A grandmother is dead after contracting necrotizing fasciitis, commonly known as flash-eating disease, on a Florida beach.

On a Friday early last month, 77-year old Carolyn Fleming fell down while walking on the beach at her retirement community on Anna Maria Island, south of Tampa, and didn't think much of a small cut she got on her leg.  The next day, she was in terrible pain; a day after that, her leg was red and swollen and her friends forced her to go to an urgent care facility.  The doctor gave her a tetanus shot and an antibiotic, but a day after that her leg was turning black.

She was admitted to hospital, where doctors tried surgeries to try and save her leg, but the infection was insidious.

"On top of this she has suffered from two strokes and has suffered from kidney failure," her daughter-in-law Traci Fleming wrote on social media a week later.  "Her entire body is septic."

Doctors called in hospice care, and she died on 27 June.

"It is very ironic that she loved the beach so much and could not wait to retire there," Traci Fleming later wrote.  "But it's also what took her life away."

Ms. Fleming was the second person diagnosed with flesh-eating disease in Florida during June:  A 12-year old girl vacationing on the gulf coast with her family was left with a severely disfigured leg and will require therapy to learn to walk again.

A number of different bacteria that thrive in warm water - the most common being Group-A Strep and Vibrio - cause necrotizing fasciitis by getting under the skin and attacking the flesh.  People susceptible to infection are usually those with an open wound as well as people with an underlying medical condition.  The US Centers for Disease Control (CDC) recommends those with open wounds and active infections "to avoid bodies of water, especially swimming pools and hot tubs".