It was just another day for fisherman George Billiris when he took his grandson out in the water for the day.

Billiris owns the St. Nicholas Boat Line, a family run sponge diving operation in historic Tarpon Springs. So he's no newcomer to the Gulf of Mexico and the dangers of the open water. But he never thought he'd be one to develop a potentially life-threatening infection from flesh-eating bacteria.

Billiris, 63, said he and his grandson were standing in knee-deep gulf waters while fishing near the Anclote power plant along the Pinellas and Pasco county line on July 22. A canal feeds into the gulf in that area, making the water more brackish than the open sea.

"I had a couple of scabs on my leg but didn't think about it," he said.

Within 24 hours after the fishing trip, Billiris said he started to feel an intense burning sensation on his calf. Not long after that he developed a fever and chills. So he went to Mease Countryside Hospital, where he was diagnosed with a vibrio vulnificus infection.

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Vibrio Vulnificus is a bacteria that 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.

It's also one of two types of bacteria that leads to necrotizing fasciitis, which stops blood circulation, prompting tissue to die and skin to decay.

Group A streptococcus is the other kind of bacteria that causes it. It's the same bacteria that causes strep throat, and is generally considered the most common cause of necrotizing fasciitis, according to the U.S. Centers for Disease Control and Prevention. It's not found in water.

Necrotizing Fasciitis is somewhat rare, but it's called "flesh-eating" because the infection progresses so rapidly, 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.

"I wasn't sure what it was," Billiris said of his infection. "It's not something you ever think about until you get it."

Doctors immediately put him on a strong course of antibiotics. He developed a large blister on his calf, which became swollen and discolored. More than a week later, Billiris is still in the hospital, but he's starting to feel better.

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.

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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.

"I didn't realize how quickly it can become really serious," he said. "I was lucky when I came to the hospital when I did."

Billiris is the latest of several cases of flesh-eating bacteria in Florida so far this year.

A 77-year-old Ellenton woman scraped her leg in the waters off Anna Maria Island, got the infection and died. An Ohio man spent 11 days in the hospital and nearly lost a foot after being infected near Weedon Island. Another man hooked his hand and caught the infection while fishing in the gulf off the Pinellas County coast around Easter.

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. The easiest way to avoid it is to wash your hands regularly.

"I think I'm fortunate that I caught it in time," Billiris said. "I grew up on the water here and this is just a reminder to take precautions. I don't think most people are aware."

Contact Justine Griffin at jgriffin@tampabay.com or (727) 893-8467. Follow @SunBizGriffin.