'Flesh-Eating Bacteria' FAQ

By Kathleen Doheny
WebMD Health News

Reviewed by Arefa Cassoobhoy, MD, MPH

Aug. 1, 2014 -- Summer is prime season for a bacteria called Vibrio vulnificus -- also known as "flesh-eating" bacteria -- to thrive, especially in warm Gulf Coast waters. Swimmers and those who eat seafood should be careful to avoid infection from this potentially fatal bacteria.

Earlier this summer, Florida health officials issued a reminder that the bacteria thrives not just in Florida but in other coastal states surrounded by warm saltwater.

While infection with the bacteria is a rare cause of disease, taking simple precautions can minimize the risk and decrease the chances of the bacteria becoming ''flesh-eating." That's especially true when the bacteria is thriving -- from May through October .

WebMD turned to public health experts to shed more light on these bacteria and to get advice on how to stay healthy.

Where is Vibrio vulnificus found?

The bacteria thrive in warm saltwater. Most cases of infection happen in the Gulf Coast region, including Alabama, Florida, Louisiana, Mississippi, and Texas, the CDC says.

"The bacteria thrive in warm water, so concentrations of the bacteria are higher during the summer months," says Carina Blackmore, PhD, Florida's acting state epidemiologist.

How do you get it?

Eating uncooked seafood can bring on the infection. Also, if a skin injury is exposed to the bacteria, the wound can become infected.

The bacteria can also infect the blood, especially if someone has chronic liver disease or other medical problems that compromise their immune system. This type of infection can become severe and even fatal. Bloodstream infections with V. vulnificus are lethal in half of those affected, the CDC says.

There is no evidence the bacteria is transmitted from person to person, the CDC says.

How common is it?

In the U.S., about 95 cases occur each year, according to the CDC, although only half of those are confirmed by culturing the blood, the stool, or a wound. Of those, about 85 patients need to be in the hospital; about 35 die.

In Florida, 11 cases have been reported in 2014, says Sheri Hutchinson, a spokeswoman with the Florida Department of Health, with two deaths as of July 25. In 2013, 41 cases were reported, with 11 deaths.

Who is most at risk, and how can people minimize the risk?

Those who eat raw seafood and those who have open wounds and go into warm saltwater risk infection are at risk.

"People with underlying health problems and people who are immune-compromised, especially those with chronic liver disease, are at higher risk," Blackmore says.

Don't go into the water if you have broken skin or open wounds.

Don't eat raw shellfish, especially oysters. Refrigerate leftover fish promptly.

What are typical symptoms?

Someone who eats seafood infected with the bacteria may have vomiting, diarrhea, and abdominal pain.

An infected wound can become ulcerated -- redden, ooze pus, streak with red lines, or grow in size -- and the skin can break down.

Someone with a compromised immune system may experience fever, chills, very low blood pressure associated with shock, and blistering skin lesions.

Seek medical help right away if you notice these symptoms, Blackmore says.

It's been called a ''flesh-eating'' bacteria -- is that true?

"In vulnerable patients with wound infections, the bacteria can create severe tissue damage and skin breakdown -- necrotizing fasciitis -- at the wound site," Blackmore says. While this is often referred to as ''flesh-eating bacteria," Blackmore says, medical experts consider it a misnomer. ''The bacteria don't actually consume the flesh. The bacteria have toxins that are destroying the cells in the tissue. The cells end up dying from the toxin exposure."

How is it diagnosed, and what is the treatment?

Besides observing symptoms, doctors can test the blood, the wound, or the stool to confirm the diagnosis.

Patients receive antibiotics. The length of treatment and the dose vary by the type of antibiotic used. Some regimens are up to 14 days.

The infected wound is treated, and surgeons may be needed to clean the wound and remove dead tissue. Nurses may apply special bandages to care for the wound.

"Healthy people typically fully recover from an infection," Blackmore says. "Persons with milder infections can recover within a few days. People with underlying illnesses who have more severe forms of the disease have a more extended recovery period."

SOURCES: CDC: "Vibrio vulnificus." Tajiri, T. Pathology International, March 2008. Carina Blackmore, DVM, PhD, chief, Florida Bureau of Environmental Public Health Medicine; Florida acting state epidemiologist. Sheri Hutchinson, Florida Department of Health.

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