Lana Kuykendall, 36, was in critical but stable condition at Greenville Memorial Hospital, hospital spokeswoman Sandy Dees said.

Kuykendall, who gave birth to twins this month at a Georgia hospital, came home to South Carolina and had severe pain in her leg, her husband, Darren Kuykendall, told a local television station. Within 15 minutes of noticing that the painful spot on her leg was spreading, she went to the hospital, he said.

She underwent her fifth surgery to remove necrotic, or dead, tissue from her lower leg after being hospitalized last Friday, the hospital said in a statement.

"A team of surgeons, critical-care physicians and infection disease specialists at Greenville Memorial Hospital continue to very closely monitor and treat her condition," the statement said.

Kuykendall was diagnosed with necrotizing fasciitis, a flesh-eating infection that can destroy muscles, skin and tissue.

Necrotizing fasciitis is typically managed by surgery, antibiotics and aggressive supportive care, the hospital said. "She remains very ill but stable," said Dr. Bill Kelly, hospital epidemiologist for Greenville Hospital System.

Lana Kuykendall is a paramedic. Her husband, Darren, is a firefighter.

"We're extremely grateful for the extraordinary medical care and the incredible community support we've received," Darren Kuykendall said.

THE WORST KIND

Dr. Jerry Gibson, an epidemiologist with the South Carolina Department of Health and Environmental Control said she was on a ventilator.

"She has the worst kind of bacterial infection," Gibson told Reuters. "It destroys tissues and invades the long membranes. We see four or five cases a year in South Carolina. There's no prevention."

Two other cases of flesh-eating infections have been reported recently in South Carolina and Georgia. But Gibson said, "These cases don't cluster together except randomly."

Different bacteria can cause necrotizing fasciitis. Gibson said he had not seen Kuykendall's medical chart and did not know what type of bacteria was to blame. The hospital would not name the underlying bacteria.

Necrotizing fasciitis can be caused by group-A streptococci or by staphylococci, common bacteria that live on people's skin and in their noses, he said.

"Normally, they do nothing," Gibson said. "Sometimes the group-A strep causes strep throat. Sometimes the staph causes a skin infection. Rarely, people can become infected in a place that's usually sterile - heart, lung, tissue under the skin - and have group-A strep where it shouldn't be.

HIGH MORTALITY RATE

"This is a condition that scares people," he said. "Patients are usually very normal and then they deteriorate fast. It usually starts at the site of a break in the skin. People may wash it out and it suddenly starts progressing."

Gibson said he does not know if Kuykendall's infection could have started in the hospital where she gave birth.

"It started growing on her leg," he said.

Necrotizing fasciitis has a high mortality rate. "It moves so fast and often requires very invasive surgery to correct it," he said.

In another recent case, Georgia college student Aimee Copeland, 24, was being treated for necrotizing fasciitis at Doctors Hospital in Augusta, Georgia. She has had most of one leg amputated and was expected to suffer the loss of her fingers as well.

Copeland contracted the infection after a zip-line accident in which she fell and cut her leg along the Little Tallapoosa River near Carrollton, Georgia. Doctors blamed her infection on the Aeromonas hydrophila bacteria, which are found in fresh or brackish water.

A former South Carolina fire chief, Glenn Pace, told a local television station he had been battling the disease since early April, spent 20 days in the hospital and had three surgeries on his foot but did not have to have his leg amputated.

The infection is caused by "something subtle, sometimes in a person who has poor nutrition or alcohol use but also in people who have no immune deficiencies," Gibson said.

The "flesh-eating" infection is not communicable, he said.

(Editing by David Adams and Xavier Briand)

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