It can require oxygen therapy or the help of ventilator for treatment, according to the NIH.

CNN: STORY HIGHLIGHTS

In the emergency department she was found to have influenza and was admitted for IV fluids and oxygen therapy.

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You may need up to three treatments on the first day of hyperbaric oxygen therapy, followed by twice-daily treatments for up to five days.

CNN: Gangrene

Hyperbaric oxygen therapy for gas gangrene generally lasts about 90 minutes.

CNN: Gangrene

Hyperbaric oxygen therapy may be used to treat gas gangrene.

CNN: Gangrene

Biomet is a leading maker of orthopedic devices for joint replacement and Lincare is the number two provider of oxygen and respiratory therapy for patients at home.

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The only therapy is giving oxygen, which delivers some benefits but cannot prevent eventual deterioration and death from the illness.

BBC: Lung research hints at fresh therapy