among the cases: A 77-year-old Ellenton woman who scraped her leg in the waters off Anna Maria Island, got the infection and died; an Ohio man who spent 11 days in the hospital and nearly lost a foot after being infected near Weedon Island; another man who hooked his hand and caught the infection while fishing in the gulf off the Pinellas County coast around Easter.

Necrotizing fasciitis is caused by bacteria that stops blood circulation, prompting tissue to die and skin to decay. It is somewhat rare, but it's called "flesh-eating" because the infection is so rapidly progressing, doctors say. Even with treatment, one in three patients die from necrotizing fasciitis, according to the U.S. Centers for Disease Control and Prevention. Since 2010, the agency says, between 700 and 1,200 people a year have contracted the infection in the United States. But cases have gone up in the last year in Florida.

RELATED: Flesh-eating bacteria in Florida waters: Three things you need to know.

Most healthy adults will be able to fight off a necrotizing fasciitis infection without hospital care.

It's the elderly, children and people with compromised immune systems or issues like liver disease who are more susceptible to the infection. The easiest way to avoid it is to wash your hands regularly.

There are two known strains of bacteria that cause necrotizing fasciitis: Group A Streptococcus and Vibrio Vulnificus. Group A Streptococcus is the same bacteria that causes strep throat, and is generally considered the most common cause of necrotizing fasciitis, according to the CDC. It's not found in water.

Vibrio Vulnificus, on the other hand, lives and breeds in warm and brackish water, and can infect someone by entering the body through a cut or scrape. People can also contract it by eating raw seafood, like oysters or sushi, infected with the bacteria.

"The gulf is its natural habitat," said Valarie Harwood, professor of water quality microbiology and microbial ecology at the University of South Florida. "In Tampa Bay, swimmers are exposed to hundreds of thousands of micro organisms. When the water temperature is over 75 degrees, we'll see more of them. The warmer it is, like 85 to 90 degrees, the better it is for bacteria. They're loving it."

That's why summer tends to be when the most flesh-eating bacteria cases are reported, she said.

"There's more Vibrio Vulnificus bacteria in brackish water, like an estuary, than the open Gulf of Mexico," Harwood said. " They tend to like areas where there is less salt in the water."

But it's the warmer temperatures that bring Vibrio Vulnificus out in greater numbers.

A study published last month in the Annals Of Internal Medicine examined a rise in the number of Vibrio Vulnificus cases reported in Delaware Bay over a 10-year period. From 2008 to 2016, researchers found there was just one reported case in the region, where in general, the water is too cold to support the bacteria. But there were five cases reported in just one year, from 2017 to 2018. Researchers linked the rise to warming waters from climate change.

"It's there no matter what," Harwood said of the bacteria in Florida. "So people should use common sense before getting in the water, especially if they have a cut or an abrasion, or are immune-compromised."

PREVIOUS COVERAGE: Two cases of 'flesh-eating' bacteria revive concerns among Tampa Bay area doctors

Once infected, swelling usually occurs right away and blisters can form over the wound site. Those blisters will turn black and blue over time as tissue and skin begins to die. Those who have the infection will feel flu-like symptoms of fever, dizziness and cold sweats right away. Severe complications are common, like sepsis, shock and organ failure.

Recovering from necrotizing fasciitis depends on how fast the infection is caught and treated by medical professionals. Multiple surgeries are fairly common to remove infected tissue, as are long courses of potent antibiotics.

"People are dying from global warming, it's just not in ways they often expect," Alrabaa said. "It's not dramatic, but it's happening. As the water continues to warm over time, we're going to see more infections like these."

This story was produced in partnership with the Florida Climate Reporting Network, a multi-newsroom initiative founded by the Miami Herald, the Sun-Sentinel, The Palm Beach Post, the Orlando Sentinel, WLRN Public Media and the Tampa Bay Times. Contact Justine Griffin at or (727) 893-8467. Follow @SunBizGriffin.


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